3 EWSD System Descr

s

EWSD – for the New Network Generation Technical System Description

2

The Proven Platform forTelecommunications Requirements . 4

The Complete Range of Telecommunications Services from a Single Source . . . . . . . . . . . 10

ADSS – Advanced SubscriberServices . . . . . . . . . . . . . . . . . . . . . . 12

ISDN – Integrated Services Digital Network . . . . . . . . . . . . . . . . 22

GeoCENTREX – Central Office Exchange Service . . . 32

EWSD InterNode – Internet Supplementary Services . . 48

IN – IN Services in the Network Node . . . . . . . . . . . . . . . . 52

ADMOSS – Advanced Multifunctional Operator Service System . . . . . . . . 56

Basic Functions Ensure EfficientOperation . . . . . . . . . . . . . . . . . . . . 61

Additional Functions Expand the Range of Applications . . . . . . . . 72

EWSCountry – Cost-Efficient CallProcessing for Rural Areas . . . . . . . 75

EWSD Hardware – Powerful, Versatile and Flexible . . . 77

EWSD Software – Intelligence for Every Application . . 82

EWSD Operation and Maintenance – Efficiency at an Optimized Cost . . . 86

Structural Layout . . . . . . . . . . . . . . . 94

From Planning to Operation . . . . . . 98

Documentation to Meet all Needs . . . . . . . . . . . . . . . . . . . . .103

Quality for the Entire Life Cycle . . . 105

Technical Data . . . . . . . . . . . . . . . . 106

Abbreviations . . . . . . . . . . . . . . . . . 112

3

Switchingthe Future.

EWSDInnovations

Siemens was quick to realize thedirection in which telecommunica-tions was developing.The digital elec-tronic switching system EWSD wastherefore given a major innovativeoverhaul and is now in a position tosolve the telecommunications prob-lems of tomorrow.

For network operators, EWSD repre-sents the latest in communicationtechnology, providing a fast and cost-efficient response to all the challengesfacing the telecommunications mar-kets.

EWSD implements all telecommuni-cations applications on a proven hard-ware platform.This platform is a highlyeconomical and reliable one and rep-resents a sure investment for the future.

Network operators who choose EWSDchoose continuity. EWSD is alreadythe best-selling product of its typeand is being used successfully in over100 countries throughout the world.By the start of 1998, over 150 millionaccess lines had been installed, whichmeans that one in every five calls inthe world is processed with EWSDtechnology.

EWSD is the solution for telecommunicationsrequirements in the 21st century.

As we stand on the threshold of the 21st century,major challenges are facing the world of telecommunications:

Competition is growing within the market

Subscriber traffic volume is increasing

The range of new services is expanding

Speech and data networks are growing together

Internet usage is increasing rapidly

Multimedia services present new opportunities

4

EWSDThe Proven Platform forTelecommunications Requirements

Network operators throughout theworld are preparing for the chal-lenges about to face telecommuni-cations networks in the nextcentury.

All the prerequisites for meetingthese challenges are already avail-able from EWSD, which providesthe necessary functions on a com-mon platform.

• EWSD PowerNode – for a more powerful anddynamic network

From the very beginning, EWSDwas developed as an open systemwith a flexible hardware and softwarearchitecture. The EWSD PowerNode is the logical continuation ofthis trend. It incorporates the pow-erful new EWSD hardware platform,on which both the new and theclassical switching applications canrun simultaneously. There are un-limited possibilities for future appli-cations. The EWSD PowerNodeoffers a flexible, economic solutionfor all requirements resulting fromdifferent network structures andsizes.

The new applications imple-mented on the EWSD platform are:

• EWSD InterNode – to optimize Internet access

• EWSD BroadbandNode – the bridge to the world of multimedia services

The classical applications canalso be used on the EWSD platform:

• Local network node

• Transit network node

• Network interworking node infixed networks

• Mobile communication networknode in mobile networks

• Service Switching Point (SSP) inintelligent networks (IN)

• Signaling Transfer Point (STP)

5

EWSD PowerNode

The EWSD PowerNode is the an-swer to the changes currently under-way in network structure. With theEWSD PowerNode, the networkcan now attain the high power levelit requires to deal with the rapidincrease in subscriber traffic in con-junction with new services.

The change in network structure,i.e. network consolidation, is a resultof the costs situation facing networkoperators. As networks becomederegulated, competition is growingamong the various telecommunica-tions networks, and prices for ex-isting services are falling all thetime. Network operators are nowtrying to offset the effects of thelower prices by reducing their oper-ating costs.

On the one hand, network consoli-dation means decreasing the numberof network nodes and dismantlingnetwork hierarchies; however, italso results in control functionsbeing centralized among a smallnumber of network nodes. Existinganalog network nodes or thesmaller digital network nodes arebeing replaced by remote lineunits.Those network nodes that re-main have to be powerful enoughto take on the control of the sub-scribers at the remote line units.

The growing need for powerful net-works is also due to an increase insubscriber traffic, which primarilyresults from the new communica-tions services with transmissionrates of up to 2 Mbit/s.These com-munications services include theintegrated services digital network(ISDN), online services and theInternet, as well as services withn x 64 kbit/s.

The EWSD PowerNode has thecapacity to cope with major net-work consolidation. It covers all net-work-node applications, such asthose for local network nodes, transitnetwork nodes and network inter-working nodes.

The EWSD PowerNode can also beused as a mobile services switchingcenter (MSC) in mobile networks oras a service switching point (SSP)in intelligent networks (IN). In addi-tion, the PowerNode hardware canform a cost-efficient basis for a stand-alone signaling transfer point (STP).

While the individual system com-ponents are now much more pow-erful, the EWSD PowerNode isstill based on the tried and testedhardware and software structure ofEWSD. This means that existingEWSD network nodes can be easilyupgraded to incorporate the morepowerful components. ExistingEWSD periphery can still be usedwith the EWSD PowerNode, soany investment in EWSD peripheryretains its value.

One important element of theEWSD PowerNode is the remoteswitching unit (RSU), which coversthe needs of the large remote lineunits.

6

EWSD InterNode

The EWSD InterNode integratesInternet technology into the EWSDsystem: it creates the basic condi-tions required for speech and datanetworks to grow together.

Network operators have the corecompetency to amalgamate theircurrent communications processeswith the Internet world. Also, withtheir existing network, they alreadyhave the ideal infrastructure for link-ing up to the Internet.

Through the Internet, network opera-tors can themselves take on the roleof Internet service provider, as wellas opening up a completely newsource of income by providing highbit-rate connections over the regularsubscriber line.

The number of Internet users ismultiplying throughout the worldevery year, with a corresponding in-crease in Internet traffic. New ap-plications such as the World WideWeb (WWW), Voice over Internetand e-mail are also contributing tothe growth in traffic.

In the network structure of the fu-ture, the EWSD InterNode linksthe telephone network to the Inter-net. The interface between sub-scribers and the Internet is formedby the point of presence (PoP),which is integrated in the EWSDInterNode. A common platformshared by the EWSD InterNodeand EWSD PowerNode ensurescommon management, billing andoptimum interworking of Internetusers and telephone subscribers.The EWSD InterNode thus meanslow startup investment for Internetaccess as well as optimized operat-ing costs.

The EWSD InterNode offers unre-stricted access to Internet services.In addition, the EWSD InterNodeprovides value-added services thatare only possible through a combi-nation of the Internet and tele-phony.

Each subscriber with access to theInternet via the EWSD InterNoderemains fully accessible by tele-phone during the Internet session.Meanwhile, the network operatorbenefits from a higher call rate andfrom additional call-charge income.

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EWSD BroadbandNode

The EWSD BroadbandNode isthe foundation stone for a future-oriented network in which varioustypes of technology, such as ISDNin the public network (PSTN) andbroadband communication, harmo-niously operate together throughthe asynchronous transfer mode(ATM).

Broadband technology offers thenetwork operator the opportunityto introduce completely new ser-vices, e.g. services with high-qualitygraphics and multimedia applica-tions as well as videotelephony. Inaddition, broadband technologycan meet subscribers’ demandsfor shorter response times for highbit-rate applications.

The EWSD BroadbandNode pro-vides ATM line technology andATM switching technology along-side narrow-band technology. As aresult, several system componentscan be used for both a narrow-band application as well as abroadband application. The EWSDBroadbandNode ensures optimuminteraction of narrow-band andbroadband technology.

A common hardware platform fornarrow-band and broadband tech-nology in the EWSD Broad-bandNode ensures commonmanagement, billing and optimuminterworking. The EWSD Broad-bandNode requires low startup in-vestment for broadband accesswhile also ensuring optimum oper-ating costs.

ATM subscribers and ATM trunksto other broadband networks canbe connected cost-efficiently bymeans of the EWSD Broad-bandNode. ATM lines are alsoavailable on the remote subscriberconcentrators (DLU) and the re-mote switching unit (RSU).

8

Local network nodes

Local network nodes are used forswitching the incoming and out-going traffic for the subscribersconnected. Up to 600,000 sub-scribers may be connected to anEWSD local network node.To this end, EWSD offers the com-plete range of subscriber inter-faces:

– analog lines

– ISDN basic accesses (ISDN-BA)

– ISDN primary rate accesses (ISDN-PA)

– V5.1 interface

– V5.2 interface

– high bit-rate lines universal asymmetrical digitalsubscriber line (UDSL),symmetrical digital subscriberline (SDSL)

– 2-Mbit/s high-speed lines

Subscribers are connected to theEWSD system by means of digitalline units (DLU). Depending on thenetwork situation, the DLUs canbe positioned locally in the EWSDnetwork nodes or as remote DLUsin proximity to the subscribers tobe connected.

Within EWSD, the remote switchingunit (RSU) assumes the function oflarge remote line units. The RSUcan be used in the consolidation oftraditional networks and also in thecreation of new networks in placeof small network nodes or DLUclusters. Up to 50,000 subscriberscan be connected to an RSU. Inter-nal traffic is switched through di-rectly in the RSU. This reduces theload on the transmission equip-ment to the controlling EWSD net-work nodes. As a result, thetransmission paths can be dimen-sioned in a cost-effective manner.

Transit network nodes

In the transit or long-distance net-work nodes, interregional traffic isswitched to and from other networknodes. Up to 240,000 incoming,outgoing or bothway trunks may beconnected to EWSD transit networknodes.

Signaling Transfer Point (STP)

Signaling transfer points transferreceived signaling messages inquasi-associated signaling trafficto another STP or a signaling endpoint, on the basis of a destinationaddress. No call processing is per-formed on the signaling messagesin a signaling transfer point.The en-tire signaling traffic is handledsolely via the message transferpart (MTP, levels 1, 2 and 3). Userparts (level 4) are not involved, orare not even present in the STP. Asignaling transfer point can be inte-grated in a network node or it canform a separate node in the signal-ing network. In the case of a stand-alone STP, only SS7 signalingchannels are connected. There areno subscriber lines or trunks.

As a safeguard, signaling transferpoints may be duplicated in an SS7network (so-called "mated pairs").This means that if one STP fails, thesecond STP can take over thewhole traffic load. A backbone con-figuration is implemented on ahigher SS7 network level as a gen-eral, network-wide safeguard. Onevariant of the stand-alone STP isthe signaling relay point (SRP). TheSRP also contains the SCCP globaltitle translation function (GTT).

Network interworking nodes

Network interworking nodes areused for switching internationaland intercontinental traffic. Theyalso form the point of connectionto networks of other national oper-ating companies and to mobile net-works. EWSD includes all thefunctions required for this, such asinternational signaling, echo com-pensation for intercontinental con-nections and satellite connectionsas well as interadministrativebilling.

Combined network nodes

The functions of local networknodes, transit network nodes andnetwork interworking nodes can becombined in a single EWSD net-work node. The number of sub-scriber lines and trunks to beconnected is determined by themaximum traffic capacity of theparticular network node. The maxi-mum possible overall traffic load is100,000 erlang.

Mobile communication networknodes

In the Siemens mobile communi-cation system, EWSD assumesthe functions of the switching sub-system (SSS). EWSD provides allthe mobile-specific functions thatare needed for operating a mobilecommunication network.

With the mobile services switchingcenter (MSC), EWSD operates as amobile communication networknode in controlling the trafficwithin the mobile communicationnetwork and the traffic to the fixednetwork and to other mobile com-munication networks. The data-base function of the visitor locationregister (VLR) is implemented inthe same network node.

9

network and to other mobile com-munication networks. The data-base function of the visitor locationregister (VLR) is implemented inthe same network node.

There are separate EWSD networknodes for the database functions ofthe home location register (HLR) /authentication center (AC) and theequipment identification register(EIR). As one of the world’s leadingsuppliers of telecommunicationstechnology, Siemens offers a com-plete mobile communication solu-tion under the name AirXpress.

With its product portfolio, Siemensoffers a complete IN solution underthe name INXpress.

As an alternative to the conven-tional IN solution on several levels,EWSD also permits a reducednumber of lucrative IN services onthe basis of compact solutions ona single level.

Service Switching Point (SSP)in the intelligent network (IN)

The term intelligent network (IN) isused throughout the world to rep-resent a network architecture inwhich services are controlled froma central location.

In the standardized architecture ofan IN, EWSD is implemented as aservice switching point (SSP). TheEWSD-SSP thereby provides theservice access function within theIN. EWSD network nodes at eachnetwork level can be easilyequipped with the SSP functions:all that is required is a softwareexpansion.

EWSD offers a complete range ofservices for all telecommunicationssectors and applications. Thismeans that a network operatorusing EWSD has a considerableadvantage over rival operating com-panies.

Each service is accompanied by awide range of features. By config-uring its network to meet a specificmarket demand, the network oper-ator can therefore stand out fromthe competition.

The EWSD feature spectrum wasdeveloped with market require-ments in mind. In the future, thefeature spectrum will continue toevolve in keeping with the growingneeds of subscribers and networkoperators. Feature recommendationsor standardizations from ETSI orITU-T are also taken into considera-tion in further developments.

ADSS

The term advanced subscriber ser-vices (ADSS) refers to the featurespectrum made available to analogsubscriber lines. Analog featuresfacilitate the act of telephoning, im-prove subscriber accessibility, in-crease the level of user-friendliness,and help subscribers to cut theircosts.

ISDN

The integrated services digital net-work (ISDN) offers a high-perfor-mance infrastructure for newtelecommunications applications.Every ISDN subscriber is providedwith two 64 kbit/s user channelsand one 16 kbit/s signaling channel.In addition to telephony, an ISDNline can also be used simultane-ously for data services such asimage transmission and data trans-mission. A wide range of featuresis available to ISDN subscribers.

10

EWSDThe Complete Range ofTelecommunications Services from aSingle Source

11

GeoCENTREX

GeoCENTREX is the EWSD productname for its central office exchangeservice. GeoCENTREX providesthe function of private branch ex-changes within EWSD. Using Geo-CENTREX, analog subscribers aswell ISDN subscribers and existingprivate branch exchanges can beintegrated throughout the networkin a virtual private branch exchange.

EWSD InterNode

EWSD offers not just the technicalprerequisites for easy Internetaccess, but also a range of exclusivefeatures that facilitate interactionbetween the Internet and tele-phony.

IN services in the network node

EWSD makes it possible to enterthe world of IN-based services in afast and cost-efficient manner onthe basis of just one network node.Each EWSD network node can beused to implement a wide range offeatures that would otherwise onlybe available with an extensive IN.The features can also be made avail-able to subscribers who are con-nected via network nodes of othermanufacturers.

ADMOSS

The advanced multifunctional oper-ator service system (ADMOSS) isan EWSD service for all applica-tions for which operator assistanceis required or is requested by thesubscriber. Modern call centersbased on ADMOSS form one of themost important links to the endcustomer.

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ADSSAdvanced Subscriber Services

The Advanced Subscriber Services(ADSS) provide EWSD with the en-tire spectrum of all analog features.Each network operator can nowadapt its range of features to meetthe specific needs of its customers.

Subscriber features forincoming calls

Using the Call Forwarding (CF)feature, a subscriber can forward in-coming call requests to any desireddestination.Calls can be forwarded either im-mediately (Call Forwarding Uncon-ditional, CFU), when there is noreply (Call Forwarding on no Reply,CFNR) or when the line is busy(Call Forwarding on Busy, CFB).When a subscriber has activatedcall forwarding, an announcementcan be used to inform calling par-ties that their call request is beingforwarded. For the individual callforwarding types CFU, CFNR, CFB,different call forwarding destina-tions can be reached independentlyof each other.

With the feature Call Forwardingto a Fixed Announcement (CFFA),a subscriber can forward incomingcalls requests to a specific an-nouncement. Calls can be forwardedeither immediately or after a prede-fined period of time. During thiswaiting time the forwarding sub-scriber can still accept the call.

With the feature Call Forwardingto a Group of Announcements(CFGA), a subscriber can forwardall incoming call requests to one of15 possible announcements. Callscan be forwarded either immedi-ately or after a predefined period oftime. During this waiting time theforwarding subscriber can still acceptthe call.

With the feature Call Forwardingto an Operator (CFO), a subscribercan forward all incoming call re-quests to an operator. Calls can beforwarded either immediately orafter a predefined period of time.During this waiting time the for-warding subscriber can still acceptthe call.

With the feature Call Forwardingto a Voice Mail Service (CFVMS),a subscriber can forward all incomingcall requests to a voice mail system.Here, the calling party can leave amessage. Calls can be forwardedeither immediately or after a prede-fined period of time. During thiswaiting time the forwarding sub-scriber can still accept the call.

With the feature Call Forward-ing Controlled by Operator(CFCO), it is the operator whocreates the destinations for asubscriber’s call forwarding.

EWSD

B29999

CF active

B14711

Ringing time

A

Subscriber 4711:

CFU .............................CFNR 9999CFB ............................

Call Forwarding Controlled by Operator (CFCO)

Operator

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A subscriber using the feature CallForwarding to a Voice Mail Service(CFVMS) can be notified of a newvoice mail message by means ofthe feature Message WaitingIndication (MWI).

The feature Multiple SimultaneousCall Forwarding (MSCF) supple-ments the Call Forwarding (CF)feature. Up to 10 incoming call re-quests can be forwarded simulta-neously to a specified destination(e.g. to a voice mail service).

The Call Waiting (CW) featuremakes it easier to reach a subscriber.This feature notifies a subscriber onan existing call that another party istrying to set up a connection to thisline.The subscriber can then decideto accept or ignore the waiting call.

In the Distinctive Call Waiting(DCW) feature, different call waitingtones enable the subscriber to dif-ferentiate between different typesof waiting calls.For instance, the subscriber canrecognize forwarded calls or differ-entiate between national and inter-national calls.

The Distinctive Ringing (DR) fea-ture enables the subscriber to differ-entiate between certain types ofconnections by means of differentringing sequences.For instance, the subscriber canrecognize forwarded calls or differ-entiate between national and inter-national calls.

If a subscriber does not wish to bedisturbed, the Do Not Disturb(DND) feature can be activated toforward incoming calls to a differentdestination, e.g. a general an-nouncement.

With the feature Multiple Sub-scriber Number (MSN), up to fourdifferent directory numbers can beassigned to one line. EWSD treatseach multiple subscriber number asan independent directory numberto which features can also be as-signed on an individual basis.Using the Different Ringing feature,calls to each individual directorynumber can be signaled with differ-ent ringing sequences.

The Call Waiting Deluxe (CWD)feature is an extension of CallWaiting (CW). This feature pro-vides the analog subscriber withmore possible ways of reactingto waiting calls. For example, thesubscriber can forward the call,set up a three-party conference,or hold either the incoming orthe existing call and switch be-tween the two.

AnalogEWSD

Possible reactions when CWD is active:

Incoming Call Existing Call

ignore hold

reject hold

accept terminate

accept put on hold

put on hold hold

set up a three-party conference

forward hold

CWD active

C

A B

Call Waiting Deluxe (CWD)

14

The feature Parallel Ringing (PRNG)simultaneously signals calls to twoseparate lines belonging to thesame subscriber, e.g. a fixed line inthe PSTN and a mobile number.Thesubscriber can accept the call oneither of the two lines.

With the feature Selective CallAcceptance (SCA), only those callrequests from certain defined direc-tory numbers are connected throughto the line. All other call requestsare rejected.The subscriber can de-fine up to 50 directory numbers. Itis also possible to specify partial di-rectory numbers.

Using the feature Selective CallForwarding (SCF), call requestsfrom defined directory numbers orwith specific prefixes can be for-warded to any destination. Similarly,call requests from defined directorynumbers or with specific prefixescan be excluded from call forwarding.The subscriber can define up to 50directory numbers. It is also possibleto specify partial directory numbers.

With the feature Selective CallRejection (SCR), call requestsfrom certain defined directory num-bers are rejected. The subscribercan define up to 50 directory num-bers. It is also possible to specifypartial directory numbers.

With the feature Selective CallWaiting (SCW), waiting call re-quests from defined directory num-bers are indicated to the calledsubscriber by means of differentcall waiting tones. The subscribercan define up to 50 directory num-bers. It is also possible to specifypartial directory numbers.

With the Selective Ringing (SR)feature, call requests from certaindefined directory numbers are sig-naled to the analog subscriber bymeans of different ringing se-quences.The subscriber can defineup to 50 directory numbers. It isalso possible to specify partial di-rectory numbers.

WIth the feature Series Comple-tion Service (SCS), a group of di-rectory numbers can be created fora subscriber (individual line or PBX).If the subscriber is called but isbusy, the call request is automati-cally forwarded sequentially to anavailable subscriber within the di-rectory number group.

Subscriber features foroutgoing calls

With the Abbreviated Dialing(ABBD) feature, a subscriber candraw up an individual abbreviateddialing list. The directory numberschosen are assigned an abbreviatednumber in the list. The connectioncan then be set up by simply dialingthe abbreviated number. During callsetup, EWSD automatically convertsthe abbreviated number into thefull directory number.

