NGN

NEXT GENERATION NETWORKS

(NGN)

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Content Development Team:

The contents of this course are developed by thefollowing Instructors:

Mr. Syed Irfan Sohail Dr. Mustafa ShakirMr. Muhammad SiddiqueMr. Sajjid-ur-RehmanMr. Qasim Mansoor JilaliMr. Farrukh S. BabarMr. Irfan KhalidMr. Muhammad HussainMr. Shahab Ahmad NiaziMr. M. Asharf JavedMr. Kashif JamilMr. Salahuddin

Course Objectives:

At the end of this course the participants are expected to:

•Identify differences in legacy networks & Next Generation Networks•Describe NGN Architecture and NGN Services•Describe NGN Signaling protocols and their workings •Identify media gateways and their connectivity•Describe current and future NGN trends regarding Multimedia Services

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Traditional Networks and their Services

• Voice Services:– Basic telephony– ISDN (Digital services)– Mobile Telephony

• Video Services:– Video telephony– Cable TV– Video On Demand

• Data Services:– Site-to Site Connectivity– Internet Access

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Traditional networks Services

Traditional circuit switches:

-Meant for voice services

-Connectivity & switching

-Short Holding time

Circuit switches for Data Calls:

-Internet calls

-Longer Holding time

-Less bandwidth and less revenue

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Legacy/Traditional Networks

Focus shifted from basic telephony and supplementary to Multimedia Services for users from any place and at any time

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Services

Transport & Access

Advantage: Beneficial as a standalone systems and solutions

Disadvantage:High operational costSlow to deployDifferent devices are required for different services

Traditional networks Services

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Access n/wAccess n/w

Switches

PSTN designed for POTS, basic copper wire line voice service

Traditional PSTN Voice networks

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Traditional Data networks

Frame RelayATM

IPVirtual Connections

Branch Office

Branch Office

Branch Office

Head Office

Public Data Networks: Providing data/LAN Connectivity

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HLR

VLR

MSC

GMSCBSC

OMC

Fixed Network

BTSs

Traditional Mobile networks

Public Land Mobile Network:Providing voice services to mobile and Fixed networks

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Traditional Internet network

Internet: Data services exclusively, packet switched network with some other services

Servers

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Complicated Legacy Traditional Network

More complicated networking and construction

High CAPEXSlower deployment of new service

High OPEX

Too many sites!

MSC2

MSC1

MSC5

MSC7 MSC8

MSC3

MSC4

MSC6MSC..

Need more investment on sites and accessories

Need more staff for O&M

Need more transmissions for inter-connecting

Need more time for service deployment and O&M

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Telecom Service Requirements and Future Trends

Voice95%

SMS5%

Voice

SMS

MMS

Info Services + surf

Location Services

Transactions

Business Data

Machine to Machine

Multi Media

Voice58%

（ 2002-2007 ）

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Future Trends

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Future Trends

1990 1995 2000 2005 2010

Multi-service Multi-protocol

Simple Integration

All in IP evolutionCircuit switching- 〉 packet switching- 〉 All in IP 3GPP R5-R6, 3GPP2 Phase0-Phase3

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NGN Evolution & its Overview

Desire for a new platform:

User requirements increased—more bandwidth

Technology growth—intelligent nodes, switches

Fast & reliable exchange of information—high transmission speed

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New services evolution

Arrival of new Telecom services, fast packet switching and enhanced VVD laid the foundation of a New Generation of Networks or NGN for new generation of services

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What is NGN?

• NGN is Voice Over IP, bypassing the regular switches to save the investment on Switches and Trunks.

• NGN is network convergent technology, combining wireline (PSTN), wireless (GSM, CDMA and 3G) and packet data network together, for integrated voice, data and multimedia services.

• NGN is a flat telephone network over Packet Data Network, instead of traditional Hierarchy structured telephone network with reduced investment.

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Why NGN• Increased demand for bandwidth is not possible through

existing PSTN.

• Requirement for new services.

• Telecom operators wants to reduce the OPEX and CAPEX (Need one common network for all services).

• Future proof network to handle Voice, Data and Multimedia.

• Optimising and simplifying transmission links.