With the Automatic Recall (AR)feature, a called analog subscriberis able to initiate the last call thatcould not be set up originally (e.g.because the call was terminated bythe calling party).The subscriber ac-tivates recall by dialing the appro-priate feature code. EWSD thenautomatically sets up the recallconnection.

The feature Rejection of Forwar-ded Calls (RFC)) enables sub-scribers to automatically rejectcall requests forwarded to them.

EWSD

B1

CF active

RFC active

STOP

A

B2

Rejection of Forwarded Calls (RFC)

15

The feature Call Completion toBusy Subscriber (CCBS) enablesthe subscriber to ring back auto-matically. The calling subscriberactivates this feature when thecalled subscriber is busy. The net-work then indicates by means ofrecall as soon as the called partyhas become available. If the callingparty accepts this ringback call, theEWSD automatically sets up theconnection once again to the calledsubscriber.

The feature Call Completion on noReply (CCNR) also enables thecalling subscriber to ring back auto-matically.The calling subscriber acti-vates this feature when the calledparty does not reply. The networkthen indicates by means of recallas soon as the called party becomesactive again (e.g. when he/she isfree again after initiating a call).If the calling party accepts this ring-back call, EWSD automatically setsup the connection once again tothe called subscriber.

With the feature Fixed DestinationCall (FDC), also known as Hotline,a call can be made to a specificdestination without having to dial.Call setup can begin as soon as thehandset is lifted or after a prede-fined period of time.

With the feature Selective CallOriginating (SCO), call setup canbe suppressed to certain defineddirectory numbers (black list func-tionality) or, alternatively, calls areonly permitted to defined directorynumbers (white list functionality).The black list/white list functionalitycan be administrated for each indi-vidual subscriber.

An analog subscriber can use theSubaddressing (SUBA) feature,for example, to reach a specificterminal of an ISDN subscriber.

The Call Barring feature enablesthe subscriber to protect his or herline from unauthorized use. The op-erating company can specify up to32 traffic restriction classes, fromwhich the subscriber is free tochoose a suitable one. In addition, acode-dependent restriction is alsopossible for prevention of unautho-rized feature usage on a line.

Display features

With the feature Called LineIdentification Restriction (CALR),an analog subscriber who has acti-vated call forwarding can suppressdisplay of his or her directory numberat the forwarding destination.

With the feature Calling Line Iden-tification Presentation (CLIP), acalled subscriber can request displayof the calling party’s directorynumber.

With the feature AnonymousCall Rejection (ACR), a sub-scriber can automatically reject acall request if a calling sub-scriber suppresses display of hisor her directory number. In thiscase, the calling subscriberhears a special tone or an an-nouncement indicating incom-plete call setup.

If required, the subscriber usingAutomatic Recall can arrange forthe directory number of the sub-scriber who is being re-called tobe announced or displayed onan appropriate terminal.

EWSD

ACR activeCLIR active

announce-ment:

_ _ _ _

Anonymous Call Rejection (ACR)

The called partyneeds your directory number

A

B

16

With the feature Calling Line Iden-tification Restriction (CLIR), callingsubscribers can suppress display oftheir directory number for the calledsubscriber. Certain subscribergroups (e.g. police) can be assignedspecial permission authorizingthem to ignore such suppression.

With the feature Connected LineIdentification Restriction (COLR),a called subscriber can suppressdisplay of his or her directory numberfor the calling subscriber.

With the feature Calling NameIdentification Restriction(CNIR), a calling subscriber cansuppress display of his or hername for the called subscriber.Certain subscriber groups (e.g.police) can be assigned specialpermission authorizing them toignore such suppression.

With the feature Calling NameIdentification Presentation(CNIP), a called subscriber canhave the calling party’s namedisplayed. For this feature, thesubscribers’ names must havebeen stored in the networknode of the calling subscriber.

EWSD

CNIP active

B

CNIR

active

STOP

List of names:

Subscriber A: NAME

A_ _ _ _

Calling Name Identification Restriction (CNIR)

EWSD

Access CodeTest Data Message

T.D.M.

Test Data Message

EWSD

CNIP

active

List of names:

Subscriber A: NAME

ANAME

Calling Name Identification Presentation (CNIP)

B

17

The feature Calling Line Identifi-cation for Waiting Subscribers(CLICW) expands the possibilitiesof the Call Waiting (CW) feature.The subscriber receiving the waitingcall is shown the directory numberof the waiting subscriber as addi-tional information.

PBX features

The feature Direct Dialing In (DDI)permits direct inward dialing tosubscribers hooked up to a privatebranch exchange (PBX). In thiscase, the calling subscriber dialsthe direct inward dialing numberimmediately after the PBX directorynumber.

The Line Hunting (LH) featuremakes it possible to search for freelines in private branch exchanges.The search can be performed invarious different orders, e.g. se-quential search.

Conference features /Multi-party features

With the feature Explicit CallTransfer (ECT), a subscriber cantransfer calls to a third party. Beforetransfer, a connection must be setup to the third party. Call transfer forincoming calls is possible as soon asthe telephone begins to ring.

The featureThree-party Conference(TPC) enables a subscriber to holdan existing call and to set up a con-nection to another subscriber. Theinitiating subscriber can switchback and forth between the twocalls, terminate one of the calls orconnect all calls to form a three-party conference.

With the feature Large Conference(LC), up to 32 subscribers can beconnected to form a single discus-sion group.

The feature Subscriber HuntingGroup is an extention of thenormal Line Hunting feature. Itpermits a network operator tocombine existing subscribershaving analog subscriber access,ISDN basic access and ISDN pri-mary rate access in a subscriberhunting group. The followinghunting principles are sup-ported:

– sequential search

– circular search

– universial call distribution

– not sequential search

With the Test Data Messagefeature, analog subscribers cancheck the correct operation oftheir terminal display. The testmessage is sent in the on-hookstate.

EWSD

Subscriber Hunting Group

Analog

ISDN-BA

ISDN-PA

2 channels

SHG

S

O NT

PA equip-ment

1 channel

30 channels

18

The Telemeeting feature makes itpossible for subscribers to rent aprivate telephone conference circuitfor a predefined period from theoperator. The directory number foraccessing the telephone confer-ence is not public and is only givento the desired group of participants.Up to 7 parties can take part simul-taneously in a telemeeting confer-ence.

Call charge features

Using the feature Automatic VerbalAnnouncement of Charges, asubscriber can have the charges forthe last call announced at the endof the call.

The feature Reverse ChargingSystem (RCS) permits a callingsubscriber to initiate a call for whichthe called subscriber is charged. Areverse-charge call is requested bymeans of a specific feature code.The called subscriber is informedthat he or she is to be charged forthe call.

With the feature Reverse ChargeCall Rejection (RCCR), called sub-scribers (e.g. hotels) can protecttheir lines against calls for whichthey are expected to accept thecharges.

With the feature SubscriberCharge Indication, a subscribercan have the charges incurred for acall transmitted in the form ofmeter pulses (12 kHz, 16 kHz). Thesubscriber must be equipped witha suitable terminal for display ofthis information.

Special subscriber features

With the feature Alarm Call Service(ACS), a subscriber can receive awake-up call at a time specified inadvance. Such an alarm call is possi-ble on a one-off basis or repeatedlyat the same time over a number ofconsecutive days. In case of regularalarm calls, certain days of the weekcan be specified over consecutiveweeks.

The feature Automatic FeatureSubscription allows subscribersto assign themselves featuresfrom the feature package madeavailable by the operating com-pany. Feature administrationtakes the form of a user-friendlyvoice-controlled and announce-ment-driven dialog.

EWSD

Access Code IVPS Dialog

List of features:

Automatic RecallCall Forwarding UnconditionalCall Forwarding on no ReplyCall Forwarding on BusyCalling Line Identification PresentationThree-party Conference

Subscriber 4711:

Feature 1...Feature n

4711

Automatic Feature Subscription

19

Individual lines (e.g. analog, ISDN)can be grouped together with thefeature Closed User Group(CUG). As a rule, subscribers in aclosed user group are subject tocertain traffic restrictions. Thismeans that they can communicatewith each other, but communica-tion with subscribers outside of theclosed user group is only possiblewith the appropriate authorization.

The Feature Control Offline(FCOFF) feature provides the sub-scriber with user-friendly featurecontrol (activation, deactivation,status inquiry) with the help of avoice-controlled and announce-ment-driven dialog.

The General Facility Reset (GFR)feature enables the subscriber toreset various activated features bymeans of subscriber controlledinput only.

With the Keyword feature, a sub-scriber can specifically protect hisor her line. The subscriber canthereby prevent unauthorized featureusage on this line. Subscribers arefree to administer their keywordthemselves.

The feature Malicious Call Identi-fication (MCI) is used to identifymalicious or repeatedly annoyingcallers. The subscriber can activatethis feature manually during an ex-isting call or within a certain periodof time following the end of thecall. Automatic activation is possi-ble immediately on call acceptanceor as soon as the telephone startsringing. If a specific directory num-ber is under suspicion, callers canbe monitored in respect of this par-ticular number.

The feature Nailed-up Connection(NUC) provides semipermanentpoint-to-point connections betweentwo lines.

The feature Remote Control ofSupplementary Services (RCSS)provides subscribers with featureadministration for their own linefrom any line within the network.This feature therefore provides theanalog subscriber with remote con-trol of the call forwarding featuresand of traffic restrictions.

The Terminal Portability (TP) fea-ture allows a called subscriber todisconnect the terminal from onetelephone socket and plug it intoanother socket within a predefinedtime during an active call. The con-nection remains intact.

The feature Voice Data Protectionallows a subscriber to easily deacti-vate and reactivate those services(e.g. Call Waiting) that can interferewith data transmission (by injectingtones).

20

Operating company features

The Access Barring feature permitsthe operating company or the sub-scriber to block a line for incomingtraffic, outgoing traffic or for all traffic.The following blocking variants arepossible: Account Suspension,Maintenance Blocked, RequestSuspension Originating, RequestSuspension Terminating.

With the feature AdministrativeInterception of Calls, unsuccessfulconnections can be diverted to anoperator, to an announcement or toa special information tone. This canhappen, for instance, when a direc-tory number has been changed orif the requested service is notavailable.

The feature Coinbox TelephoneService makes it possible to set upoutgoing and incoming calls frompublic telephones. A special checkcan be made to ensure that the op-eration of these lines has not beenimpaired (e.g. as a result of damage).

The feature Emergency CallService (ECS) supports fast andsimple call setup in case of emer-gency, e.g. to the fire departmentor the police. After dialing a stan-dard emergency number, the sub-scriber is automatically connectedto the nearest emergency center. Asubscriber can always set up a con-nection to the emergency number,even if his/her line is blocked foroutgoing calls.

The Line Lockout feature is usedto monitor lines for faulty behavior,e.g. permanent loop interruption.

With the No Charge Calls feature,the operating company can permitcertain calls to be made without in-curring any charges.

With the feature PreferenceCategory During Catastrophe,the operating company can restrictoutgoing traffic to certain prioritysubscribers (e.g. police, fire depart-ment, etc.) if necessary. Incomingtraffic is not affected by this feature.

With the Priority feature, the oper-ating company can provide prefer-ential treatment for call setup to orfrom certain directory numbers. Ifall outgoing trunks are busy, the callattempt is automatically repeatedat specified intervals.

With the Trunk Offering feature,the operator can intervene in anexisting connection, for example, tooffer a subscriber a waiting inter-continental call or to check the busystatus of a subscriber line.

The feature No Trunk Offering canbe used to prevent trunk offering.

21

AD

SS

fe

atu

re s

pe

ctru

m Subscriber features forincoming calls

Call Forwarding (CF)

Call Forwarding Controlled byOperator (CFCO)

Call Forwarding to a FixedAnnouncement (CFFA)

Call Forwarding to a Group of Announcements (CFGA)

Call Forwarding to an Operator(CFO)

Call Forwarding to a Voice MailService (CFVMS)

Message Waiting Indication(MWI)

Multiple Simultaneous CallForwarding (MSCF)

Call Waiting (CW)

Call Waiting Deluxe (CWD)

Distinctive Call Waiting (DCW)

Distinctive Ringing (DR)

Do Not Disturb (DND)

Multiple Subscriber Number(MSN), Different Ringing

Parallel Ringing (PRNG)

Rejection of Forwarded Calls(RFC)

Selective Call Acceptance (SCA)

Selective Call Forwarding (SCF)

Selective Call Rejection (SCR)

Selective Call Waiting (SCW)

Selective Ringing (SR)

Series Completion Service (SCS)


Abbreviated Dialing (ABBD)

Automatic Recall (AR)

Call Completion to BusySubscriber (CCBS)

Call Completion on no Reply (CCNR)

Fixed Destination Call (FDC)

Selective Call Originating (SCO)

Subaddressing (SUBA)

Call Barring

Display features


Called Line IdentificationRestriction (CALR)

Calling Line IdentificationPresentation (CLIP)

Calling Line IdentificationRestriction (CLIR)

Calling Name IdentificationPresentation (CNIP)

Calling Name IdentificationRestriction (CNIR)

Connected Line IdentificationRestriction (COLR)

Calling Line Identification forWaiting Subscribers (CLICW)

Test Data Message

PBX features

Direct Dialing In (DDI)

Line Hunting (LH)

Subscriber Hunting Group (SHG)


Explicit Call Transfer (ECT)

Three-party Conference (TPC)

Large Conference (LC)

Telemeeting


Automatic Verbal Announce-ment of Charges

Reverse Charging System (RCS)

Reverse Charge Call Rejection(RCCR)

Subscriber Charge Indication


Alarm Call Service (ACS)


Closed User Group (CUG)

Feature Control Offline (FCOFF)

General Facility Reset (GFR)

Keyword

Malicious Call Identification (MCI)

Nailed-up Connection (NUC)

Remote Control of Supple-mentary Services (RCSS)

Terminal Portability (TP)

Voice Data Protection


Access Barring

Administrative Interception of Calls

Coinbox Telephone Service

Emergency Call Service (ECS)

Line Lockout

No Charge Calls

Preference Category DuringCatastrophe

Priority

Trunk Offering

No Trunk Offering

22

ISDNIntegrated Services Digital Network

The number of lines connected tothe integrated services digital net-work (ISDN) is growing rapidly.EWSD provides its ISDN sub-scribers with a large number ofuser-friendly features. Comparedwith the ADSS feature range, ISDNfeatures offer a wider scope of pos-sibilities. They also include someadditional features that are not pos-sible with analog lines.

Bearer Services

The bearer services are responsiblefor network-wide transmission ofinformation between two ISDN ter-minals. The transmission character-istics are in keeping with the OSIreference model (7-layer referencemodel for Open System Intercon-nection).

Bearer services are divided into thefollowing circuit and packet-switched services:

– Circuit Mode, Speech

– Circuit Mode,64 kbit/s unrestricted

– Circuit Mode, 3.1 kHz audio

– Packet Mode, SemipermanentB Channel Access

– Packet Mode, B Channel Access

– Packet Mode,Switched B Channel Access

– Packet Mode,D Channel Access

Teleservices

The teleservices are responsible forend-to-end communication. Thecommunication functions includeall transmission functions and com-munication protocols of the OSIreference model for controlling thedifferent communication processes.

Teleservices are divided into:

– Telephony, 3.1 kHz

– Telephony, 7 kHz

– Teletex

– Telefax (Group 4)

– Videotex

– Videotelephony


Using the Call Forwarding (CF)feature, a subscriber can forwardincoming call requests to any de-sired destinations.Calls can be forwarded either im-mediately (Call Forwarding Uncon-ditional, CFU), when there is noreply (Call Forwarding on no Reply,CFNR) or when the line is busy(Call Forwarding on Busy, CFB).When a subscriber has activatedcall forwarding, an announcementcan be used to inform calling par-ties that their call request is beingforwarded. For the individual callforwarding types CFU, CFNR, CFB,different call forwarding destina-tions can be reached independentlyof each other.

With the feature Call Forwardingto a Fixed Announcement (CFFA),a subscriber can forward incomingcall requests to a specific an-nouncement. Calls can be for-warded either immediately or aftera predefined period of time. Duringthis waiting time the forwardingsubscriber can still accept the call.


With the feature Call Forwardingto an Operator (CFO), a subscribercan forward all incoming call re-quests to an operator. Calls can beforwarded either immediately orafter a predefined period of time.During this waiting time the for-warding subscriber can still acceptthe call.


23



The feature Multiple SimultaneousCall Forwarding (MSCF) supple-ments the Call Forwarding (CF)feature. Up to 64 incoming call re-quests can be forwarded simulta-neously to a specified destination(e.g. to a voice mail service).

The Call Waiting (CW) featuremakes it easier to reach a subscriber.This feature notifies an ISDN sub-scriber with two busy channels thatup to two other subscribers are try-ing to set up a connection to his orher line. The ISDN subscriber canthen accept, reject or ignore a wait-ing call.

With the Call Deflection (CD) fea-ture, incoming call requests are di-verted to a previously definedsubscriber if the called subscriberdoes not wish to accept the offeredcall. Forwarding can take place im-mediately, without ringing (as forCall Forwarding Unconditional, CFU)or after being requested by the calledsubscriber during the ringing phase.In case of call deflection on re-quest, the subscriber can decideduring the ringing stage whether toaccept the call or to have it di-verted. The ISDN subscriber canset up call deflection individually forevery service and for every terminalconnected to the basic access.

EWSD

B29999

CF active

B14711

Ringing time

A


Subscriber 4711:

CFU .............................CFNR 9999CFBS ............................

S

O

NT

Operator

24


With the feature Multiple Sub-scriber Number (MSN), up to 99different directory numbers can beassigned to one ISDN access line.This makes it possible to reach thedifferent specific terminals and ser-vices on a basic access line. EWSDtreats each multiple subscribernumber as an independent directorynumber to which features can alsobe assigned on an individual basis.





The feature Rejection of Forwar-ded Calls (RFC) enables sub-scribers to automatically rejectcall requests forwarded to them.

EWSD

B1

RFC active

STOP

A

B2


CF active

S O NT

25

With the feature Selective CallWaiting (SCW), waiting call re-quests from defined directory num-bers are indicated to the calledsubscriber by means of differentcall waiting tones. The subscribercan define up to 50 directory num-bers. It is also possible to specifypartial directory numbers.

ISDN subscribers can use theSubaddressing (SUBA) feature toadd additional digits to their stan-dard ISDN directory number.Callers can then use these addi-tional digits, for example, to reacha specific terminal of an ISDNsubscriber. The authorization forsubaddressing can be specified in-dividually for each service.


With the Abbreviated Dialing(ABBD) feature, a subscriber candraw up an individual abbreviateddialing list. The directory numberschosen are assigned an abbreviatednumber in the list. The connectioncan then be set up by simply dialingthe abbreviated number. During callsetup, EWSD automatically convertsthe abbreviated number into thefull directory number.

The feature Call Completion toBusy Subscriber (CCBS) enablesthe subscriber to ring back auto-matically. The calling subscriberactivates this feature when thecalled subscriber is busy. The net-work then indicates by means ofrecall as soon as the called partyhas become available. If the callingparty accepts this ringback call,EWSD automatically sets up theconnection once again to the calledsubscriber.For an ISDN subscriber, a waitinglist can hold up to five unansweredcalls.

The feature Call Completion on noReply (CCNR) also enables thecalling subscriber to ring back auto-matically. The calling subscriber ac-tivates this feature when the calledparty does not reply. The networkthen indicates by means of recall assoon as the called party becomesactive again (e.g. when he/she isfree again after initiating a call).If the calling party accepts this ring-back call, EWSD automatically setsup the connection once again tothe called subscriber.For an ISDN subscriber, a waitinglist can hold up to five unansweredcalls.



The Call Barring feature enablesthe subscriber to protect his or herline from unauthorized use.The op-erating company can specify up to32 traffic restriction classes, fromwhich the subscriber is free tochoose a suitable one. In addition, acode-dependent restriction is alsopossible for prevention of unautho-rized feature usage on a line.

26

Display features

With the feature Calling Line Iden-tification Presentation (CLIP), acalled subscriber can request displayof the calling party’s directorynumber.


With the feature Connected LineIdentification Presentation (COLP),a calling ISDN subscriber can re-quest display of the called party’sdirectory number.

With the feature Connected LineIdentification Restriction (COLR),a called subscriber can suppressdisplay of his or her directory numberfor the calling subscriber.

The feature User-to-User Signaling(UUS) enables an ISDN subscriberto exchange certain additional infor-mation with another subscriberduring call setup, call release or dur-ing the call itself.This information istransmitted over the D channel.


EWSD

ACR active

CLIR active

announce-ment:

_ _ _ _


_ _ _ _

The calledparty needs your directory number

S

O

NT

27

PBX features

The feature Direct Dialing In (DDI)permits direct inward dialing tosubscribers hooked up to a privatebranch exchange (PBX). In thiscase, the calling subscriber dialsthe direct inward dialing numberimmediately after the PBX directorynumber.

The Line Hunting (LH) featuremakes it possible to search for freelines on ISDN basic accesses orISDN primary rate accesses to pri-vate branch exchanges. The searchcan be performed in various differ-ent orders, e.g. sequential search.

With the Partial Rerouting feature,an ISDN PBX subscriber can divertcall requests from the PSTN to an-other destination in the PSTN.

The feature Sharing of PrimaryRate Access by Several PBXsmakes it possible to distribute anISDN primary rate access overseveral private branch exchanges(PBX) with different pilot directorynumbers.

The feature Subscriber HuntingGroup is an extention of thenormal Line Hunting feature. Itpermits a network operator tocombine existing subscribershaving analog subscriber access,ISDN basic access and ISDN pri-mary rate access in a subscriberhunting group. The followinghunting principles are sup-ported:

– sequential search

– circular search

– universial call distribution

– not sequential search

EWSD

Subscriber Hunting Group

Analog

ISDN-BA

ISDN-PA

2 channels

SHG

S

O NT

PA equip-ment

1 channel

30 channels

28


The Call Hold (CH) feature enablesan ISDN subscriber to interrupt anactive call in order to set up a sec-ond call to another subscriber, toaccept a waiting call or to initiate asupplementary service. The sub-scriber can then alternate betweenthe active and the held connection

With the feature Explicit CallTransfer (ECT), a subscriber cantransfer calls to a third party. Beforetransfer, a connection must be setup to the third party. Call transfer forincoming calls is possible as soon asthe telephone begins to ring.


With the feature Large Conference(LC), up to 32 subscribers can beconnected to form a single discus-sion group.


The feature Advice of Charge(AOC) permits an ISDN subscriberto be notified of the charges in-curred for each individual call. Thecall charge information can betransmitted at the beginning of thecall, during the call, and at the endof the call.

The feature Reverse ChargingSystem (RCS) permits a callingsubscriber to initiate a call for whichthe called subscriber is charged. Areverse-charge call is requested bymeans of a specific feature code. Adisplay informs the called subscriberthat he or she is to be charged forthe call.




Individual lines (e.g. analog, ISDN)can be grouped together with thefeature Closed User Group(CUG). As a rule, subscribers in aclosed user group are subject tocertain traffic restrictions. Thismeans that they can communicatewith each other, but communicationwith subscribers outside of theclosed user group is only possiblewith the appropriate authorization.


29

The Feature Control Offline(FCOFF) feature provides the sub-scriber with user-friendly featurecontrol (activation, deactivation,status inquiry) with the help of avoice-controlled and announce-ment-driven dialog.


With the Keyword feature, asuscriber can specifically protecthis or her line. The subscriber canthereby prevent unauthorized fea-ture usage on this line. Subscribersare free to administer their keywordthemselves.


The feature Nailed-up Connection(NUC) provides semipermanentpoint-to-point connections betweentwo lines.

The feature Remote Control ofSupplementary Services (RCSS)provides subscribers with featureadministration for their own linefrom any line within the network.

The Terminal Portability (TP) fea-ture allows a called subscriber todisconnect a terminal from onetelephone socket of an ISDN basicaccess and plug it into anothersocket within a predefined timeduring an active call. The connec-tion remains intact.

EWSD

Access Code IVPS

Dialog

List of features:


4711


S

O NT

Subscriber 4711:


30



With the feature AdministrativeInterception of Calls, unsuccessfulconnections can be diverted to anoperator, to an announcement or toa special information tone. This canhappen, for instance, when a direc-tory number has been changed orif the requested service is notavailable.

The feature Emergency CallService (ECS) supports fast andsimple call setup in case of emer-gency, e.g. to the fire departmentor the police. After dialing a stan-dard emergency number, the sub-scriber is automatically connectedto the nearest emergency center. Asubscriber can always set up a con-nection to the emergency number,even if his/her line is blocked foroutgoing calls.

The Line Lockout feature is usedto monitor lines for faulty behavior,e.g. permanent loop interruption.

With the No Charge Calls feature,the operating company can permitcertain calls to be made without in-curring any charges.



31

ISD

N f

ea

ture

sp

ect

rum Bearer Services

Circuit Mode, Speech

Circuit Mode,64 kbit/s unrestricted

Circuit Mode, 3.1 kHz audio

Packet Mode, Semipermanent B Channel Access

Packet Mode, B Channel Access

Packet Mode,Switched B Channel Access

Packet Mode, D Channel Access

Teleservices

Telephony, 3.1 kHz

Telephony, 7 kHz

Teletex

Telefax (Group 4)

Videotex

Videotelephony

Mixed Mode



Courtesy Call


Call Forwarding to a FixedAnnouncement (CFFA)

Call Forwarding to a Group of Announcements (CFGA)





Call Waiting (CW)

Call Deflection (CD)


Multiple Subscriber Number(MSN)






Selective Call Waiting (SCW)





Call Completion on no Reply (CCNR)



Call Barring

Display features




Connected Line IdentificationPresentation (COLP)


User-to-User Signaling (UUS)

PBX features

Direct Dialing In (DDI)

Line Hunting (LH)

Line Hunting, Reaching SingleDevices by their MSN

Partial Rerouting

Sharing of Primary Rate Accessby Several PBXs

Conference features / Multi-party features

Call Hold (CH)



Large Conference (LC)


Advice of Charges (AOC)






Closed User Group (CUG)



Keyword


Nailed-up Connection (NUC)

Remote Control of Supple-mentary Services (RCSS)



Access Barring

Administrative Interception of Calls

Emergency Call Service (ECS)

Line Lockout

No Charge Calls


Priority

With GeoCENTREX (central officeexchange service), EWSD canprovide a comprehensive range offeatures for customized solutionsof PBX functions in the publicswitched telephone network (PSTN).GeoCENTREX is an integral compo-nent of EWSD, thereby ensuringthe service is provided with maxi-mum reliability.

GeoCENTREX is much more flexiblethan conventional PBXs. For in-stance, the subscribers of a Geo-CENTREX group are not bound toone particular location. Nevertheless,they still have access to all thecommon functions provided by afixed-location PBX.

The maximum number of sub-scribers that can belong to a Geo-CENTREX group is identical with thenumber of subscribers connectedto the public network, i.e. there isvirtually no limit. Existing PBXs canalso be included in a GeoCENTREXgroup. Given the wide range ofGeoCENTREX features and theways in which they can be com-bined, solutions can be drawn upon a customer-specific basis. Fea-tures for subscribers in the PSTNcan also be used by GeoCENTREXsubscribers.

The Call Center function of Geo-CENTREX meets one of today’sspecial demands. A large numberof companies are planning to improvetheir customer service by settingup a call center. In this respect,GeoCENTREX has fundamental so-lutions for meeting a company’spresent and future requirements.

Apart from its functional advantages,GeoCENTREX also offers clear ad-vantages in terms of costs. For theend customer, in particular, savingsare made in the connection costs andother costs associated with an ex-pensive PBX (e.g. leasing of premises,maintenance and administration).

32

GeoCENTREXCentral Office Exchange Service

33

The GeoCENTREX function spec-trum is divided into:

• GeoCENTREX group features

GeoCENTREX proposes a groupstructure for the purpose oforganizing subscribers. Groupscan be formed on a local or net-work-wide basis. The group fea-tures provide additional optionsfor the administration of theGeoCENTREX groups.

• GeoCENTREX subscriberfeatures

GeoCENTREX subscriber featurescan be assigned individually toeach subscriber of a Geo-CENTREX group. In principle,each GeoCENTREX subscribercan also access those featuresthat can be used by a subscriberin the PSTN.

• Attendant Features

GeoCENTREX groups are oper-ated via GeoCENTREX attendantstations. The attendant stationscan also be organized into groups;up to 4,095 attendant groupscan be set up per EWSD net-work node. Administration is onlypossible for local GeoCENTREXgroups.

GeoCENTREX group features

A GeoCENTREX group can beused to pool together subscribersthat have a common numberingplan and a common feature spec-trum. The GeoCENTREX group isrestricted to subscribers on thesame EWSD network node.

A number of GeoCENTREX groupscan be pooled together to form abusiness group. A business groupcan extend throughout the networkover several EWSD network nodes.Business groups are therefore par-ticularly suited for companies thatare present in several locations.

Sub-business groups can beformed within individual businessgroups. A specific feature spectrumcan be defined for the subscribersorganized within such a sub-businessgroup. A sub-business group mayalso extend over several EWSDnetwork nodes.

GeoCENTREX groups can also becreated as mini groups of sub-scribers that primarily initiate callsto the PSTN. To this end, the sub-scribers are given special accessrights.The subscribers can conducttheir external calls directly (withouthaving to dial an access code). Forinternal calls, however, an accesscode is necessary.

Within one EWSD network node, anumber of GeoCENTREX groups canshare the same attendant group,e.g. for common administration,call-charge handling, data manage-ment and traffic data administration.The attendant group and the Geo-CENTREX groups it serves togetherform a GeoCENTREX complex.

Thanks to its flexible group size,GeoCENTREX can meet the needsof all customers. Up to 3,000 Geo-CENTREX groups are administeredin one EWSD network node. Themaximum number of subscribers inall GeoCENTREX groups is restrictedonly by the maximum number ofsubscribers that can be connectedto the EWSD network node.

Each GeoCENTREX group has agroup-specific private numberingplan. The GeoCENTREX privatenumbering plan comprises localinternal directory numbers as wellas network-wide internal directorynumbers.A local internal directory numbercan be used to reach destinationswithin the same GeoCENTREXgroup.A network-wide internal directorynumber can be used to reach desti-nations within a business group.

With the group dialing feature, anaccess code can be specified forthe GeoCENTREX group. Using thisaccess code, followed by the internaldirectory number, a GeoCENTREXsubscriber not belonging to thegroup can reach any subscriberwithin this local GeoCENTREXgroup.

Special access codes can be de-fined within a private numberingplan, e.g. for accessing the PSTN,using private devices, connectingto the attendant.

The GeoCENTREX feature codesare used on a group-specific basisto activate, deactivate, interrogateand use the GeoCENTREX features.

34

GeoCENTREX makes it possible topool together subscriber-equivalentPBX hunting groups to form Multi-Line Hunting Groups. Specialhunting methods exist for thesearch for free lines.Incoming calls to subscriber-equiva-lent PBX hunting groups can beheld by means of a queuing functionwhenever no free line is available inthe multi-line hunting group.

The EWSD intercept codes areused for handling unsuccessfulconnections. In addition, group-specific announcements and tonescan be set for internal calls.

Call charges are recorded forGeoCENTREX in the same way asin the PSTN. To this end, EWSDprovides the automatic messageaccounting (AMA) and periodic pulsemetering (PPM) methods. Apartfrom the usual details, the AMAdata records for GeoCENTREX sub-scribers can also contain informationthat is specific to GeoCENTREX.In contrast to the zoning in the pub-lic network, GeoCENTREX group-specific zoning makes it possible toadapt an internal connection (localor network-wide) to the conditionsof GeoCENTREX. Different callcharge rates can be specified forgroup-internal and cross-group calls.Subscribers, PBXs and attendant-positions within a GeoCENTREXgroup can be divided into callcharge areas.

EWSD offers specific types of trafficmeasurement for GeoCENTREX.These can be used in addition to thestandard measurement for analogsubscribers and ISDN subscribers.

GeoCENTREX comprises the com-plete line spectrum for analogsubscribers and ISDN subscribers.

Analog individual lines or ISDNbasic accesses and PBXs can begrouped together with the featureClosed User Group (CUG). As arule, subscribers in a closed usergroup are subject to certain trafficrestrictions. This means that theycan communicate with each other,but communication with sub-scribers outside of the closed usergroup is only possible with the ap-propriate authorization.CUGs can be created in parallel toGeoCENTREX groups. GeoCEN-TREX subscribers can also bemembers of a CUG. Existing Geo-CENTREX traffic restrictions arethen added to the CUG traffic re-strictions.

The feature Nailed-up Connections(NUC) can also be used with Geo-CENTREX. A nailed-up connection ispossible between subscribers withinthe same GeoCENTREX group aswell as between a GeoCENTREXsubscriber and a subscriber in thePSTN.

Using the feature SimulatedFacility Groups, the number ofsimultaneous calls with thePSTN can be restricted. Thisaffects calls both from and to aGeoCENTREX group.

Simulated Facility Groups

EWSD

limited

GeoCENTREX

Group

PSTN

35

GeoCENTREX subscriberfeatures

GeoCENTREX includes subscriberfeatures for:

• Basic functions

• Call setup

• Call allocation

• Call control

• Call forwarding

• Call restrictions

• ISDN services

• Call display

• Call security

• Alarm call services

• Call tracing functions

• Call charging

Basic functions

GeoCENTREX offers the possibilityof authorizing specific features on asubscriber-individual basis by meansof an access code. The featuresrequiring such authorization can begrouped together. Usage of the fea-tures contained in an authorizationgroup is controlled by means of aCustomer Access TreatmentCode (CATCODE).

Calls to the PSTN can be made viaa specific network operator. In thiscase, the network operator isselected by means of a certainCarrier Access Code (CAC).

A GeoCENTREX subscriber canuse the function Directory NumberPortability (DNP) in the same wayas a subscriber connected to thePSTN.

The feature Subscriber EmergencyOverride enables those Geo-CENTREX subscribers barred frommaking external calls to access anemergency center in case of anemergency. The call is set up bymeans of the access code for callsto the PSTN, followed by the emer-gency number in question.

The Feature Control Offline(FCOFF) feature provides thesubscriber with user-friendly fea-ture control (activation, deactiva-tion, status inquiry) with the helpof a voice-controlled and an-nouncement-driven dialog.


EWSD

Access Code IVPS Dialog

List of features:


Subscriber 4711:


4711


36


With the feature Multiple Sub-scriber Number (MSN), up to 99different directory numbers can beassigned to one ISDN access line.This makes it possible to reach thedifferent specific terminals and ser-vices on a basic access line. EWSDtreats each multiple subscribernumber as an independent directorynumber to which features can alsobe assigned on an individual basis.

With the Keyword feature, a sub-scriber can specifically protect hisor her line. The subscriber canthereby prevent unauthorized fea-ture usage on this line. Subscribersare free to administer their keywordthemselves.


Using the feature Subscriber Con-trolled Input (SCI), a subscriber ofa GeoCENTREX group can activate,deactivate, modify and interrogatefeatures for his or her line.

The Terminal Portability (TP) fea-ture allows a called subscriber todisconnect the terminal from onetelephone socket and plug it intoanother socket within a predefinedtime during an active call. The con-nection remains intact.


Call setup

With the Abbreviated Dialing(ABBD) feature, a GeoCENTREXsubscriber can draw up an abbrevi-ated dialing list, or the attendantcan provide such an abbreviateddialing list.The internal, national or internationaldirectory numbers chosen are eachassigned an abbreviated number inthe list. To set up a connection, theabbreviated access code must bedialed in addition to the abbreviatednumber. EWSD automatically trans-lates the abbreviated number intothe full-length directory numberwhen the connection is set up. AGeoCentrex abbreviated dialing listcan be used individually by just onesubscriber or made available toseveral subscribers.


Call allocation

With the Automatic Recall (AR)feature, a called analog subscriberis able to initiate the last call thatcould not be set up originally (e.g.because the call was terminated bythe calling party).The subscriber ac-tivates recall by dialing the appro-priate feature code. EWSD thenautomatically sets up the recallconnection.

The feature Call Completion toBusy Subscriber (CCBS) enablesthe subscriber to ring back auto-matically. The calling subscriberactivates this feature when thecalled subscriber is busy. The net-work then indicates by means ofrecall as soon as the called partyhas become available. If the callingparty accepts this ringback call,EWSD automatically sets up theconnection once again to the calledsubscriber.

The busy subscriber may be con-nected in the same GeoCENTREXgroup, in another GeoCENTREXgroup or in the PSTN. A waiting listcan contain one unanswered callfor an analog subscriber and up tofive unanswered calls simultane-ously for ISDN subscribers.

If required, the subscriber usingAutomatic Recall can arrange forthe directory number of the sub-scriber who is being re-called tobe announced or displayed onan appropriate terminal.

37

The feature Call Completion on noReply (CCNR) enables the callingsubscriber to ring back automati-cally.The calling subscriber activatesthis feature when the called partydoes not reply. The network thenindicates by means of recall assoon as the called party becomesactive again (e.g. when he/she isfree again after initiating a call).If the calling party accepts this ring-back call, EWSD automatically setsup the connection once again tothe called subscriber.

The subscriber not replying maybe connected in the same Geo-CENTREX group, in another Geo-CENTREX group or in the PSTN. Awaiting list can contain one unan-swered call for an analog sub-scriber and up to five unansweredcalls simultaneously for ISDN sub-scribers.

With the feature Call Pick-up(CPU), a GeoCENTREX subscribercan accept a call request that arriveson another line of the same Geo-CENTREX group. For call pick-upwithin a GeoCENTREX group, callpick-up groups can also be formed,whereby a number of calls queueup simultaneously for acceptance.

The Call Waiting (CW) featuremakes it easier to reach a sub-scriber. It indicates to a subscriberthat other subscribers are attempt-ing to establish a connection to himor her. In case of a busy analogGeoCENTREX subscriber, one callcan be waiting at any one time. Fora busy ISDN subscriber, however,there can be up to two more wait-ing calls. The GeoCENTREX sub-scriber can accept, reject or ignorea waiting call request.

Call Waiting (CW) for GeoCENTREXcan be restricted to calls from thePSTN only or calls from otherGeoCENTREX groups. Within aGeoCENTREX group, it is possibleto wait on a subscriber even if thatsubscriber has not activated theCall Waiting (CW) feature.

The feature Improved Paging en-ables attendants and other Geo-CENTREX subscribers to pagepartners within a GeoCENTREXgroup. The paged subscriber canaccept the call with a special formof call pick-up.

The feature Subscriber Barge-in(SBI) enables a GeoCENTREX sub-scriber to break into an existing callwithout interrupting the connec-tion. A warning tone is applied. TheGeoCENTREX subscriber dials anaccess code followed by the inter-nal number of the subscriber that isto be subject to intrusion.

With the feature Subscriber Barge-in Rejection (SBIR), a subscribercan prevent other subscribers fromintruding.

Call control

The Call Hold (CH) feature enablesan ISDN subscriber to interrupt anactive call in order to set up a secondcall to another subscriber, to accepta waiting call or to initiate a supple-mentary service. The subscribercan then alternate between the ac-tive and the held connection.

With the feature Explicit CallTransfer (ECT), a subscriber cantransfer calls to a third party. Beforetransfer, a connection must be setup to the third party. Call transfer forincoming calls is possible as soon asthe telephone begins to ring.For GeoCENTREX, call transfer canbe permitted for all calls or restrictedto either internal calls within thesame GeoCENTREX group, incom-ing calls from within and outsideof the GeoCENTREX group, exter-nal calls from outside of the Geo-CENTREX group, or calls to theattendant.

With the feature Secretarial CallTransfer, two separate calls can beset up and subsequently intercon-nected.

38


Call forwarding

Using the Call Forwarding (CF)feature, a subscriber can forward in-coming call requests to any desireddestinations.Calls can be forwarded either im-mediately (Call Forwarding Uncon-ditional, CFU), when there is noreply (Call Forwarding on no Reply,CFNR) or when the line is busy(Call Forwarding on Busy, CFB),only within the same GeoCENTREXgroup or business group/sub-busi-ness group, or only for incomingcalls from outside of the GeoCEN-TREX group. When a subscriber hasactivated call forwarding, an an-nouncement can be used to informcalling parties that their call requestis being forwarded. For the individ-ual call forwarding types CFU,CFNR, CFB, different call forward-ing destinations can be reached in-dependently of each other.


The feature Call Forwarding toFixed Destinations permits callforwarding to destinations withinthe PSTN, such as 8 e.g. a fixedannouncement or a voice mailservice.

With the feature Call Forwarding toan Operator (CFO), a GeoCENTREXsubscriber can forward all incomingcall requests to an attendant. Callscan be forwarded either immedi-ately or after a predefined period oftime. During this waiting time theforwarding subscriber can still acceptthe call.



The feature Call Park enablesan analog GeoCENTREX sub-scriber within an network nodesto park a call and pick it up againfrom another line within thesame GeoCENTREX group.

Call parked

Call Park

EWSD

Geo

CENTREX Group

Call active

39


The feature Multiple SimultaneousCall Forwarding (MSCF) supple-ments the Call Forwarding (CF)feature. With an analog subscriber,up to 10 incoming call requests canbe forwarded simultaneously to aspecified destination (e.g. a voicemail service). In the case of anISDN subscriber, up to 64 incomingcall requests can be forwarded si-multaneously.

With the Call Deflection (CD)feature, incoming call requests arediverted to a previously definedsubscriber if the called subscriberdoes not wish to accept the offeredcall. Forwarding can take place im-mediately, without ringing (as forCall Forwarding Unconditional, CFU)or after being requested by the calledsubscriber during the ringing phase.In case of call deflection on request,the subscriber can decide duringthe ringing stage whether to acceptthe call or to have it diverted. TheISDN subscriber can set up calldeflection individually for everyservice and for every terminal con-nected to the basic access.

With the feature Default Call For-warding if Busy or No Reply(DCF), call requests from outsideof the GeoCENTREX group areautomatically forwarded if thecalled subscriber is busy or doesnot answer.The forwarding destina-tion can be another subscriber orthe attendant.

With the feature Music on Hold,music can be transmitted to sub-scribers put on hold for the durationof the holding time.

The feature Remote Control ofCall Forwarding (RCCF) providesa GeoCENTREX subscriber withremote control of call forwarding(CF) functions on his or her line.

With the feature Sequential CallForwarding, a call that has alreadybeen forwarded can be forwardedagain. A call can be forwarded up tofive times.

EWSD

B29999

CF active

B14711

Ringing timeA

Subscriber 4711:

CFU .............................CFNR 9999CFB ............................


GeoCENTREX

Group

Operator

40

Call restrictions


GeoCENTREX subscribers andsubscriber-equivalent PBXs can beassigned individual Call Restric-tions. The following restrictions arepossible: blocking for direct callsand blocking for attendant calls tothe PSTN, blocking for direct callsand general blocking for all callsfrom the PSTN.





The feature Rejection of Forwar-ded Calls (RFC) enables sub-scribers to automatically rejectcall requests forwarded to them.

Using the feature AuthorizationCode (ATC), a GeoCENTREXsubscriber can activate anddeactivate traffic restrictionscreated by the network opera-tor. The authorization code per-mits the subscriber to set upcalls within a local GeoCENTREXgroup from all blocked lines.


EWSD

ACR activeCLIR active

announce-ment:

_ _ _ _


GeoCENTREX

Group

The called party needs your directory number

41

The Call Barring feature enablesthe subscriber to protect his or herline from unauthorized use.The operating company can specifyup to 32 traffic restriction classes,from which the subscriber is free tochoose a suitable one. In addition, acode-dependent restriction is alsopossible for prevention of unautho-rized feature usage on a line.

ISDN services

The following bearer services canbe used with GeoCENTREX:




The teleservices that may be usedwith GeoCENTREX are:



– Teletex


– Videotex

– Videotelephony

ISDN subscribers can use the Sub-addressing (SUBA) feature to addadditional digits to their standardISDN directory number.Callers can then use these addi-tional digits, for example, to reacha specific terminal of an ISDNsubscriber. The authorization forsubaddressing can be specifiedindividually for each service.

The feature User-to-User Signaling(UUS) enables an ISDN subscriberto exchange certain additional infor-mation with another subscriberduring call setup, call release or dur-ing the call itself.This information istransmitted over the D channel.

EWSD

B1

CF active

RFC active

STOP

A

B2


GeoCENTREX

Group

EWSD

outgoing traffic restriction

Authorization Code (ATC)

GeoCENTREX

Group

STOP

Authorization Code

42

Call display

The feature Call Waiting Indica-tion notifies the subscriber thatanother call request is waiting.

With the feature Calling Line Iden-tification Presentation (CLIP), acalled subscriber can request dis-play of the calling party’s directorynumber.For internal calls, the GeoCENTREX-internal number is displayed; forexternal calls, the PSTN directorynumber is displayed.


The feature Calling Line Identifi-cation for Waiting Subscribers(CLICW) expands the possibilitiesof the Call Waiting (CW) feature.The subscriber receiving the waitingcall is shown the directory numberof the waiting subscriber as addi-tional information.

With the feature Connected LineIdentification Presentation (COLP),a calling ISDN subscriber can re-quest display of the called party’sdirectory number.

With the feature Connected LineIdentification Restriction (COLR),a called subscriber can suppressdisplay of his or her directory num-ber for the calling subscriber.

With the feature Calling NameIdentification Presentation (CNIP),a called GeoCENTREX subscriberor attendant can have the callingparty’s name displayed. For thisfeature, the subscribers’ namesmust have been stored in the net-work node of the calling subscriber.

With the feature Calling NameIdentification Restriction (CNIR),a calling GeoCENTREX subscriberor attendant can suppress displayof their name for the called sub-scriber. Certain subscriber groups(e.g. police) can be assigned specialpermission authorizing them toignore such suppression.

With the feature Connected NameIdentification Presentation(CONP), a calling GeoCENTREXsubscriber or attendant can displaythe name of the called subscriber.The name of the calling subscribermust be created in the associatednetwork node.

With the feature Connected NameIdentification Restriction (CONR),a called GeoCENTREX subscriberor attendant can suppress displayof their call data for the calling sub-scriber. Certain subscriber groups(e.g. police) can be assigned specialpermission authorizing them toignore such suppression.

With the feature Different Ringingit is possible to assign a specialringing sequence to certain incom-ing call requests. Application of theringing sequence depends on thedirectory number of the calling sub-scriber.

The Distinctive Ringing (DR) fea-ture enables the subscriber to dif-ferentiate between certain types ofconnections by means of differentringing sequences.For instance, the subscriber canrecognize forwarded calls or differ-entiate between national and inter-national calls or between callswithin a GeoCENTREX group andcalls from outside a GeoCENTREXgroup.


43

With the Selective Ringing (SR)feature, call requests from certaindefined directory numbers are sig-naled to the analog subscriber bymeans of different ringing se-quences.The subscriber can defineup to 50 directory numbers. It isalso possible to specify partial di-rectory numbers.

Call security

If a GeoCENTREX subscriber is tobe protected from intrusion by anattendant, the feature AttendantBarge-in Rejection (ABIR) can beassigned.

In the Distinctive Call Waiting(DCW) feature, different call waitingtones enable the subscriber to dif-ferentiate between different typesof waiting calls.For instance, the subscriber canrecognize forwarded calls or differ-entiate between national and inter-national calls.



The feature Voice Data Protectionallows a subscriber to easily deacti-vate and reactivate those services(e.g. Call Waiting) that can interferewith data transmission (by injectingtones).

Alarm call services


Call tracing functions


With the Test Data Messagefeature, analog subscribers cancheck the correct operation oftheir terminal display. The testmessage is sent in the on-hookstate.

EWSD

Access Code

T.D.M.

Test Data Message

GeoCENTREX

Group

Test Data Message

44

Call charging

A GeoCENTREX subscriber can beassigned an Account Code (ACC).Using this, the subscriber can dif-ferentiate the charges for outgoingcalls. Each preset account code canbe overwritten by the subscriber fora current call setup. The accountcode in each case also appears inthe AMA data record and in themessage detail recording (MDR)data record.

The feature Advice of Charge(AOC) permits an ISDN subscriberto be notified of the charges in-curred for each individual call. Thecall charge information can betransmitted at the beginning of thecall, during the call, and at the endof the call.

The feature No Charge Calls en-ables the operating company topermit certain calls that are free ofcharge.

Attendant features

The GeoCENTREX attendant fea-tures are divided into:

• Attendant group features

• Attendant station features

• Multifunctional attendantconsole features

Attendant group features

The Automatic Call DistributionSystem (ACD) distributes the in-coming calls among the availableand active attendant stations withinan attendant group.

The GeoCENTREX attendant groupscan be divided into various taskgroups. The distribution of incom-ing calls among the task groupscan be controlled on the basis ofthe call type.

The feature Group Make Busy(GMB) enables an attendant stationwith the corresponding authoriza-tion to block all stations belongingto the attendant group for the auto-matic call distribution system(ACD). This means that no morecalls can be transferred via ACD.

With the feature Link Failure CallDiversion (LFCD), all calls are auto-matically forwarded to a previouslydefined destination if all lines of aGeoCENTREX attendant grouphave failed.

The feature Reverse ChargingSystem (RCS) permits a callingsubscriber to initiate a call forwhich the called subscriber ischarged. A reverse-charge call isrequested by means of a spe-cific feature code.The called subscriber is in-formed that he or she is to becharged for the call.

EWSD


GeoCENTREX

Group BA reverse charges? Yes

45

The feature Night Service (NS)forwards all calls destined for anattendant group to a previouslydefined GeoCENTREX directorynumber. This forwarding becomesactive when the attendant groupcannot be reached, e.g. at night, atweekends and on holidays. Thenight service number can be as-signed to a certain subscriber or acertain attendant station within thelocal GeoCENTREX group. Directcalls to a particular attendant arestill possible.

Attendant station features

Using the feature Attendant Barge-in (ABI), an attendant can intrudeon an existing call without inter-rupting the connection.

The feature Attendant Camp On(ACO) enables the attendant totransfer an incoming call to a busyor an available GeoCENTREX sub-scriber located in the same busi-ness group as the attendantstation. A busy analog subscriber isnotified by means of a waitingtone; a busy ISDN subscriber is ad-ditionally informed by means of aterminal display. If the called sub-scriber does not answer, the call isautomatically returned to the atten-dant.

With the feature Attendant Emer-gency Override (AEO), the atten-dant can switch a call through to aGeoCENTREX subscriber if thissubscriber cannot be reached di-rectly from outside owing to atraffic restriction or active features,e.g. Do not Disturb or Call Forward-ing.

With the feature Logon for BasicAttendant Station, an attendantlogs on to a basic attendant stationfor the automatic call distributionsystem (ACD). From this time on,the attendant is transferred callsfrom the ACD. With the featureLogoff for Basic Attendant Station,an attendant logs off from the ACD.

An attendant can use the featurePosition Make Busy to mark astation such that the call distribu-tion system forwards no more callsto it. However, the attendant canstill accept direct calls and set upcalls at this station.

With the feature Post Call Time(PCT), the attendant is assigned anew call only after a certain blockingtime has elapsed since the previouscall was terminated (by parking, calltransfer, etc.). The attendant canuse this time to reaccept a previ-ously parked connection.

With the feature Rerouting withManual Acceptance Tone, a callrequest is forwarded if it has notbeen accepted by an attendantafter a certain predefined period oftime.The attendant station in ques-tion is then automatically markedas "Position make busy”.

Multifunctional attendantconsole features

With the feature Call Park ForAttendants, up to six calls can beparked at one attendant station.

The feature Call Presentation andAcceptance automatically indi-cates to the attendant those callsthat are transferred from the auto-matic call distribution system(ACD). The attendant must acceptthe call manually. For each atten-dant station, certain call types to beprocessed individually by this atten-dant station can be specified.

With the feature Call Type Identifi-cation, the attendant receives in-formation on calls that have justcome in and on the status of exist-ing connections.

With the feature Dial to Attendant,GeoCENTREX subscribers canreach the attendant by means of anaccess code.

Using the feature AttendantControl of Facilities, an atten-dant with the corresponding ad-ministrative authorization canblock all lines of a GeoCENTREXgroup for direct calls to thePSTN and unblock them again.

46

The feature Dial through Attendantpermits GeoCENTREX subscriberswho are blocked for direct calls tothe public network to make a callby dialing a feature code and the re-quired public directory number.Thecall distribution system forwardsthe connection to the MAC atten-dant, who controls the call setup tothe public network.

The attendant has two options:

– to allow the call with or withoutanswering (consultation withthe caller), or

– to answer the call and thenexplicitly set up the desiredconnection and transfer it to the GeoCENTREX subscriber.

All attendants in an attendant grouphave access to a common Direc-tory Assistance system. This isoperated by means of a PC towhich all attendants have access.

With the feature Logon for Multi-functional Attendant Console, anattendant logs on to a MAC for theautomatic call distribution system(ACD). From this time on, the at-tendant is transferred calls from theACD. With the feature Logoff forMultifunctional Attendant Con-sole, an attendant logs off from thecall distribution system.

The feature Message DetailRecording (MDR) provides de-tailed call information, thereby mak-ing it possible for GeoCENTREXcustomers to check the chargesincurred within the GeoCENTREXgroup. The call data records arethen transferred to the MAC,where they can be post-processed.This provides the possibility of, forinstance, separate call charging forhotel guests.

The feature Redial Last Numberstores the last directory numberdialed at the attendant station sothat it can be accessed for callingthe same number again.

With the feature Traffic DataHandling, the traffic statistics forthe various parameters of theGeoCENTREX group are displayedon a half-hourly basis.

With the Serial Call feature, theattendant can set up sequentialcalls to different internal andexternal partners. After eachcall, the subscriber is again con-nected to the attendant, whocan then set up the call to thenext subscriber.

The feature Online Traffic/ Per-formance Reports provides in-formation on the status andperformance of the attendantstation and on the traffic via thecall distribution system.

The feature EWSD DatabaseAdministration enables theadministration of a GeoCENTREXgroup (private numbering plan,GeoCENTREX subscriber fea-tures, restrictions).

47

Basic functions

Customer Access TreatmentCode (CATCODE)


Carrier Access Code (CAC)

Directory Number Portability(DNP)

Subscriber Emergency Override



Multiple Subscriber Number(MSN)

Keyword

Priority

Subscriber Controlled Input (SCI)



Call setup



Call allocation

Automatic Recall (AR)


Call Completion on no Reply(CCNR)

Call Pick-up (CPU)

Call Waiting (CW)

Improved Paging

Subscriber Barge-in (SBI)

Subscriber Barge-in Rejection(SBIR)

Call control

Call Hold (CH)


Secretarial Call Transfer

Call Park


Call forwarding



Call Forwarding to a Group ofAnnouncements (CFGA)

Call Forwarding to FixedDestinations





Call Deflection (CD)

Default Call Forwarding if Busyor No Reply (DCF)

Music on Hold

Remote Control of CallForwarding (RCCF)

Sequential Call Forwarding

Call restrictions

Access Barring


Authorization Code (ATC)

Call Restrictions






Call Barring

ISDN services

Bearer Services

Teleservices


User-to-User Signaling (UUS)

Call display

Call Waiting Indication



Calling Line Identification forWaiting Subscribers (CLICW)

Connected Line IdentificationPresentation (COLP)


Calling Name IdentificationPresentation (CNIP)

Calling Name IdentificationRestriction (CNIR)

Connected Name IdentificationPresentation (CONP)

Connected Name IdentificationRestriction (CONR)

Different Ringing

Distinctive Ringing (DR)


Selective Ringing (SR)

Test Data Message

Call security

Attendant Barge-in Rejection(ABIR)

Distinctive Call Waiting (DCW)



Voice Data Protection

Alarm call services


Call tracing functions


Call charging

Account Code (ACC)

Advice of Charge (AOC)

No Charge Calls


Ge

oC

EN

TR

EX

su

bsc

rib

er

fea

ture

sp

ect

rum

48

EWSD InterNodeInternet Supplementary Services

The combination of the Internetand the conventional telecommuni-cations network in the EWSD In-terNode results in a range ofhigh-quality supplementary services.These increase the availability ofthe subscriber, enhance the user-friendliness and expand the admin-istrative options for the line. Via theIN functionality of the EWSD it ispossible to make the Internet sup-plementary services available tosubscribers connected via networknodes of other manufacturers.

Internet supplementary services

Analog subscribers cannot bereached for incoming calls as longas they are connected to the Inter-net via their subscriber line. How-ever, with Call Waiting InternetBusy (CWIB), analog Internet sub-scribers receive a visual messageon their PC screen, informing themthat a call is waiting on the publictelephone network (PSTN). In thiscase, a subscriber is free to ignoreor accept the telephone call. If thecall is accepted, the Internet ses-sion is terminated.

The Internet supplementary serviceCall Completion Internet Busy(CCIB) is intended for subscribersusing Voice over Internet (VoI) ontheir PC. With Voice over Internetand Call Completion Internet Busy(CCIB), a subscriber currently onthe Internet can accept an incomingcall directly on the PC, without havingto interrupt the existing Internetconnection.

EWSD

Call Completion Internet Busy (CCIB)

PoP

IWU

PSTN

accept/ignore

Internet

CWIB

EWSD

Call Waiting Internet Busy (CWIB)

Internet

CW

PSTN

PoP

IWU

accept/ignore

49

The Internet supplementary serviceE-Mail Waiting Indication (EWI)informs a subscriber that a personalmessage (E-mail) is waiting on theInternet. This information is sent tothe subscriber either by means of aspecial dial tone or, provided a suit-able terminal is available, on a visualdisplay.

With the Internet supplementaryservice Improved Access to Voiceover Internet (IAVoI), the sub-scriber can also easily use the In-ternet for telephone calls. Voiceover Internet calls are set up via sin-gle-stage standard dial proceduresto the Internet, without the needfor additional dial-up stages and au-thorization codes. For Voice over In-ternet calls, the subscriber receivesclearly comprehensible informationon the call charge.There is the pos-sibility of having VoI connectionslisted on the monthly telephonebill. The call data is transferred inthe usual EWSD format to the post-processing systems.

Analog / ISDN

SS7

Internet

EWSD

EWSD

E-Mail Waiting Indication (EWI)

PoP

IWU

special dialtone or

messagedisplay

e-mail server

EWSD

Improved Access to Voice over Internet (IAVoI)

PoP

IWU

Internet

PoP

IWU

PSTN

50

With the Internet supplementaryservice Subscriber ControlledInput via Internet (ISCI), sub-scribers can use a web browser toperform menu-driven administrationand a visual check of their tele-phone subscriber features. Thisfunction is implemented by meansof a special ISCI web server thatuses standard Internet protocols tocommunicate with the Internetsubscriber, translates the subscriberinputs and transmits them to theEWSD.

EWSD

Subscriber Controlled Input via Internet (ISCI)

analog modem33.6 kbit/ 55.6 kbit Router

PoP

IWU

Internet

ISCI

server

ISDN card64 kbit/ 128 kbit

EW

SD

In

terN

od

e f

ea

ture

sp

ect

rum Internet supplementary

services

Call Waiting Internet Busy(CWIB)

Call Completion Internet Busy(CCIB)

E-Mail Waiting Indication (EWI)

Improved Access to Voice overInternet (IAVoI)

Subscriber Controlled Input via Internet (ISCI)

52

ININ Services in the Network Node

EWSD offers economical solutionsfor services that are otherwise onlyavailable in a classic intelligent net-work (IN).These IN services can beintroduced into any EWSD networknode by means of a software ex-pansion.

With EWSD and its exchange-based IN solution, even new oper-ating companies functioning solelyin the long-distance network havethe possibility of making theirtelecommunications services avail-able to subscribers in local traffic.

EWSD based IN services

With the Freephone service, it isthe called subscriber instead of thecalling subscriber that accepts thecharges for the connection. In thisway, free telephone calls can bemade to companies or mail orderfirms.

With the Reverse Charging service,a called subscriber can accept anycharges incurred by a calling sub-scriber without the intervention ofan operator. The called subscriberhas a certain period of time afteraccepting the call to decide whetheror not to accept the charges.

The Televoting service is used forvotes taken via the telephone net-work. The users of this service areusually radio orTV stations or marketresearch institutes.Those telephonesubscribers wishing to participatein the vote dial a specified directorynumber to register their vote oropinion. When the vote has beensuccessfully accepted, the caller re-ceives confirmation, e.g. in theform of an announcement.

EWSD SSP direct accessservices

With the service Selective ReverseCharging, subscribers can specifythe calling subscribers for whichthey will accept a reversal ofcharges.The list of such callers canbe administered by the actual sub-scriber. For instance, company em-ployees could be authorized tomake free telephone calls to thecompany headquarters.

With the service Time-DependentCall Forwarding, a subscriber canforward incoming calls to variousdestinations at different times ofthe day. For example, calls to a res-idential directory number could beforwarded to a business numberduring office hours, and calls to thebusiness number could be for-warded to the residential telephonenumber outside of office hours.

With the Global Series Com-pletion service, a called sub-scriber can be reached at anumber of terminals (e.g. in thefixed network and the mobilenetwork) by means of a singleservice directory number. If thesubscriber does not reply or aterminal is busy, the call is for-warded to the various terminalsin succession.

EWSD

cordless

mobile

fixedA

Global Series Completion Service

Announce-ment unit

IP

VMS

busy

no reply

busy

no reply

53

EWSD SSP services with directand dial-up access

The EWSD SSP services with directand dial-up access are divided into:

• Dial-up Access

• Travel Service

• Automatic Service Selection

• Commercial Freecall Service

Dial-up Access

With Dial-up Access an alternativenetwork operator can enable end-customers of a different networkoperator to access the alternativenetwork by dialing a directory num-ber (with dialed or automaticallyprefixed carrier access code). In thenetwork interworking node (incom-ing gateway) a check is made onthe basis of the directory numberof the calling subscriber (CLI) todetermine whether this subscribermay use the carrier network and itsfeatures.

Features that can be used are:

– Barring of Destinations

– Follow on Calls

– Individual Traffic Restrictions

Travel Service

With the Travel Service, subscribersof an alternative network operatorcan telephone from every tele-phone or PBX from every networkvia the carrier’s network, using aspecial service number and anauthorization code.

In the carrier’s network the sub-scriber can use the features

– Barring of Destinations

– Follow on Calls

– Individual Traffic Restrictions

– Abbreviated Dialing

– Fixed Destination Call

With the feature Barring of Desti-nations, the customer of an alter-native network operator can specifyup to 50 directory numbers forwhich an incoming call can be ei-ther permitted or not permitted. Itis also possible to specify partialdirectory numbers.

With the feature Follow on Calls,the subscriber needs only to dialonce into the network of an alter-native operating company to be ableto make several calls in successionthrough this network.

With the feature Individual TrafficRestrictions, customers of an al-ternative network operator canblock certain destinations (e.g. spe-cific countries) or destination areas(e.g. intercontinental) for their line.

With the feature Abbreviated Dial-ing, the customer of an alternativenetwork operator has the possibil-ity of initiating a call to the desiredsubscriber by dialing an individualabbreviated directory number.

The feature Fixed Destination Callprovides the customer of analternative network operator withthe possibility of setting up a call toa predefined destination by simplylifting the handset; the connectionis made either immediately or aftera predefined delay period. Thefeature is not activated if the callingsubscriber starts to dial anotherdirectory number within the delayperiod.

54

Under a certain directory number,the service Automatic ServiceSelection offers subscribers arange of IN services, from whichthey can select a service usingthe menu and speech-driven in-structions.

With the service CommercialFree Call Service, companiesand advertising agencies can setup calls that are free of charge.The subscriber first hears a pro-motional announcement andthen dials a local directory num-ber to which the connection ismade free of charge.The servicesubscriber decides whether ornot such a call is to be restrictedin time.

EWSD

B

A

Local number

Special code

Promotional announcement

Free Call

Announce-ment unit

Commercial Free Call Service

EWSD

IVPS

Service ①

Service ⑤

A

Announcement unit:

Hello, this is your service provider!

Which service do you want to use?

Dial 1 for service

①

Dial 2 for service

②

Dial 3 for service

③

Dial 4 for service

④

Dial 5 for service

⑤

Automatic Service Selection

IN f

ea

ture

sp

ect

rum EWSD based IN services

Freephone

Reverse Charging

Televoting

EWSD SSP direct accessservices

Global Series CompletionService

Selective Reverse Charging

Time Dependent CallForwarding

EWSD SSP services with directand dial-up access

Barring of Destinations

Follow on Calls

Individual Traffic Restrictions

Abbreviated Dialing

Fixed Destination Call

Automatic Service Selection

Commercial Free Call Service

56

ADMOSSAdvanced Multifunctional OperatorService System

57

The Advanced Multifunctional Op-erator Service System (ADMOSS)is the product developed by Siemensfor integrating "call center” functionsin the EWSD system. "Call center”is the term used to describe acollection of operator-controlledservices at control terminals.

Thanks to its modularity and the lat-est line technology, ADMOSS canbe used for a call center of practi-cally any size and configuration.Thenumber of control terminals can beincreased according to the trafficvolume and the growing range ofservices available; up to 4,095 con-trol terminals can be served by anEWSD network node.

With ADMOSS, the control terminalfunction is performed by the multi-functional switchboards (MSB).TheMSB are connected to EWSD bymeans of ISDN basic accesses, inthe same way as subscribers are.An MSB comprises a standard PCwith Windows NT as the operatingsystem. An MSB is also speciallyequipped with a functionally ex-tended keyboard, an audio adapterand a headset.

The MSB is a classic representationof computer telephony integration(CTI), i.e. it combines informationtechnology and telecommunica-tions. In addition to all the functionsof a modern PC, such as a graphicaluser interface and menu-drivendatabase access, the MSB also hasall the features of modern telecom-munications.

With ADMOSS the operators –known as agents – are hierarchicallyorganized. Up to 9,999 agent IDscan be created, and 4,095 agentscan be active at any one time.

The agent hierarchy consists of:

– 1 to 10 service groups

– per service group,1 to 80 switching groups

– per switching group,1 active chief supervisor

– per switching group,1 to 255 supervisory groups

– per supervisory group,one active supervisor

– per supervisory group, up to256 agents

Thanks to automated functions, theprocessing time required by anagent for individual services is re-duced to a minimum. ADMOSSthereby supports high service qual-ity with a low personnel level.

Automatic call distribution

Automatic call distribution (ACD) di-rects the subscriber requests foragent services to the agent groupsresponsible for dealing with theservices in question. In distributingthe calls, automatic call distribution(ACD) always selects the controlterminal within the group that hasbeen available for the longest time.If no agent in the group is available,the request is placed in a queue.During this time, the calling sub-scriber hears an announcement ora waiting tone.

Automatic call distribution (ACD)can react very flexibly to varioustraffic situations. Up to 16 differentconfigurations can be created fordistributing the different call typesto agent groups. For instance, ser-vice requests can be distributed toa large number of control terminalsduring the day and to a small numberof terminals at night.

Announcements and interactive voice response

The ADMOSS announcements playan important role in unburdeningthe agent of standard tasks and inincreasing the service quality forthe subscriber. ADMOSS uses anEWSD-internal Individual DigitalAnnouncement System (INDAS) forits announcements.

The following announcement func-tions are available:

– Announcement or music whendisconnecting or holding a call

– Announcement while waiting inqueues on a first-in first-outbasis

– Automatic greeting on assign-ment of terminal, plus auto-matic personal greeting

– Service-dependent announce-ments

Speech recognition and DTMFrecognition enable voice-controlledand announcement-prompted dia-log without the intervention of theagent. This unburdens the agentand thereby improves performance.For interactive dialog ADMOSSuses the EWSD-internal IntegratedVoice Processing System (IVPS).

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Traffic assistance

ADMOSS uses the EWSD call pro-cessing functions for traffic assis-tance. The traffic assistancefunctions can be divided into callprocessing functions, call chargefunctions and booking functions.

The call processing functions canbe used to help the subscriber setup calls.

For example, the following featurescan be provided:

– Immediate and practically auto-matic call processing

– Service calls

– Directory number verification

– Outgoing code-11 and code-12 calls

– Trunk offering

– Agent-to-agent calls

– Intercept handling

– Call time restriction

– Large conference with up to25 subscribers

– Call setup after directorynumber inquiry

The call charge function offers ad-ditional services such as:

– Call charge acceptance by athird subscriber

– Collect calls

– Ticket retrieval

– Information on call time andcharges

With the booking function a sub-scriber can book a call up to threemonths in advance. A maximum of60,000 bookings can be stored inEWSD. The following features areavailable:

– Call delay handling

– Appointment booking

– Permanent booking

– Alarm calls: automatic, semi-au-tomatic, by the operator

Directory assistance

The directory assistance (DA) ser-vice offers direct access to nationaland international directory numberdatabases. At the request of a sub-scriber, an agent can quickly andeasily find out the desired directorynumber and forward this to thesubscriber. As a special service, theagent can also, on request, set up acall immediately to the number inquestion.

The most important directory assis-tance functions are:

– Automatic announcement of thedirectory number requested

– Directory assistance followed bycall completion

– Automatic call completion

Special call center features

ADMOSS offers some special fea-tures for call centers:

– Automatic screen-pop-up basedon incoming call

– Outbound dialing, inbounddialing

– Skill-based routing

– Internet access

– Fax, e-mail

– Voice mail

AD

MO

SS

fe

atu

re s

pe

ctru

m Automatic call distribution (ACD)

Announcements and interactivevoice response

Announcement or music whendisconnecting or holding a call

Announcement while waiting in queues on a first-in first-outbasis

Automatic greeting on assign-ment of terminal, plus automaticpersonal greeting

Service-dependent announce-ments

Traffic assistance

Immediate and practically auto-matic call processing

Service calls

Directory number verification

Outgoing code-11 and code-12 calls

Trunk offering

Agent-to-agent calls

Intercept handling

Call time restriction

Large conference with up to25 subscribers

Call setup after directorynumber inquiry

Call charge acceptance by athird subscriber

Collect calls

Ticket retrieval

Information on call time andcharges

Call delay handling

Appointment booking

Permanent booking

Alarm calls: automatic,semi-automatic, by the operator

Directory Assistance

Automatic announcement of thedirectory number requested

Directory assistance followed bycall setup

Automatic call completion

Special call center features

Automatic screen-pop-up basedon incoming call

Outbound dialing, inbounddialing

Skill-based routing

Internet access

Fax, e-mail

Voice mail

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The new generation of telecommu-nications networks makes evengreater demands on the call pro-cessing functions of network nodes:the flow of traffic is constantlygrowing, subscribers are increas-ingly using more than just one ser-vice, the number of gateways isexpanding, and economic consider-ations are calling for optimum uti-lization of network resources.

EWSD meets these demands tothe full extent, proposing powerfulsolutions for all call processingfunctions.

Call processing functions are dividedinto the following groups:

• Call charge registration

• Traffic routing

• Network management

• Traffic data management

• Signaling

• Voice processing

Call charge registration

Call charges are the fees paid forutilization of the telecommunicationsservices offered by an operatingcompany. Call charge registration istherefore one of the most importantbasic functions to be performed bya network node.

In call charge registration, EWSDdifferentiates between:

– Subscriber charges

– Interadministrative charges

– Charges in the intelligentnetwork

– Charges in the SS7 network

Connection charges and charges forthe activation, deactivation and uti-lization of features can be recordedfor each subscriber.

For interadministrative charging,the total amount of traffic is recordedon a time-related basis at the net-work boundaries.

Call charge registration in the intel-ligent network is not related to aparticular line. Each service sub-scriber has a billing number underwhich the charges are added up.

Operating companies can agree onthe SS7 traffic relations amongthemselves. Call charge registra-tion in the SS7 network is dividedinto a component that is related tothe message transfer part (MTP)and one for the signaling connec-tion control part (SCCP). The MTP-related call charge registrationcounts the message signaling unitsreceived by or sent to a signalingpoint.The SCCP-related call charge regis-tration counts the message signalingunits with global title translation(GTT).

EWSDBasic Functions Ensure EfficientOperation

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62

EWSD proposes two differentmethods for the recording of callcharges:

– Periodic pulse metering (PPM)

– Automatic message accounting(AMA)

With the periodic pulse meteringmethod, call charge units areadded up in subscriber-specificmeters. To this end, EWSD gener-ates meter pulses during a call.Each meter pulse corresponds toone call charge unit. The time inter-val in which one or more meterpulses are generated for a call isdetermined by the zoning resultand is calculated on the basis ofthe tariff zone and the tariff itself.

A tariff zone includes all those des-tinations having the same tariffswithin a particular network node.Zoning is based on the followingparameters:

– destination up to 15 dialed digits

– origin 15 subscriber categories,4,047 local area codes per localnetwork node,48 local area codes per transitnetwork node,255 origin codes

– transmission quality speech, low-speed datatransmission,64 kbit/s high-speed datatransmission

The tariff is the unit of measure-ment for the charges incurred inmaking a call.Tariffs can be specifiedin both pulse tariff format as wellas in currency tariff format. Up to512 different tariffs can be created.The time interval can be set be-tween 200 milliseconds and 30minutes, in increments of 4 milli-seconds.

The following items can be speci-fied for each zone:

– 6 tariffs

– 6 weekday categories

– 8 fixed full holidays

– 8 fixed half-holidays

– 8 fixed national holidays

– 16 movable full holidays

– 16 movable national holidays

– up to 96 tariff switchovers perday and zone (in 15-minutesteps)

– up to 1024 tariff change andtariff switchover sequences

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Five charge meters can be freelyassigned for each subscriber. It isthe operating company which de-cides how to assign the meters.For example, charges may berecorded separately for local calls,long-distance calls, the number ofconnections, and the number oftimes features are activated.

The automatic message account-ing (AMA) method stores connec-tion data in a data record for eachindividual call. The connection datamay include, for example, the direc-tory number of the calling and thecalled subscriber, the time at whichthe conversation begins, the callduration, subscriber controlledinput and feature usage. Local au-tomatic message accounting(LAMA) in the local network nodeand centralized automatic mes-sage accounting (CAMA) in thetransit network node record theconnection data. For calculation ofthe charges, the AMA data recordsare transferred to external comput-ing centers. A post-processingprocess then generates individualcustomer bills on the basis of thedata records.

In addition to the basic functions,EWSD also offers a range of otherimportant features for call chargeregistration.

With the feature Charging by Ac-count Code, a subscriber can dialan account code when setting up aconnection. In this way the sub-scriber can differentiate betweenthe charges for outgoing calls madeon a personal, a project-specific ora customer-specific charge account.

The feature Centralized Tariffingtransfers the zoning and the record-ing of connection charges to centrallocations within the network.A tariff determination point isresponsible for the administrationof tariff zones and tariffs as well asfor determining the tariff zone andthe tariff on a call-specific basis.A charge generation point uses thetariff zones and the tariff informationto generate the charges.The charges are recorded in acharge registration point. All chargeinformation is transmitted as SS7messages in the network.With this feature, only very few tariffzone tables and tariff tables needbe administered in the network.This provides for fast and simpletariff switchover and special limitedtariff offers ("happy hours”). Thefeature Centralized Tariffing can alsobe used in the intelligent network.

The feature Flat Rate provides thesubscriber with an unlimited num-ber of calls to certain specific desti-nations for a monthly flat rate.

The feature Hotel Billing transmitscall charge information to a PCbelonging to the subscriber (e.g. ahotel) as soon as the call hasended.

The feature InteradministrativeCharging and Statistics(IACHASTA) provides a flexiblemeans of call charge registration,geared toward administrative de-mands, between operating compa-nies. IACHASTA can use bothperiodic pulse measuring (PPM) aswell as automatic message ac-counting (AMA) for call chargeregistration.

The feature Meter Observation(MOB) is used for monitoring thecharges incurred by individualsubscribers. It is set up on request,whenever a subscriber lodges acomplaint about a bill that was cal-culated on the basis of time-pulsemetering. This feature records thecharge-related connection data forall outgoing and incoming calls.

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Traffic routing

During call setup from the callingsubscriber to the called subscriber,traffic routing evaluates the dialeddigits and works out an availableconnection path. EWSD has somevery powerful routing functions,making optimum use of the avail-able network resources, and there-fore has no problem in coping withlarge volumes of traffic.

Special features provide additionalmeans of routing the call processingtraffic in the network and copingwith the requirements of deregu-lated networks.

In deregulated markets, operatingcompanies must be in a position toidentify their subscribers as con-tractual partners. The means ofidentification is the subscriber’sdirectory number. The featureBlack/ White List can be used toidentify authorized subscribers bymeans of a white list and thosewhich are not authorized via a blacklist.

With the feature Carrier DependentRouting, national and internationalcalls, for example, can be set up viaan alternative network operator inderegulated networks. The sub-scriber selects the desired operat-ing company by means of a carrieraccess code. For calls set up with-out dialing an access code, thelocal network operator can specifytwo standard carriers. The sub-scriber can then change these set-tings by means of subscribercontrolled input.

With the feature Carrier Quota,traffic can be distributed among dif-ferent network operators accordingto a fixed or a dynamic sharing key.The sharing key can be either thetrunk group size of the networkoperator in question, a predefinedpercentage quota or the incomingtraffic volume measured for thecarrier. Up to 20 carriers per desti-nation can be administered.

With the feature Customer Depen-dent Routing, individual calls canbe made via selected networkoperators or selected trunk groupsthat offer, for instance, better trans-mission quality.

The feature Multiple Local Net-works in one Network Node al-lows the subscribers from up to4,047 different local networks to beconnected to one network node viaremote digital line units (DLU). Thismeans, for example, that sub-scribers belonging to a region withanalog network nodes can be pro-vided with ISDN services on aneconomical basis. Such subscribersare then switched physically to theremote ISDN-capable networknode. However, they still remainmembers of their local networkarea.

With the feature Number Portabil-ity, subscribers can keep the samedirectory number when they movehouse within the same local net-work or switch to another operatingcompany. EWSD automaticallyroutes the calls for such subscribersto the right destination. The corre-sponding routing information iscontained in a common database,which is interrogated as a preventivemeasure before each call setup orafter an unsuccessful call setup.This special database is located inone or more EWSD network nodesin a central position in the network.

Business customers owning severalprivate branch exchanges in thenetwork can combine these into asingle direct dial group. The featureOverflow between PBX Groupsincreases the availability and secu-rity of calls made between thePBXs. If an attempt is made to initi-ate a call to a PBX and all directlines are busy or out of order, thereis an automatic overflow to alterna-tive paths via the other PBXs in thesame group.

In order to release traffic paths forcertain subscribers in suddenemergency situations, such sub-scribers can have the operatingcompany assign them certain prior-ities. With the feature PrivilegedTraffic, prioritized subscribers receivespecial treatment. In outgoing traffic,lines can be reserved for suchsubscribers, an unsuccessful callattempt can be repeated or, in caseof a call to a busy subscriber, thecall can wait for the subscriber tobecome available.

The feature Traffic Routing Basedon Transmission Quality makes itpossible to route ISDN traffic to itsdestination only on the transmissionpaths meeting certain quality criteria.The decisive factors in the selectionof a transmission path are the trans-mission medium requirement (TMR)and the ISUP preference indicator(IPI).

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66

Network management

The function of network manage-ment is, in the event of high loadphases or failure of network sections,

– to make sure that the numberof successful, charge-generatingconnections does not dropmore than necessary

– to guarantee the highest possi-ble call setup quality for sub-cribers

EWSD offers a range of powerfulfunctions that ensure optimum uti-lization of the network resources,even in high load phases.

The feature Optimized DynamicRouting (ODR) is used for load-de-pendent traffic routing. ODR auto-matically monitors any instances ofinsufficient or excessive load and,when necessary, regulates suchsituations. This is done by makingoptimum use of all traffic pathsavailable on alternative routes.

The feature Automatic Rerouting(Crank Back) is used when a transitnode cannot find an available trafficpath to a desired destination duringcall setup. In this case, a messageis signaled back to the precedingnetwork node. A new route for theconnection is then searched for inthe preceding network node, via adifferent transit network node.

The feature Automatic CongestionControl (ACC) provides for auto-matic reduction of traffic to a spe-cific overloaded network node. Incase of overload, the network nodeaffected transmits a message tothe adjacent network nodes. Thesethen reduce the traffic there.

The feature Mass Call Control(MCC) is used to detect mass calls.Mass calls to certain destinationscan result from radio or TV quizshows, for example. Since calls tomass-call destinations have a verysmall chance of being switchedthrough, MCC reduces the trafficas close as possible to the origin,thereby granting priority to suc-cessful traffic to other destinations.

With the feature Proportional Bid-ding, traffic to a certain destinationcan be distributed among variousdifferent traffic paths according toa predefined percentage sharingkey. In case of traffic bottlenecksrestricted in time, this feature dy-namically increases the call com-pletion rate.

The feature Call Rate Reduction(Leaky Bucket) makes it possibleto dynamically restrict the traffic tocertain defined destinations. Inhigh load phases, the network canthus be protected from overload.

The feature Call Gapping controlsthe throughput of call attempts tocertain destinations. A time intervalin which only one call attempt ispermitted determines the upperlimit of the maximum number ofcalls. The time intervals that can beset are 0.1 , 0.25, 0.5, 1, 2, 5, 10, 15,30, 60, 120, 300, 600 seconds.

With the feature Trunk Reservation,the operating company has thepossibility of prioritizing certain traf-fic types on selected trunk groups.A number of trunks in the group arereserved for privileged traffic.

Destinations in the network thatare difficult to reach are detectedby means of the feature Hard toReach Control (HTRC). Usually,the reasons behind such situationsare unforeseen events, such as ad-verse weather conditions andearthquakes. In such cases, trafficto the relevant destinations in-creases greatly. A high number ofcall attempts fail because the net-work is interrupted or regionallyoverloaded. To protect the networkfrom unsuccessful traffic, this situa-tion is reduced by HTRC as close aspossible to the origin, therebygiving priority to the successfultraffic to other destinations.

With the feature Code Blocking,the operating company can restrictthe percentage of call attemptsmade to certain destinations. Thelimit can be set between 0 % and100 %, in increments of 12.5 %.

The feature Automatic Alterna-tive Routing is used for optimizingthe search for routes. It is usedwhen no available line can be foundin the direct path during call setup.In such a case, this feature auto-matically reroutes the path searchto the next defined alternativeroute.The overflow to other routingtrunk groups can also be influencedby means of the functions "SKIP","Cancel to" and "Cancel from".

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Traffic data management

The traffic flow in modern commu-nication networks can be guidedoptimally by means of a suitablenetwork organization and load-de-pendent traffic routing. The basisfor the planning of future-orientednetworks is the traffic datarecorded during operation.

For traffic data recording, theEWSD system proposes integratedfunctions that can be operatedwithout any additional equipment.

Traffic measurement registers theevents and status duration of thesystem or sub-systems. Trafficmeasurement can also be startedfor trunks with respect to directionand with respect to certain features.Traffic measurement thereby pro-vides important information for theplanning and operation of the net-work node and the network itself.

Traffic supervision periodicallycompares current traffic data withpredefined threshold values. In thisway, any irregularities in call pro-cessing can be identified at an earlystage, leaving enough time for suit-able countermeasures to be initi-ated. For example, cases of trafficoverload can be recognized in goodtime and intercepted by means ofthe appropriate traffic managementmeasures.

Through subscriber observation,data pertaining to certain individualconnections is recorded. Based onthe data recorded, conclusions canbe made on the quality of servicefor specific connections, on thesubscriber behavior and on the sys-tem and network behavior. In addi-tion, such data can be used todeduce the expected traffic flowand the required resources.

With traffic structure measure-ment, data is recorded on a randombasis from defined measuring ob-jects. The selected measuring ob-jects can be, for instance, the entirenetwork node, all the originatingtraffic, all the incoming traffic, cer-tain subscriber lines or trunks.

Signaling

EWSD can control the traffic fromand to other network nodes with allthe standard signaling systems,such as MFC R1, MFC R2, No. 5and SS7. All signaling systems usedare implemented in accordancewith ITU-T.

In digital networks, the signalingsystem no. 7 (SS7) is predominantlyused. The functions of SS7 areadapted to the needs of digital net-works. The separation of functionsbetween a common message trans-fer part (MTP) and several specificuser parts (UP) results in greaterflexibility.

Message transfer part (MTP)

The message transfer part (MTP) isa user-independent means of trans-porting messages between users.In principle, the message transferpart covers all the basic functionsdefined by ITU-T. In addition tothese it has the following features:

– compatibility with ANSI standards

– option of 24-bit coding of thesignaling codes

The feature High Speed Signal-ing Links (HSL) can be used toeliminate bottlenecks in SS7communication between net-work nodes (e.g. between a sig-naling transfer point and aservice control point in the IN).The Level 3 protocol of the mes-sage transfer part (MTP) doesnot allow more than 16 SS7 linksbetween two network nodes, sothat the maximum possiblebandwidth is 16 times 64 kbit/s.The feature High Speed Signal-ing Links (HSL) offers an SS7link using the maximum trans-mission rate for a PCM30 sys-tem (E1) or a PCM24 system(DS1). The Signaling ATM Adap-tation Layer (SAAL), which wasdefined for broadband networksand is based on ATM cells, isused as the communication pro-tocol for the Level 2 protocol ofthe message transfer part.

The feature Multiple SS7 Net-works expands the range offunctions with respect to networkplanning. With this feature, up to32 SS7 routing domains can beadministrated in a network node.This means that up to 32 operat-ing companies in a communica-tion network can maintain theirown SS7 networks.

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User parts (UP)

Each user part (UP) comprises thecoding, functions and protocols forthe signaling for a particular user.The user parts thereby control e.g.the setting up and tear-down ofuser channel connections, the im-plementation of features, as well asadministrative and maintenancefunctions for the user channels.

Basically, the following user partsare currently used:

– ISDN user part (ISUP)

– Signaling connection controlpart (SCCP)

– Transaction capabilities (TC)

– Operation and maintenanceapplication part (OMAP)

EWSD also supports the IN appli-cation part (INAP) for intelligent net-works (IN), as well as the mobileapplication part (MAP) and thebase station application part(BSSAP) for use in mobile commu-nication systems.

The ISDN user part (ISUP) com-prises the signaling functions forcontrolling connections, for pro-cessing services and features andfor the administration of user chan-nels.The functions comply with therecommendations for ISUP 97 pub-lished by ITU-T in 1997 (corre-sponding to the ISUP Standard,version 3).

The ISUP implemented in EWSD isalso characterized by:

– flexible adaptation to the exist-ing channel-associated signal-ing or to the existing SS7, withthe aid of extended ISUPscreening functions

– proprietary portions for partsnot defined by ITU-T, e.g. forGeoCENTREX, QSIG, charging,etc.

ISUP adaptations for national re-quirements have already been im-plemented for more than 70projects.

The signaling connection controlpart (SCCP) serves to supplementthe message transfer part.

Transaction Capabilities (TC)support the exchange of messagesbetween users without any refer-ence to a user channel connection.

SCCP and TC contain all the majorfunctions defined by ITU-T.

The Operations and Mainte-nance Application Part (OMAP)contains functions for measure-ment and supervision of the SS7network. For example, as part ofthe measurements defined for SS7,information on the load on the SS7network is output at regular inter-vals (5, 15 minutes). These mea-surements can be started asrequired. The “first and interval”measurements only provide an in-formation output if a specific eventhas occurred and this event recursin the measurement interval (e.g.rejection of messages because of arouting error). “On occurrence”measurements are used to reportall critical events immediately tothe operator.

The feature MTP route verifica-tion test (MRVT) is an SS7management function. Using thisfeature, the routing of the signal-ing traffic between an originat-ing point and a destination pointin the SS7 network can betested. This test encompassesall relevant routing tables be-tween the originating point andthe destination point of a signal-ing connection.

The feature SS7 Accounting isused for call charge registrationfor SS7 traffic between differentoperating companies.

In deregulated networks, oper-ating companies may agreeupon SS7 traffic relations amongthemselves. The feature SS7Screening ensures that only theagreed traffic can be processed.Traffic not included in the agree-ment is prevented and reportedto the operating company.

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71

Voice processing

Announcements are playing anever increasing role in telecommu-nications today. They improve theservice and user-friendliness in callprocessing and, in conjunction withdialog-driven functions, have becomeindispensable.

With its individual digital announce-ment system (INDAS), EWSD of-fers a powerful functional packagewith which suitable announce-ments can be independently com-posed in an easy and flexiblemanner.

In addition to the announcementsystem, EWSD also offers with theintegrated voice processing system(IVPS) a speech-based solution forinteractive dialog between the sub-scriber and the system.

A wide range of possible applica-tions exists for speech-based dialog,such as:

– Dialog support for subscriberfeatures

– Call completion after directoryinquiries

– Automatic feature subscription

– Automatic provision of operatorservices

– Speech-menu-driven selectionof operator groups (automaticoperator selection)

Individual Digital AnnouncementSystem (INDAS)

The individual digital announce-ment system (INDAS) consists of:

– three software programs:PC-CAPE,ALINA,OCANEQ service software

– OCANEQ module

A normal PC is used to design andcontrol the announcements usingthe software programs PC-CAPE,ALINA and OCANEQ service soft-ware. The three software programscan also be run separately on dif-ferent PCs.

PC-CAPE (Cutting and Program-ming Equipment) is a versatile andefficient program for the productionand modification of announce-ments. The PC on which it runsmust be equipped with a micro-phone, a sound card and head-phones or active loudspeakers.

ALINA (Administration of Languagedata for Individual Announcements)is used for the administration of theannouncements.

OCANEQ Service Software is usedfor loading the speech data into theOCANEQ module.

The OCANEQ Service PC is a PCor notebook with Windows NT 4.0which contains at least theOCANEQ service software.

OCANEQ (Operationally ControlledEquipment for Announcement) isthe announcement system hard-ware in the EWSD switch.OCANEQ is a module installed inan LTG (line/trunk group).

Integrated Voice ProcessingSystem (IVPS)

The integrated voice processingsystem (IVPS) is based on the userinteraction LTG (UI-LTG). Each UI-LTG can perform 31 dialogs at anyone time. Several UI-LTGs can beused in parallel in EWSD.

The UI-LTG contains for IVPS:

– SCR hardware module

– OCANEQ hardware module

The module SCR (speech recogni-tion and code receiver) simultane-ously supports the recognition ofspeech inputs and dual-tone multi-frequency signals. Speech recogni-tion is implemented on the moduleas additional software that can beloaded.

The module OCANEQ is also usedin IVPS as an announcement device.

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EWSDAdditional Functions Expand the Rangeof Applications

EWSD expands the range of appli-cations for telecommunication ser-vices with additional functions.

QSIG

EWSD supports the interaction ofprivate communication networks andprivate branch exchanges at differ-ent locations and in corporate net-works over the PSTN. Here, EWSDtakes on the role of a backbone net-work node. Private networks andPBXs can be connected to thisEWSD backbone either directly orby means of a HICOM accessnode. The principal use of theHICOM access node is for trafficrouting and conversion of QSIG andother network protocols (e.g. Cor-Net-N and DSS1).

The signaling information betweenthe private network or the HICOMaccess node and EWSD is trans-ported via QSIG. This is a standard-ized signaling system (referencepoint Q) for ISDN-based signalingbetween private communicationnetworks and PBXs. QSIG ensurestransparent transportation of thecontrol information during featureusage. EWSD transports the signal-ing information in the PSTN asISUP messages in the case of circuit-related connections. In the case ofnon-circuit-related connections, thesignaling information is transportedby means of TCAP. QSIG is alsoused for the network-wide func-tions of GeoCENTREX.

The following features can be of-fered throughout the network onthe basis of QSIG:

Bearer services




– Packet Mode, SemipermanentB Channel Access

– Packet Mode, B Channel Access

– Packet Mode,Switched B Channel Access

Teleservices



– Teletex


– Videotex

– Videotelephony

Subscriber features

– Call Completion to BusySubscriber (CCBS)

– Call Completion on no Reply (CCNR)

– Call Hold (CH)

– Calling Line IdentificationPresentation (CLIP)

– Calling Line IdentificationRestriction (CLIR)

– Connected Line IdentificationPresentation (COLP)

– Connected Line IdentificationRestriction (COLR)

– Call Forwarding (CF)

– Call Waiting (CW)

– Direct Dialing In (DDI)

– Multiple Subscriber Number(MSN)

– Subaddressing (SUBA)

– Terminal Portability (TP)

GeoCENTREX features

– Calling Name Identification Pre-sentation (CNIP)

– Calling Name Identification Restriction (CNIR)

– Connected Name IdentificationPresentation (CONP)

– Connected Name IdentificationRestriction (CONR)

Cordless telephone mobility(CTM)

The cordless telephon mobility(CTM) service enables the sub-scriber to move freely within thegeographical region of the corre-sponding network node. To avail ofthis service, the subscriber needs aDECT-standard terminal (DECT =digital European cordless tele-phone) or a suitable dual-mode mo-bile telephone (GSM and DECTstandard).

The mobile link to the subscriber iscreated in a CTM region by radiobase stations (RBS). In turn, a num-ber of radio base stations are con-nected to a radio distribution unit(RDU). An RDU is connected toEWSD by means of a V5.1 or V5.2interface.

Handover is possible within anRDU region.

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74

EWSCountryCost-Efficient Call Processing forRural Areas

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The organization of telecommuni-cations networks in rural areasposes a particular problem for net-work operators. On the one hand,subscribers there demand thesame range of functions madeavailable to subscribers in moredensely populated areas. On theother hand, however, traffic densityis low and, in many cases, is notsufficient to support economicallyviable operation of the line networkand network nodes.

EWSCountry offers several solu-tions to ensure that, while main-taining low investment costs,subscribers in rural areas can stillbe provided with all the functionsand features of a modern telecom-munications network.

Remote shelter DLU (RSDLU)

The remote shelter DLU (RSDLU)integrates the complete range oftelecommunications equipmentthat is required to incorporate into acommunications network thosegroups of subscribers located farfrom the central EWSD networknodes. With RSDLU variants for150, 400 and 700 subscribers, thenetwork operator has the greatestpossible flexibility in setting up andexpanding its access network.

The RSDLU is equally suited foroperation within a building or in theopen air.The connection to the net-work node or between RSDLUsuses the following:

– PDH technology: State-of-the-art optical fibertechnology with 2 x 2 Mbit/sand 34 Mbit/s.Existing 2-wire technology withHDSL

– SDH technology: State-of-the-art optical fibertechnology with 155 Mbit/s or622 Mbit/s

Optical fiber distributedconcentrator (OFDC)

The optical fiber distributed con-centrator (OFDC) represents cost-efficient line technology forsubscribers in areas that are partic-ularly sparsely populated. OFDCuses the latest optical fiber tech-nology for the line.

Via an optical fiber ring of up to1,000 km in length, up to 848 sub-scribers can be connected.

The interface to the optical fiber issituated in a DLU. The connectionpoints in the optical fiber ring formremote terminals (RT). Each remoteterminal can be used to connect upto 80 analog or 64 digital sub-scribers. In parallel with the sub-scribers, up to four PCM30 linkscan be connected. These PCM30links can be used for connecting toother DLUs, for example. Apartfrom line technology, the remoteterminals also contain the equip-ment for refreshing the signaling onthe optical fiber ring.

Compact digital exchanges (CDE)

The compact digital exchange(CDE) is a physically compressedform of an EWSD network node.Depending on the capacity stage,up to 15,000 subscribers or up to3,700 trunks can be connected to aCDE.

A CDE offers the same range offunctions as a regular EWSD net-work node. Owing to its smallersize, a CDE is particularly suited forcontainer installation.

Small digital exchange (SDE)

The small digital exchange (SDE) isa small but fully independentEWSD-compatible network nodethat can be used cost-efficientlywith as few as 100 subscribers(analog or digital). The SDE is suit-able for implementation of localnetwork nodes and transit networknodes (for up to 960 trunks) as wellas combined local/transit networknodes.

As far as its technical design is con-cerned, the SDE basically consistsof components from the digital lineunit (DLU) in the EWSD system.This means that, by simply replacingcertain modules, the SDE can beexpanded at any time into a DLUwith the full range of EWSD fea-tures. Thus, as demand increases,the bulk of the original investmentcan be used again in setting up anEWSD network node.

The SDE exists in three basic con-figurations:

– Cabinet for up to 280 subscribers(switching part only)

– Cabinet for up to 280 subscribers(switching part, MDF, O&M-PC,rectifier, batteries)

– Cabinets for up to 3,400 sub-scribers (switching part only)

The SDE can be housed in contain-ers. It therefore takes very littletime to set it up temporarily, evenin areas with an underdevelopedinfrastructure.

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EWSD HardwarePowerful, Versatile and Flexible

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EWSD performs all its functions ona single hardware platform. Thehardware components are notedfor their high static efficiency and ahigh dynamic loading capacity. To-gether, they ensure the exceptionaldegree of reliability provided by theEWSD system.

The EWSD hardware is based onthe latest technology such as appli-cation-specific integrated circuits(ASIC), large-scale integrated (LSI)telecom chips and digital signalprocessors (DSP). In addition,through further technological devel-opment, the EWSD structure nowtakes up a lot less space.

Greater efficiency in the centralsystem areas

The following components makeup the central system area:

– Switching network (SN)

– Coordination processor (CP)

– Message buffer (MB)

– Central clock generator (CCG)

– Multi Service Platform (MSP)inklusive Signaling systemnetwork control (SSNC)

The switching network (SN) formsthe heart of the network node.Thisis where the connections betweenorigins and the desired destinationsare created. Through the introduc-tion of the new switching networkD (SND), typical characteristic val-ues have now been quadrupled.

With a traffic load of 100,000 erlang,240,000 connectable ports and2,016 LTG ports, the system nowoffers the greatest through-con-necting capacity.

The new switching network stillonly comprises a handful of mod-ules. It is structured in a singlestage and free from blocking. Thismeans that n x 64 kbit/s functionsare also possible with no restric-tions. Internally, the SN uses opticalfibers for setting up connections.

The interfaces to existing line/trunkgroups (LTG) are fully supported bythe new switching network.

The coordination processor (CP)is the efficient partner of decent-ralized controls in the periphery. Asa multiprocessor, the CP can beadapted to any performance re-quirement. In its maximum capac-ity stage, the CP displays adynamic capacity for approximately4 million busy hour call attempts(BHCA).

The coordination processor (CP)thereby forms the OA&M interfaceof EWSD. The EWSD NetManager(ENM) is available for local, remoteor centralized operation. In additionto the X.25 interfaces currentlyavailable in EWSD for OA&M, theEWSD PowerNode now also hasaccess to a more efficient LAN in-terface.This can be used to processfile transfers at a much faster rateof 10 Mbit/s, e.g. for call chargedata and traffic measurement data.

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The message buffer (MB) servesto coordinate the exchange of mes-sages within the network nodebetween the CP, the SN, the SSNCand the LTGs. The new messagebuffer D (MBD) has an ATM-basedcommunications bypass to theSSNC.The EWSD PowerNode thusapplies ATM technology internallyand benefits by the associatedadvantages in terms of speed. Inthis way, the message buffer re-lieves the CP and contributes to itshigh performance.

The central clock generator (CCG)is in charge of synchronizing thenetwork node and, if necessary, thenetwork itself.The CCG operates ata very high degree of precision andmay additionally be synchronizedby means of an external masterclock.

The Multi Service Platform (MSP)forms the central part of the EWSDinnovation architecture. The MSPprocesses:

– SS7 signaling for narrowbandapplications in the EWSDPowerNode

– Routing of Internet traffic in theEWSD Internode

– SS7 signaling for broadband ap-plications in the EWSDBroadbandNode

– Switching of ATM traffic in theEWSD BroadbandNode

– OA&M tasks for reducing theload on the coordinationprocessor

In the EWSD PowerNode thefunction of the Signaling SystemNetwork Control (SSNC) is imple-mented on the basis of the MSP.The SSNC is the high-performanceEWSD subsystem for SS7 signalingvia the message transfer part(MTP) and the signaling connectioncontrol part (SCCP). The SSNC isof scalable design; it can operateup to 1500 SS7 signaling links, andit processes more than 100,000message signal units per second(MSU/s) as well as more than 4000SCCP global title translations persecond (GTT/s).

The SSNC can be used in all imag-inable SS7 network applications,e.g. as:

– Signaling end point (SEP)

– Stand-alone signaling transferpoint (STP)

– Integrated SEP/STP

– SCCP Relay

A further possibility is its use as agateway between different net-works, network operators or net-work topologies, such as ITU-T14 bit and ITU-T 24 bit ANSI. Forthis application the SSNC offersfeatures for recording and account-ing traffic with adjacent networksas well as for screening. It is alsopossible to separate the networkinto a maximum of 32 individualnetworks. This is implementedwithin the EWSD system, it is com-pletely transparent and complieswith the standards.

With the SSNC, up to 4096 routesto other SS7 signaling points canbe set up. With the SSNC it is pos-sible to connect:

– SS7 links with 64 kbit/s

– SS7 high-speed links with 2 Mbit/s or 1.5 Mbit/s (E1/DS1 PCM links)

– Broadband links in ATM technology with n x 64 kbit/s or n x 56 kbit/s

As a future-proof system the SSNCalso supports the interaction ofnarrowband and broadband signal-ing on MTP and SCCP level as wellas a maximum message length of 4 kbyte on broadband links.

Greater efficiency and new func-tions in the system periphery

The following components makeup the system periphery:

– Digital line units (DLU)

– Line/trunk groups (LTG)

– Integrated Point of Presence(IPoP) / Packet Hub (PHUB)

– Remote switching unit (RSU)

The current changes in the world oftelecommunications are primarilyaffecting the subscriber line sector.Correspondingly, the goal behindEWSD innovation was also tostrengthen the performance of thesystem periphery to a substantialextent and to integrate new func-tions.

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The digital line units (DLU) con-centrate the traffic from subscribersto the EWSD. They either form anintegral part of the network node orare implemented remotely in prox-imity to the subscriber groups.

An important feature of the remoteDLU is the emergency service. Inthe event of a breakdown of thesignaling channels to the control-ling EWSD network node, theemergency service allows the sub-scribers connected to the DLU(analog, ISDN, GeoCENTREX) tocontinue telephoning.

With the new digital line unit G(DLUG), subscriber lines can nowbe provided at an even more eco-nomical rate than before. Thanks tothe progress made in integrationdensity in semiconductor technol-ogy, extension modules for up to32 subscribers are now possiblefor the very first time. This meansthat one DLU can be used for 2,000subscriber lines.

The following items can be con-nected to the DLU:

– analog subscriber lines (POTS)

– ISDN basic accesses (ISDN-BA)

– high bit-rate subscriber lines upto 2 Mbit/s

– V5.1 interface

High bit-rate subscriber lines of upto 2 Mbit/s connected to the DLUare used for Internet access. Spe-cial extension modules are avail-able for this purpose:

– universal asymmetrical digitalsubscriber line (UDSL)

– symmetrical digital subscriberline (SDSL)

Access networks from other sys-tems can be connected to the V5.1interface.

The DLUG takes account of the in-creased mean traffic density persubscriber through a fourfold in-crease in the transport capacity tothe LTGs: 16 PCM30 systemstransport traffic of up to 390 erlang.The DLUG is connected to fourLTGs.

For the port area, the line/trunkgroups (LTG) form the interface tothe switching network. All linetypes can be connected to theLTGs, and all signaling proceduresused on the lines can be processedby the LTGs.

One LTG can be used for connecting:

– up to four primary digital carriers(PDC) at transmission rates of2,048 kbit/s (for trunks, remoteDLU or primary rate access)

– up to two primary digital carriersat transmission rates of4,096 kbit/s (for local DLU)

– access network via a V5.2 interface (for up to four V5links)

For Internet access, EWSD hasan Integrated Point-of-Presence(IPoP). The IPoP offers all the basicfunctions of a remote Internet ac-cess server, such as

– dial-up access to the Internet,intranets or virtual private net-works (VPN) for analog andISDN subscribers, and

– voice packaging in accordancewith the Voice-over-Internetstandard.

The IPoP is connected to an LTGlike a DLU.

The Packet Hub (PHUB) is likewisepart of the DLU. It guides the highbit-rate Internet data traffic fromthe subscriber access to the Inter-net.The packet hub can also performa remote access server function(RAS) for the Internet ServiceProvider (ISP).

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The remote switching unit (RSU)occupies a very important positionwithin the framework of EWSD in-novation. In the consolidation of tra-ditional networks as well as theconstruction of new networks, theRSU can take the place of smallnetwork nodes, DLU clusters or re-mote control units (RCU). Up to50,000 subscribers can be con-nected to an RSU. Internal traffic isthrough-connected directly in theRSU. This reduces the load on thetransmission equipment to the con-trolling EWSD network node. As aresult, the transmission paths canbe dimensioned in a cost-effectivemanner.

In the event of a breakdown of thesignaling channels to the control-ling EWSD network node, the RSUhas an emergency service function.While the emergency service is inoperation the connected sub-scribers still have access to a lim-ited range of EWSD.

Like an EWSD network node, theRSU also offers the entire range ofline interfaces:

– analog subscriber lines (POTS)

– ISDN basic access (ISDN-BA)

– ISDN primary rate access (ISDN-PA)

– high bit-rate lines (UDSL, SDSL)

– 2 Mbit/s leased line

– Internet access

– V5.1 interface

– V5.2 interface.

An RSU is made up of DLU, LTGand remote timeslot interchange(RTI). Of these, the RTI is the onlynew hardware development, i.e.the DLUs and LTGs already in usein the network node can be used inan RSU. Small EWSD networknodes, DLU clusters and remotecontrol units (RCU) can thereby beeasily converted into RSUs withthe same hardware. Even remoteDLUs can be directly connected tothe RSU.

Interface trunks connect the RSUvia the RTI to the controlling EWSDnetwork node. For connection ofthe interface trunks the EWSD net-work node uses the host timeslotinterchange (HTI). All data for callprocessing, charging and theOA&M is exchanged over signalingchannels of the interface trunks.Sidedoor trunks connect neighbor-ing RSUs and enable traffic routingwithout affecting the transmissionequipment to the controlling EWSDnetwork node. Backdoor trunks aretrunks with SS7 or channel-associ-ated signaling. They make the con-nection from the RSU to othernetwork nodes.

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EWSD SoftwareIntelligence for Every Application

The EWSD software is based on amodular design. This means it caneasily be adapted to suit the spe-cific needs of each operating com-pany. It also means that newfunctions and features can be easilyincorporated into the EWSD soft-ware.

The EWSD software is written in theprogramming languages CHILL, C++and Assembler.

Software principles

The EWSD software, like theEWSD system in general, is subjectto the highest degree of qualitycriteria.

Reliability – The reliability of theEWSD software is based upon its:

– practical accuracy, completeness,function performance

– consistency, integrity, errorprevention

– fail-safety, minimum spread oferror

– resistance to overload

Flexibility – The flexibility of theEWSD software is evidencedthrough its:

– operator-specific configurability

– system expansion during opera-tion

Portability – The portability of theEWSD software is ensured throughcompilers that generate the programcode for various different targetcomputers.

User-friendliness – Operation ofthe EWSD software requires verylittle effort. The user-friendliness ofthe EWSD software is ensuredthrough its:

– easy-to-learn operating language

– wide range of menu-drivenoperations

– interactive operation manuals

– resistance to incorrect operation

– operator control possibilities forcertain system processes

Ease of maintenance – The EWSDsoftware supports the detectionand correction of errors throughthe:

– ease of performing minor soft-ware modifications

– modularity, optimized structureand transparency

– ease of testing

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Efficiency – Efficiency within theEWSD software is achieved throughthe:

– implementation of compilers togenerate a program code that is optimized for the operator’sapplication program system

– use of measuring instrumentsto determine how often a pro-gram is called in within a partic-ular processing sequence andlow long its runtime is

– use of certain algorithms tosolve specific tasks

– use of the programming languageAssembler in tasks with a criticalexecution time

– program optimization by adaptingprogram flow to the frequentlyoccurring standard cases

– subdivision of complex tasksinto sub-tasks that can beexecuted in parallel, indepen-dently of each other, starting ata specific processing time

– distribution of the tasks occurringover various processors

– privileging certain processes, sothey can run, in part, withoutinterruption

– assigning urgent processes ahigher priority, so they can beexecuted before other processesof a lower priority.

Quality control – Quality controlsare performed at all stages of soft-ware development. On completionof each stage in development,tests are performed to check thatthe results attained meet the de-fined requirements and fulfill thespecified quality standards. Onlyafter such quality controls havebeen performed is the result re-leased for use as a basis in furtherdevelopments.

The quality control measures areimplemented on the basis of a chainreaction.The results obtained in thesoftware development stages de-pend on each other with respect toquality, i.e. the final quality of onestage is the starting quality for thenext stage.

The quality of analysis can be seenas the basis. This affects the entiredevelopment process, in particularthe quality of design and of imple-mentation. Detailed, planned codereviews are just as important forquality assurance as the extensivetest phase. System release is sub-ject to strict quality criteria.

Software architecture

The flexibility of the EWSD softwareis based upon the extensive use oftransient software. Together withthe node-specific database, thisforms the application program sys-tem (APS). Only certain processors,such as the control within theswitching network (SN), the controlwithin the message buffer (MB),and the subscriber and trunk mod-ules, actually contain firmware pro-grams.

Just as the hardware is divided intosubsystems with decentralizedcontrol, the EWSD software is alsodivided according to function. Thismeans that the simpler functions tobe performed more frequently aredealt with by the system peripherycontrols. The more general andcomplex functions are executed bythe coordination processor (CP).

Each processor within EWSD hasits own operating system. Thescope of each operating systemdepends on the tasks to be han-dled and the resources to bemanaged by the processor. Alloperating systems perform theirtasks under real-time conditions.

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Database

EWSD operation requires a largevolume of data.This data makes upthe EWSD database, which formspart of the application software ofthe network node.

The database is characterized bythe following features:

– rapid data access for call setupand clear-down within a shortperiod of time

– data integrity and data consis-tency, to minimize the possibilityof data errors

– optimum use of data memorycapacity by using redundantdata only where it is technicallyrelevant

– expandable data structures, sothe database can be easilyadapted to expansions of thenetwork node

Access to the database is only pos-sible by means of special accessprocedures at certain defined inter-faces. The application programsremain unaware of the manner inwhich the data is stored within thedatabase (information hiding). Theadvantage of this is that the appli-cation programs remain unaffectedby changes in data organization.

The database is administered cen-trally in the coordination processor(CP). In addition, copies of certaindata are also available in theline/trunk groups (LTG) and in thedigital line units (DLU). The signal-ing system network control (SSNC)contains a database independentof the CP. For security reasons, theentire database (CP and SSNC) ismapped to magnetic disk.

The database contains semiperma-nent data as well as transient data.

Semipermanent data describesthe static capacity of the networknode. It includes, e.g. the sub-scriber data, line data, routing andzoning data or data for system con-figuration.

Semipermanent data is subject tostrict security requirements, as anydata errors in the switchingprocess would produce undesiredresults. A wide range of measuresare taken to protect the semiper-manent data, i.e.:

– semipermanent data lies in pro-tected memory sectors

– data access is only possible bymeans of specific coordinatedaccess procedures

– the semipermanent data isadministered centrally

– personal and device-specificpasswords are required formodifications

– all access is controlled bymeans of an authorization test

– all changes made to the data-base are recorded

– the distributed data is subject toan ongoing consistency check

Application programs have read-only access to semipermanentdata. If necessary, however, the op-erator can modify the semiperma-nent data. Certain types of data canalso be modified by means of sub-scriber-controlled input (e.g. cre-ation of call forwarding).

Transient data describes the cur-rent status of the network nodeand the call-processing activities. Itincludes, e.g. information on theoperating status of the hardware,the status of calls and the availabil-ity of resources. It also contains theresults of call-processing activities(e.g. call charge data, traffic mea-surement data). Transient data isnot write-protected; it is read andmodified chiefly by the call-pro-cessing programs.

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Recovery

The EWSD software is providedwith safeguarding devices that en-sure the system’s availability andperformance level. The recoveryfunction comprises all the measuresrequired for operation of the systemor for reestablishment of fault-freeoperation following malfunction.The recovery function includes:

Installation recovery – this is per-formed to start operation of thesystem. It incorporates startup ac-tions for initial operation of a newnetwork node as well as startupactions for the implementation of anew version of the application pro-gram system (APS) in an existingnetwork node.

Central recovery – this comprisesthe startup actions used to neutral-ize a malfunction of the coordina-tion processor during operation andthereby reestablish the perfor-mance level of switching operation.

Recovery in the call-processingperipherals – this is used to neu-tralize a malfunction in a peripheralsubsystem and to make the sub-system in question available onceagain to the coordination processor.

The choice of recovery level de-pends on the type and frequency ofthe malfunction occurring. By se-lecting the right recovery level, thesystem can be quickly returned tofull performance without any effecton call processing. However, incase that the selected recoverylevel cannot fully eliminate the mal-function, the safeguarding programsinitiate the next highest recoverylevel.

Overload handling

Bottlenecks in the available networkcapacity lead to an ever decreasingswitching performance. As a result,many call requests are left un-processed.

If the load exceeds a certain prede-fined limit, the overload handlingfunction of EWSD comes into action.

The aim of overload handling is, attimes of high load or overload, toreserve switching capacity for callsthat are likely to be successful andso ensure that any loss of chargesis reduced to a minimum.

Overload handling comprises a rangeof control mechanisms. These re-duce the load on the processorswithin the line/trunk groups and onthe coordination processor, sothese can use their control capacityfor meeting call requests with avail-able lines.

Existing connections are not affectedby overload handling.

Software upgrade

New features in EWSD are madeavailable in the form of a new versionof the application program system(APS). Using the OSU function(optimized software upgrade), theAPS can be changed with a maxi-mum system downtime of approx.one minute.

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EWSD Operation and MaintenanceEfficiency at an Optimized Cost

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Modern communication networksare making ever-increasing de-mands on operation and mainte-nance. This is due to variouschanges that can be observed inthe marketplace.

The primary cause is the transitionfrom monopoly markets to deregu-lated markets. This has intensifiedthe competition for network opera-tors, who are now adapting theiroperating procedures to the changedconditions:

– by optimizing their O&Mprocesses, starting with the im-provement of customer serviceright through to a drastic reduc-tion of the expenditure for man-agement activities in thenetwork nodes

– by speeding up the processingof their business

– by cutting down the "time tomarket" when introducing newfeatures

– by modernizing customer ser-vices, e.g. by ordering and con-figuring products and servicesvia the Internet

The networks are also subject to acontinuous process of evolution, inthe course of which the telephonenetwork and the data networks aregrowing closer and closer together.Broadband data transmission usingATM technology is becoming in-creasingly important.

Network operators are thereforeconcentrating on O&M solutionsthat satisfy the changed require-ments and secure their companiesa competitive edge in the market-place.

EWSD NetManager

The EWSD NetManager (EMN) isthe efficient, cost-optimized man-agement system for EWSD. It of-fers a complete range of facilitiesfor performing all operating, admin-istration and maintenance func-tions on EWSD network nodes andin EWSD networks. All operatingprocedures of the EWSD NetMan-ager are tailored to EWSD. EWSDand EWSD NetManager interoper-ate via function-oriented propri-etary interfaces and also viastandard interfaces.

The EWSD NetManager guaran-tees low operating costs thanks tolarge-scale automation, easy execu-tion even of complex operatingtasks, and optimum resource man-agement. Using interfaces basedon the World Wide Web (WWW) itis also possible to operate theEWSD entirely via a Web browser.

Integration and coexistence

The EWSD NetManager can quiteeasily be integrated into any exist-ing office environment.

The EWSD NetManager uses theWindows NT operating system,which is used all over the world.The graphical user interface and allthe standard Windows NT func-tions are also available on theEWSD NetManager. This means areduction in training costs, becauseevery user with PC experience isimmediately working in a familiarenvironment.

On a craft terminal (CT) it is possi-ble to use Office applications (e.g.text editing, E-mail) as well as per-forming all EWSD operating func-tions. It is also possible to use awide range of other commercial(Windows NT) software productson the craft terminal.

The WWW-based interfaces offeraccess to the graphical user inter-face (GUI) of the EWSD NetMan-ager, irrespective of the basichardware and software of the oper-ator workstation (e.g. Windows NT,Windows 9x, MacIntosh, X-Terminal).

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Thanks to its modern Java interfacetechnology, the EWSD NetManageris also easy to integrate into complexexisting management systems. Anew version of the EWSD NetMan-ager can be phased in. Coexistencewith previous versions or with olderEWSD management systems (e.g.Operation and Maintenance Termi-nal, data communication proces-sor) is guaranteed, especiallycoexistence of the Unix-based ver-sions of the EWSD NetManager(Node Commander) and the newNT-based version. By adding NTservers and by upgrading the clientsoftware it is possible to obtain astate-of-the-art EWSD NetManager.

In such a case, the operator is un-aware of whether the function se-lected on the client terminal isrunning on the Unix server or theWindows NT server.

The Windows NT-based EWSDNetManager is a prerequisite for in-troducing EWSD Innovation in thenetwork. It contains the completeIT infrastructure for Q3 and SNMPinterfaces. It is also possible to usecomplete solutions for automationapplications.

EWSD services and features

EWSD offers a comprehensiverange of services and features. TheEWSD NetManager fully supportsthe entire spectrum of EWSD ser-vices and features. The immediateavailability of the EWSD servicesand features is guaranteed at alltimes by the appropriate version ofthe EWSD NetManager. FutureEWSD versions will also automati-cally be provided with the optimaloperating and maintenance func-tions by means of synchronizedEWSD NetManager versions.

EWSD Innovation

The EWSD NetManager guaranteesfull operability of the innovationplatform EWSD PowerNode andthe innovation applications EWSDInterNode and EWSD Broad-bandNode. In this way the EWSDNetManager supports the evolutionof the networks and the introduc-tion of new services.

Scalability

Scalability enables the EWSD Net-Manager to keep in step with theexpansion of the network and thechanging requirements of the oper-ator. In its minimum configurationthe EWSD NetManager consists ofone or more craft terminals (CT),which can be connected to anEWSD network node as a local orremote unit.The craft terminals canbe combined into work groups. In aclient/server architecture theEWSD NetManager can performthe O&M tasks for several millionEWSD ports from a central location.

Regardless of the configuration,the user interface is always thesame for identical operationaltasks, and the existing hardwarecan be used again.

The standard equipment of everyEWSD network node also includesthe CT/BOOT, a special version ofthe craft terminal. CT/BOOT pro-vides all the functions required forputting the system into operationand for performing maintenancetasks on site.

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Centralization

The EWSD NetManager is optimizedfor centralized operation of EWSDnetworks.This includes various func-tions.

Performing parallel managementactivities in several EWSD networknodes includes:

– Coordination of operating,administration and maintenancetasks depending on the taskarea, user, user groups, userrights

– Administration of access rightsand passwords and updating inall EWSD network nodes

Processing of information fromseveral EWSD network nodes in-cludes:

– Reception and distribution ofinformation according to user,user groups, applications

– Support of user- and task-orientedprocesses

– Supervision of EWSD networknodes

– Forwarding of alarms and mes-sages to users, user groups andapplications

– Centralized provision of ser-vices, logging, etc.

Administration of the managementcenter includes:

– Administration of workstations

– Administration of users, usergroups, user rights

– Night concentration

The security concept for centralizedoperation is implemented in accor-dance with DoD C2.

Customer-oriented user interface

The EWSD NetManager offers con-siderable scope for performing O&Mtasks.The user interface on the craftterminal can be adapted according tospecific requirements.

User-friendly input on the craft ter-minal is supported by:

– Command sequences that canbe designed with graphical aids

– Predefined, customer-orientedcommand files and profile tech-niques

– Interactive help

– Electronically available userdocumentation with interactiveoperating and maintenanceprocedures

Automation

To supplement the user-friendlybasic functions, the EWSD NetMan-ager has applications for automationand improvement of efficiency inthe service management and net-work management areas.

The applications can be used op-tionally on the EWSD NetManager.Each one represents a completesolution for the special require-ments and problems of individualcustomers.

The following applications are avail-able for Service Management:

• Subscriber ProvisioningBy means of improved subscriberadministration it is possible, forexample, to install a service inthe network or network node assoon as an order is placed and tomake the service available to thecustomer immediately.The appli-cation supports the operator bydefining feature packages and byautomatically selecting and allo-cating a free line.

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• Subscriber Complaint SystemThis application shortens the re-sponse time in cases of enqui-ries or trouble reports from theend customer. It helps to increasethe customer’s satisfaction withthe network operator. Amongother things, the operator has ac-cess to all subscriber data, whichmeans that an operator proces-sing a report can immediatelycall up the subscriber’s statusand perform line tests. Thismakes it easier to coordinate anyrepairs.

• GeoCENTREX ManagementThis application offers supportfor the network-wide executionof GeoCENTREX administrationtasks. Complex tasks can bedealt with more efficiently:Administration of GeoCENTREXgroups: (numbering plans, callcharge registration, subscriberadministration, PBXs, huntinggroups)

Administration of attendant func-tions: (attendants, attendantgroups, multi-functional attendantconsole, call distribution)

• BillingThis application provides a com-plete solution for billing with endcustomers and between networkoperators.The application is based on AMAand IACHASTA, the billing me-thods used in EWSD.The call datarecorded by these methods(date and time of the call, call du-ration, etc.) is collected automa-tically from the EWSD networknodes at regular intervals. If ne-cessary, the call data can also becollected manually .Billing is based on the call dataand on additional informationsuch as membership of particularcustomer groups and the validtariff.The bill can contain a breakdownof call charges, standing chargesand special charges (e.g. for re-pairs).The application permits flexibleallocation of tariffs, e.g. for speci-fic customer groups. Likewise,special short-term tariffs (happyhour), for example, can be set upwithout any great effort.

The following applications are pro-vided for Network Management:• Call Routing

Call Routing is used for configu-ration and control of the trunknetwork. The application providesthe operator with a graphicaluser interface that is tailored tothe necessary operating proce-dures – instead of individualcommands. The interdependen-cies with the SS7 network arealso taken into consideration.The operating procedures createtrunk groups and trunks in bothterminating points in parallel.Call Routing speeds up the con-figuration of the trunk networkand at the same time improvesthe quality of the operating ac-tivities. Call Routing supports theoperating sequence from thenew codepoint to the routes andtrunks. This greatly simplifies theoperation of the various routingmethods.

• SS7 ManagementSS7 Management is used forconfiguration and control of thesignaling network. Like Call Rou-ting, it is based on operating pro-cedures instead of individualcommands.The operating proce-dures create signaling links inboth terminating points in parallel.SS7 Management speeds up theconfiguration of the signaling net-work and at the same time im-proves the quality of the operatingactivities. SS7 Management sup-ports the administration of theMTP network and of the SCCPnetwork.

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Interfaces to other operatingsystems:

The EWSD NetManager providesdialog-oriented interfaces and re-port interfaces to other operatingsystems.

Via the dialog-oriented interfaces itis possible to carry out configura-tion tasks for service managementand network management. Theseinterfaces are based on the O&Mprocess and the operating proce-dures. The interfaces are specifiedin JAVA, while the transport of theinterface information is specified inCORBA or DCOM.

The report interfaces are used fortransmitting alarm data, billing data,performance data, monitoring data,and other data required for networkplanning. In this context the EWSDNetManager performs a concentra-tion and collection function, thuskeeping external operating sys-tems separate from the complexityof the data transport from theEWSD network node to the man-agement system.

In addition to the interfaces to theEWSD NetManager, EWSD alsocontinues to provide the standardinterfaces with the protocols theysupport (Q3, SNMP, FTAM/FTP).

Security measures

EWSD has a wide range of securitymeasures to protect against unau-thorized access to the system andits data.

The security measures are dividedaccording to the following func-tions:

– Administration of access rights

– Testing of access rights

– Identification and authentication

– Evidence collection and alarmprocessing

– Transmission security

– File and access protection

The administration of accessrights encompasses the allocationof authorizations with respect tousers, devices and applications, aswell as authorization categories.The authorization rights determinewhich commands can be used by auser or a device or application.

Whenever a command is entered,the testing of access rights checkswhether the user and the devicehave the required authorization.

The identification and authenti-cation of users is performed bymeans of user IDs and passwords.In case of external computer sys-tems, access authorization ischecked by means of the networkaddress, the processor name andthe application name.

Evidence collection is used toprove the presence of unauthorizedaccess to EWSD. Incorrect pass-words and unauthorized sessionsopened are recorded in cyclic files.

Alarm processing includes theactions taken to restore systemsecurity, such as sending an alarmto the system administrator, block-ing certain devices and processors,blocking user IDs, interrupting ses-sions.

For transmission security withrespect to data, the identificationand authentication of the transmit-ting and receiving parties arechecked. In addition, an accesscheck prevents unauthorized usersfrom using the resources requiredfor data transmission.

For file protection, the files areassigned certain protective infor-mation. When a file is accessed, allthe protective information taken to-gether determines whether or notfile access is permitted.

EWSD also includes access protec-tion against external access byapplications in TMN systems(telecommunications managementnetwork). Access protection oper-ates on the Q3 interface betweenEWSD and the TMN.

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File transfer

For file transfer to external systems,EWSD uses the FTAM function (filetransfer, access and management).FTAM, based on the ISO standard8571, forms an important compo-nent of the Q3 interface in theTMN.

FTAM is an application of the ISOreference model (layer 7). WithFTAM, file transfer is performedaccording to the client/server princi-ple. The client sets up the connec-tion and sends tasks to the server.The server performs the tasks andreturns the results to the client.

FTAM can assign access rights forall types of file access. In additionto read and write access to files onexternal computers, it is also possi-ble to create and delete files and toread and modify file properties.

FTAM operates independently ofthe physical storage of data on thepartner computer.

Subscriber line maintenance

A fully functioning subscriber line isrequired if a subscriber is to havereliable access to the services ofa telecommunications network.Operating companies therefore en-deavor to keep their subscriberlines free from faults and to clearany faults as soon as possible.

EWSD provides the greatest degreeof efficiency with respect to itsmaintenance measures for sub-scriber lines. These ensure rapiddetection and diagnosis of faults,thereby contributing to rapid faultclearance.

The maintenance measures applyto both analog as well as digitalsubscriber lines.

The integrated line test function(ILTF) detects a faulty subscriberline before the subscriber can evennotice the fault. By means of theperiodic access test (PAT), ILTFdetects faults as soon as theyoccur on subscriber circuits, sub-scriber lines or subscriber termi-nals. This test is performed everyfive minutes.

For analog lines, the PAT functionchecks the:

– Availability of the subscriberterminal

– Quality of the subscriber line

– Subscriber circuit

For digital subscriber lines, PAT per-forms a level-1 activation. Thischecks the availability of level 1 asfar as the network termination withthe subscriber.

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The ILTF testing functions are incor-porated into every subscriber linemodule.

The following facilities are availablefor manual testing of subscriber lines:

– Test unit (TU)

– Line workstation (LWS)

– Subscriber line test PC (LT-PC)

– Ringback service (RBS)

In the new DLUG with line modulesfor up to 32 subscribers, the ILTFfunction for manual tests can becalled up (instead of the TU).

External test equipment can beconnected to EWSD by means ofthe Metallic Test Access (MTA).

Trunk maintenance

The operating quality of a commu-nication network depends on theexistence of fully functioning trunksand SS7 lines, among other things.As it does for subscriber lines,EWSD also provides effective func-tions for enabling rapid detection,diagnosis and localization of trunkfaults.

The measures implemented inEWSD are divided into self-supervi-sion, routine testing and demandtesting.

Self-supervision is performed inthe GP and in the CP. It comprisesthe following functions:

– Supervision of connection setupand clear-down (call irregularitymonitoring)

– Supervision of trunks for certainpermanent events (noisy port)

– Supervision for permanentlyblocked trunks (permanenttrunks)

– Supervision of trunks forpermanent status

– Supervision of trunks forextremely long connections

– Supervision for faulty trunks(killer trunks)

– Supervision of trunks with SS7 signaling

– Supervision of PCM links

Routine testing is performed inaddition to self-supervision. A sep-arate test program exists for eachtype of trunk. The scope of thetests is determined by the charac-teristics of the testing facilities inthe network nodes at either end ofthe trunk.

Demand testing is initiated when-ever a fault is detected. It is usedfor detailed fault diagnosis and faultlocalization. It is also possible tocheck the operability of a trunk fol-lowing fault clearance.

The following test devices are avail-able for the routine and demandtesting of trunks:

– Automatic test equipment (ATE)and end-to-end test equipment(ETEAE)

– Trunk workstation (TWS)

– Test phone

– Automatic transmission measur-ing and signaling test equip-ment for international telephonetrunks (ATME2)

Maintenance

Maintenance activities on EWSDare restricted to the processing ofautomatically detected malfunc-tions (corrective maintenance).There is no need for preventivemaintenance.

Alarm surveillance reports theexact type of fault and its location,and the operating documentationprovides detailed instructions onfault clearance.

For software maintenance, the op-erational support of a Technical Ser-vice Center can be called in.

In case that repair is necessary,Siemens can provide a repair andreplacement service, supportingthe logistics of the operating com-pany.

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EWSD Structural Layout

Thanks to its consistently innova-tive hardware development, theEWSD system takes up less andless space. With its modular designand the increased use of plug-inconnections, the system can nowbe assembled in much less time.Meanwhile, installation test manu-als and acceptance test manualshelp to ensure a smooth installa-tion and acceptance of the networknode.

EWSD complies with the relevantinternational standards (Europeanstandard EN60950/ IEC60950) inrespect of human safety, protectionof property, electromagnetic com-patibility, etc. Compliance with thesestandards is confirmed by the CElabel in each rack.

The entire hardware of an EWSDnetwork node is housed in racks.The number of racks required canvary according to the capacitystage of the system. The racks areenclosed in cases, which have frontand back doors to ensure unre-stricted access to the interior.

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The racks are assembled alongsideeach other in rack rows. Simplesnap-in connections provide thecontact between the individualracks and ensure a safe groundconnection.

The rack rows can be assembleddirectly on the floor of the switch-ing room or on a special raisedfloor. A raised floor provides for un-derground cabling. In addition, acooling fan for the racks can bemade available from below. In caseof construction without a raisedfloor, a planar cable grid is providedabove the racks for cabling pur-poses.

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The racks hold the module framesand other system parts such as, forexample, air-circulator panels,power supply and fuses.

The module frames form bothphysical as well as wiring units. Inprinciple, each module frame con-sists of assembly rails, side sec-tions and guides for the modules,as well as a multilayer wiring board.In order to ensure complete elec-tromagnetic shielding, a moduleframe may be provided with topand bottom sheets as well as acontacting front cover.

The wiring board provides the elec-trical connections for the moduleframe. Blade-connector stripspressed into the wiring board formthe interface to the modules. Ifnecessary, the connectors of theblade contact strips are made longenough for the cable connectors tobe plugged in at the back. Corre-sponding centering strips or“cages” make sure that the cableconnectors are centered and thenlocked in the correct position.

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The module frames hold the actualmodules. The modules are all ofthe same format. On the front ofeach module is a faceplate, whichmay contain display elements,switches and front-facing connec-tors. The spring contact strips onthe back edge of the module formthe mating part of the blade-con-nector strips in the module frame.

The printed circuit boards of themodules are designed according tothe multilayer technique. They arepredominantly equipped withcomponents in keeping with sur-face-mounting technology (SMDtechnology). SMD technologysaves space and is particularlysuited to automatic production.

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EWSDFrom Planning to Operation

Technological progress, growingcustomer demands, and a market-place that calls for innovation areforcing network operators to mod-ernize their telecommunication net-works constantly. This may affectindividual network elements, theentire network, hardware, soft-ware, as well as operational andmaintenance strategies.

Each modernization measure hasits own peculiarities. On the basisof its many years of experience,Siemens can support network op-erators in their decision-making andin the implementation of modern-ization processes.

Siemens’ modular service conceptfeatures a complete portfolio ofservice packages that can be com-bined and customized to suit eachindividual customer’s requirements.The aim at all times is to maximizethe network operators’ incomewhile ensuring the greatest possibledegree of customer satisfaction.

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Project implementation

Siemens implements new networkcomponents or complete networks,including all tasks from the surveyto acceptance. Lower outlay onequipment and personnel, and areliable implementation schedule,are the result of efficient projectplanning.

This service package includes:

– Survey

– Site Preparation: Site Acquisi-tion

– Site Preparation: Civil Works

– Site Preparation: Infrastrucutre

– Network Configuration Planning

– Installation

– Commissioning

– System Acceptance Support

– Field Acceptance Support

Network Integration

The network integration servicepackage includes the integration ofnetwork components, integrationof features, expert technical advice,and compatibility testing of differentnetworks.

Siemens integrates individual net-work components to form a fullyoperational network according tospecific requirements. Networkgrowth is already taken into ac-count at the planning stage, so thatlater expansions do not present aproblem.

New features are the most con-vincing argument in competition.The objective of feature integrationis to incorporate the new featuressmoothly into the network.

WIth its interconnection service,Siemens offers expert technical ad-vice, interconnection proceduresfor checking the compatibility ofdifferent networks, and the entireequipment with measuring andtesting devices for performing in-teroperability tests.

PerformancePlus

Siemens offers a comprehensiveportfolio of customized after-salesservices. The PerformancePlus pro-gram from Siemens focuses on im-proved availability and increasingrevenue opportunities. The Perfor-mancePlus program comprises:

– Emergency Service

– On-call Support

– Fault Report Processing

– Software and Hardware Update

– Field Service

– System Quality Monitoring

– Repair and Replacement Service

Operational Support

Operational Support is called upon

• when temporary operational as-sistance is required

It allows network operators to startcommercial operation immediatelywith experienced network adminis-trators and to train their own quali-fied personnel.

• when network operation is tobe outsourced

Network operators pursuing a strat-egy of outsourcing of network op-eration profit from a cost reduction.

– Network Surveillance

– Maintenance Management

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Network Optimization

Modern communication networksare extremely complex and dynamic,with the result that they have to beoptimized repeatedly throughouttheir lifetime.

This service package guaranteesnetwork operators efficient use oftheir system resources and maxi-mum yield throughout the dynamiclife of their networks.This gives theoperators the assurance that theyare always one step ahead of theircompetitors.

Network optimization comprises:

– Technical analysis of the net-work and its environment

– Optimization concept includingNetwork planningUpdate and upgrade strategyExpansion strategyModification of network ele-ments (e.g. database)Roll-out plan

– Concept implementation

Marketing Support & Consult-ing

Siemens’ Marketing Support &Consulting portfolio includes manyattractive services that help opera-tors to maximize their revenue andensure continued business suc-cess.

Marketing Support is available for:

– making use of existing services

– improving competitiveness

– generation of new business

Siemens supports network opera-tors in:

– customized studies

– workshops and tutorials

– consulting projects

System Upgrade

Success in the marketplace de-pends on a modern network. Thesystem upgrade service packagesupports network operators in themodular upgrading of their net-works. It guarantees regular sys-tem upgrades throughout theentire lifetime of the product.

The service package comprises:

– customized upgrade procedures

– upgrade kits

– upgrade tests

– system upgrade support

– upgrade emergency service

These services include proceduraland personnel support and coverhardware and software upgradesboth for individual components andfor the network as a whole.

Project Management

Siemens also takes over the man-agement of complete projects. Insuch cases, network operators donot need to set up their own pro-ject organization. The project man-agement service package coversthe entire responsibility for reliable,fast and economical implementa-tion of the project.

This includes:

– Surveys

– Scope of work

– Materials purchasing and logistics

– Subcontracting

– Risk management

– Quality standards

– Financial issues

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Network Planning

This service can be used for bothnew and existing networks. Theservice includes:

– Consolidation of investment de-cisions

– Economic feasibility evaluation

– Creation of competitive advan-tages

– Process optimization

– Business protection

The most important steps in a net-work planning process are:

– Network analysis

– Network design

– Telco security services

– Network evolution

Training

Well-trained staff improve a com-pany’s efficiency and guaranteecustomer satisfaction.

As one of the oldest and most ex-perienced companies in the com-munications sector, Siemens hashad state-of-the-art training facili-ties and its own highly-qualifiedtraining staff for more than 45years. The training staff pass ontheir wide knowledge and experi-ence of the complex technical in-stallations.

Network operators benefit fromthe special training of all employ-ees, such as operators, OA&Mtechnicians, OA&M specialists ornetwork integration specialists, inthe form of optimum network avail-ability and fast introduction of newfeatures.

The training service package con-tains:

– Product-oriented training

– Network-oriented training

– Basic technology training

– Multimedia learn packages

– Performance integrator

– Business planning training

– Training documentation support

– Training assistance

– Training center certification

Siemens also offers special cus-tomized training, such as “Train theTrainer”.

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EWSDDocumentation to Meet all Needs

In accordance with the functions foroperating the EWSD system, theoperating documentation is dividedinto the areas of Information, Oper-ation, Maintenance/NonstandardMaintenance, Emergency and Ser-vice.The documentation consists ofinformational sections (Descriptions)and instructional sections (Manuals).The command language MML is theuser interface of EWSD.

The descriptions and manuals arewritten with respect to specific tar-get groups. The contents of eachare based on the area of utilizationand the task to be performed. Thedegree of detail in each case isdetermined with respect to theneeds of the intended user.

International standards

The EWSD operating documenta-tion is drawn up in accordance withthe following international stan-dards:

– ITU-T, series B, in particular B.10and B.17 (Blue Book I.3)

– ETSI ETS 300 834, ETR 313,EG 201 103 (Retrieval)

– ETS 300 498-1, ETS 300 498-2,ETR 081 (for Open Documenta-tion Architecture)

– SGML standard (ISO 8897,1986) Common TelecomDocumentation Type Definition(DTD) CTDV1.0 as EFTI recom-mendation

Languages

The EWSD operating documentationis available as standard in German,English and Spanish. However, thedocumentation can be translatedinto other languages, such asFrench, Portuguese and Russian,on the basis of a customer-specificagreement.

The MML command language existsin German, English and Spanish.

Formats

The EWSD operating documenta-tion can be provided in the follow-ing formats:

– SGMLSGML (standard generalizedmarkup language) is the mostpowerful platform-independentdocumentation format that existstoday. The advantage of havingEWSD documentation in SGMLformat is that it can be integratedtogether with the operatingdocumentation for other productsinto a single set of SGML docu-mentation. Through the use ofsuitable style-sheets, an operator-specific layout can be definedfor all providers.

– HTML / HTML + JAVAHTML is the format currentlyused for the dissemination ofdocumentation via the Internet.It is derived from SGML with toolsupport. HTML + JAVA has someadditional functions with respectto HTML (bookmarks, multiplewindows).

– PDFPDF is a platform-independentformat. It is derived from thePostScript format and thereforeis still based to a large extent onthe hard-copy display.PDF is also suitable for displayinginformation on a screen, offeringfunctions such as hyperlink andretrieval.

– PostScriptThe PostScript format is deriveddirectly from the editor functionof the publishing system of thesame name. PostScript is theelectronic stage before the paperprintout.

– PaperDocumentation on paper still hasits specific uses. The EWSDdocumentation is also availableon paper.

Documentation platforms

The EWSD operating documentationis primarily designed for electronicutilization.The presentation platforms usedthe EWSD NetManager.

The documentation is provided ona CD-ROM. A CD-ROM containingthe entire operating documentationis prepared for each project.

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EWSDQuality for the Entire Life Cycle

One of the most important corpo-rate goals of Siemens is to marketproducts and services that offer thecustomer the greatest possiblebenefit with the highest possiblequality.

EWSD attains its acclaimed highstandard of quality by incorporatingall the processes involved in devel-opment, production, sales and ser-vice into quality-assuring measures.Quality management, appliedthroughout the world, is based onthe ISO 9000 (and subsequent)standards, which are identical tothe EN 29000 (and subsequent)standards.

All work processes follow a set ofdocumented rules, guidelines andregulations, which are certified byindependent organizations. Theirapplication and observance is mon-itored by means of audits per-formed at regular intervals.

The audits refer to

– the quality system itself

– the process used and

– the product.

The results of the audit give anindication of how efficient the qual-ity-assuring measures actually are.They form part of an ongoingprocess to introduce additionalspecific quality improvements andto check their implementation.

All of the measures taken in qualityassurance – from drawing up theregulations, specifying the quality-assuring processes and performingthe quality audits – form part ofwhat is known as Top QualityManagement.

DQS, the German society for thecertification of quality managementsystems, has confirmed through itson-site visits that the quality man-agement system at the SiemensInformation and CommunicationNetworks Group has been imple-mented on the basis of the DINISO 9000 series. DQS has there-fore awarded its certificates to thisGroup in recognition of its achieve-ment.

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General system data

4,000,000 busy hour call attempts (BHCA), according to ITU-T recommendationQ.543 (depending on the features, the traffic distribution and the call mix)

Performance and reliability in accordance with ITU-T recommendations Q.541and Q.543

Transmission characteristics in accordance with ITU-T recommendation Q.551

Earthquake immunity in accordance with Bellcore TR-NWT-000063 (NEBS),Earthquake Zone 4

Lightning protection in accordance with ITU-T recommendation K.20

Human safety, protection of property, electromagnetic compatibility (EMC),etc. in accordance with international standards (EN60950 / IEC60950)

Compliance with the standards is confirmed by the CE label on each rack

Network interworking via internationally standardized system-integratedinterfaces to other networks

Clock accuracy, maximum relative frequency deviation plesiochronous 10-9,synchronous 10-11

Power dissipation in the busy hour < 1 Watt per line unit, depending on the sizeand configuration of the network node

Operating voltage – 48 V or – 60 V dc voltage

Technical Data

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EWSD PowerNode

600,000 subscriber lines

240,000 trunks

100,000 erlangs traffic capacity

RSU

50 000 subscriber lines

Line spectrum: analog subscriber lines (POTS), ISDN basic access (ISDN-BA),ISDN primary rate access (ISDN-PA), high bit-rate lines (UDSL, SDSL),2-Mbit/s leased line, Internet access, V5.1 interface, V5.2 interface.

Internal traffic

Inter-RSU traffic with RSUs connected to the same controlling EWSD network node

Traffic with other network nodes

Stand-alone operation

DLU

32-port subscriber line module

2000 subscribers per DLU (0.1 Erl.)

1550 subscribers per DLU (0.25 Erl.)

Line spectrum: analog subscriber lines (POTS), ISDN basic access (ISDN-BA),V5.1interface, high bit-rate lines (UDSL, SDSL), 2-Mbit/s leased line.

16 PCM30 systems

390 erlangs traffic capacity

Stand-alone operation

LTG

Line spectrum:

– up to four digital transmission links (PDC) with transmission rates of 1544 kbit/s or 2048 kbit/s (for trunks, remote DLUs or primary rate access)

– up to two digital transmission links with transmission rates of 4096 kbit/s(for local DLUs)

– access network via V5.2 interface (for up to four V5 links)

– integrated SDH (STM1) interface

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UI-LTG

Each UI-LTG provides 31 ports, i.e. 31 simultaneous userdialogs are possible.

Each UI-LTG consists of 1 OCANEQ module and 4 SCR modules.

Each UI-LTG supports up to four languages.Additional languages are possible.

SN

240,000 ports

2016 LTGs

100,000 erlangs traffic capacity

single-stage, non-blocking

n x 64 kbit/s

MB

2016 LTGs

ATM-based communication bypass

SSNC

1500 SS7 links

100,000 message signaling units per second (MSU/s)

> 4000 global title translations per second (GTT/s)

2 Mbit/s, 1.5-Mbit/s high bit-rate links STM/ATM signaling interworking between narrowband networks and broadbandnetworks

Stand-alone STP

CP

4,000,000 busy hour call attempts (BHCA) dynamic load

10 call processors

10 Mbit/s LAN interface

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EWSCountry

RSDLU

150, 400, 700 subscribers

OFDC

848 subscribers

Optical fiber ring, maximum length 1000 kilometers

Subscriber groups per line loop, max. of 63 (via remote terminal)

For each subscriber group, up to 64 ISDN subscribers oder 80 analog subscribers

CDE

15,000 subscriber lines

3700 trunks

SDE

3400 subscriber lines

960 trunks

RCU

5664 subscribers with up to 6 DLUs

Remote DLU

1920 subscribers (in the rack)

680 subscribers (in the shelter)

Container Network Node

17,280 subscribers in the 12,192 mm (40 foot) container

7680 subscribers in the 6058 mm (20 foot) container

1920 subscribers in the 2991 mm (10 foot) container

Trunks

Analog trunks with different loop and shunt resistance values possible

Digital trunks via 1544 kbit/s or 2048 kbit/s multiplex lines

All standard signaling systems, e.g. R1, R2, No. 5, SS7, as per ITU-T recommendation

All standard transmission systems, e.g. dc, ac, inband, outband, multifrequencycode, channel associated signaling (CAS), common channel signaling (CCS)

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Analog subscriber lines

Different loop and shunt resistance values possible

Pulse method with 5 to 22 pulses per second

Multifrequency dialing as per ITU-T recommendation Q.23

ISDN lines

Basic access with 144 kbit/s (2 B channels with 64 kbit/s each, 1 D channelwith 16 kbit/s, synchronization)

Primary rate access with 2048 kbit/s (30 B channels with 64 kbit/s each,1 D channel with 64 kbit/s, synchronization) or 1544 kbit/s (23 B channelswith 64 kbit/s each, 1 D channel with 64 kbit/s, synchronization)

Signaling in the D channel (transmission of signaling has priority overother packet data)

Call charge registration

All standard methods such as time pulse metering, automatic messageaccounting (AMA), interadministrative charging and statistics (IACHASTA)

512 tariffs

6 tariffs per zone

Tariff switchover possible at 15-minute intervals

Local storage of charges in the CP

Automatic backup of charges 8 times per day (more frequently for AMAdata)

Output for postprocessing via file transfer

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Mechanical design

Rack

Height: 2450 mm (8 feet) or 2130 mm (7 feet)

Depth: 500 mm (standard), 880 mm (optimized rack)

Width: 770 mm (standard), 600 mm (optimized rack)

Height including overhead cable shelf: 2655 mm or 2428 mm

Rack rows

Spacing: at least 1200 mm (from front edge to front edge) with an aisle width of 700 mm

Aisle width between rack rows in a container: 560 mm

Raised floor

Grid: 600 mm x 600 mm

Height: at least 300 mm from top edge of floor to top edge of raised floor

Point load per tile: 5000 N/m2 (500 kg/m2)

Permissible load capacity: 10 000 N/m2 (1000 kg/m2)

Space requirements

Local network node: approx. 27 m2 (10,000 subscribers)

Transit network node: approx. 22 m2 (10,000 trunks)

Permissible environmental conditions

In accordance with international standard ETS 300_019-1-3, Class 3.1,Operation in Central Office

Room temperature: +5° Centigrade to +40 ° Centigrade

Relative humidity: 10% to 80%

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Abbreviations

AAC authentication center

ACC automatic congestion control

ACD automatic call distribution

ADMOSS advanced multifunctional operatorservice system

ADSS advanced subscriber services

ALINA administration of language data for In-dividual announcements

AMA automatic message accounting

ATM asynchrous transfer mode

B BA basis access

CCAS channel associated signaling

CCG central clock generator

CDE compact digital exchange

CP coordination processor

CT craft terminal

DDCN data communication network

DECT digital European cordless telephone

DLU digital line unit

DLUG digital line unit G

DSL digital subscriber loop

DTMF dual tone multifrequency

EETSI European Telecommunications

Standards Institute

EWSD digital electronic switching system

FFTAM file transfer, access and management

FR frame relay

GGeoCENTREX Central Office Exchange Service

GUI graphical user interface

GTT global title translation

HHDSL high bit-rate digital subscriber line

HTI host timeslot interchange

HTRC hard to reach control

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IILTF integrated line test function

ILMP integrated line maintenance position

IN intelligent network

INDAS individual digital announcement system

INAP IN application part

IP intelligent peripheral

IP internet protokoll

IPI ISUP preference indicator

ISDN integrated services digital network

ISDN-BA ISDN basic access

ISDN-PA ISDN primary rate access

ISUP ISDN user part

ITU-T telecommunication standardizationsector of the International Telecom-munication Union

IVPS Integrated Voice Processing System

IPoP integrated point of presence

LLTG line/trunk group

MMAC multifunctional attendant console

MB message buffer

MIS management information system

MSB multifunctional switch board

MSC mobile services switching center

MSP multi service platform

MTP message transfer part

NNT network termination

OOA&M operation, administration and

maintenance

OCANEQ operationally controlled equipmentfor announcement

OFDC optical fiber distributed concentrator

OMAP operation, maintenance andapplication part

OSI open system interconnection

PPA primary rate access

PAT periodic access test

PBX private branch exchange

PC-CAPE cutting and programming equipment

PCM pulse code modulation

PCT post call time

PDC primary digital carrier

PDH plesiochronous digital hierarchy

PHUB packet HUB

PoP point of presence

POTS plain old telephone service

PPM periodic pulse metering

PSTN public switched telephone network

PTN private telecommunication network

QQSIG standardized signaling system (refer-

ence point Q)

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RRAS Remot access server

RBS radio base station

RDU radio distribution unit

RSDLU remote shelter DLU

RSU remote switching unit

RT remote terminal

RTI remote timeslot interchange

SSCP service control point

SCR speech recognition and code receiver

SDE small digital exchange

SDH synchronous digital hierarchy

SDSL symmetrical digital subscriber line

SLM subscriber line module

SMD surface-mounting technology

SMP service management point

SN switching network

SS7 signaling system no. 7

SSNC signaling system network control

SSP service switching point

SSS switching subsystem

STP signaling transfer point

TTC transaction capabilities

TCAP transaction capability application part

TMN telecommunications managementnetwork

TSC Technical Service Center

UUDSL universal digital subscriber line

UI-LTG user interaction LTG

VVLR visitor location register

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Contact us!Visit our website athttp://www.siemens.com/ic/networks/

Or send us a fax to +49-89-722-22994

!

COPYRIGHT© 1999 Siemens AGInformation and Communication NetworksICN WN CS PL D3Hofmannstr. 5181359 Munich, Germany

Order no. A30828-X1130-V-1-7618Printed in the Federal Republic of GermanyEW 13A (13, 14, 15)

This publication is issued to provideinformation only and is not to form part ofany order or contract. The products and services described herein are subject to change and availability without notice.

Siemens Aktiengesellschaft

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