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NGN - Drivers

Next Generation Networks


Operation Costcompetition

QoS configurability& verification

Meet capacityOn-demand

request

Rapid introduction of new technology Voice/Data and wire/wireless integrated managementInteroperability: Multi-vendor equipment

Rapid introduction of new technology Voice/Data and wire/wireless integrated managementInteroperability: Multi-vendor equipment

Demands for new services

Diversity in Technologies

Cope withIP & mobileenvironment

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IP/MPLS Multi-Service Bearer

NGN Core Network

VIDEOVOICE DATA

Copper Optical Wireless

PSTNPSTN

GSM/CDMAGSM/CDMA

Public Data networkPublic Data network

CATVCATV

SE

RV

ICE

SE

RV

ICE

SE

RV

ICE

AC

CE

SS

AC

CE

SS

AC

CE

SS

VOICE

data

data

VIDEO

VOICE

Legacy Networks & NGNLegacy Networks & NGN

Legacy Networks were dedicated and isolated networks with service specific signaling and routing for service connection

Limited Broadband and Multimedia services High OPEX High Service cost Long Service provision time Inefficient O&M Too many sites, too many types of nodes Outdated and aged Exchanges

NGN has a common IP core and provide nomadically accessible IP applications regardless of a specific access link or user device

Provide integrated services instead of limited service Centralized management and simple network structure,

reduce OPEX OPEX Saving from reduction of transmission, room

space, O&M center, etc. Realize the fast and cost effective new service

deployment. • Pave the way to all-IP network

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Voice and Data Networks

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Distributed Model

MG

IP

SoftSwitch

IP

H.248/MGCP H.323/SIP

TDM

TDM

Packet Network

Application Servers

O&M

Charging

IP Phone

Centralized Model

Call Control

Line Card

Trunk Card

Time Slot Switching

TDM

O&MCharging

POTS

Phone

Centralized vs Distributed ArchitectureCentralized vs Distributed Architecture

Basic & Supplementary Telephony services

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Harmonization thru Standardization

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Packet-based transfer Separation of control functions among bearer

capabilities, call/session, and application/ service

Decoupling of service provision from network, and provision of open interfaces

Support for a wide range of services and applications

Broadband capabilities with end-to-end QoS

Characteristics of NGNCharacteristics of NGN

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Interworking with legacy networks via open interfaces

Generalized mobility Unrestricted access by users to different

service providers Converged services between Fixed/Mobile Compliant with all Regulatory requirements,

for example concerning emergency communications and security/privacy, etc

Characteristics of NGNCharacteristics of NGN

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NGN Solution Benefits

Structured network architecture, smooth evolution, variety of services available

Rapid Service provisioning Cost-effective multi-service access One IP based multi-service bearer network Retain/expand customer base and increase ARPU

(Average Revenue Per User) FMC-Fixed Mobile Convergence Synergy IMS Ready

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• OPEX SavingsReduction in number of Switching nodes and

transmission linksReplacement of obsolescent equipment with new

generation IP SolutionsLower OPEX for new NGN nodes: easier network re-

engineering, less power consumption, less space needed

• CAPEX SavingsPay as you grow for Network expansion

NGN Solution Benefits

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SignalingModule

Trunk Module UserAccess Module

Service ServerSoftSwitch

TrunkGateway

TrunkGateway

TrunkGateway

SS7SignalingGateway

Contrast between PSTN and NGN

User AccessGateway

CPU

Switching Array

Intelligent Service Server

IP Core

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Evolution from PSTN to NGNEvolution from PSTN to NGN

Trunk gateway

Core switch

Call controlPacket core

network

LE

Soft switch

Tandem /toll exchange

LE

IN NMS App Server Policy Service

ISUP SG

PSTN

switch

STPTMG

PLMN

WMG (Wireless Media Gateway)

SIPPhone

H.323Phone

PCPhone

IADAMG

Packet core network

Soft switchSoft switch

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AN or Remote Unit

LS

PSTN NGN

MSTransitOffice 1

GatewayToll

OfficeOperation System SCP

MSTransit Office 2

Tandem Office to be-Reconstructed

MSAN

IP Network

NMSBilling & Customer Care APP server

Softswitch iHLR

OLT

ONU

ONU

ONUOptical Transmission

OLT

ONU

ONU

ONUOptical Transmission AN

LS

Transit Office to be-Reconstructed

Media GatewayMedia gateay

LS LS LS

FE/GEFE/GE

FE/GE

V5.2

Remote Module

Twisted-pair Cable E1E1

E1/SDH/SONET

PSTN Transit Office Optimization & Reconstruction Solution

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PSTN End-Office Optimization and Reconstruction Solution

PSTN NGN

ISDN Subscriber

DSL Subscriber

ISDN Subscriber

DSL Subscriber

Data Network

SS

Tandem Office

Gateway Toll

Office OS SCP

End Office to be-Reconstructed

LE LE

Media Gateway

E1/SDH/SONET

V5.2

FE/GE

Remote Module

Billing & Customer Care

NMS APP

iHLR

Subscriber

MSG7200 TGMSG 9000

SG7200 SG

AN orRemote Unit

Reconstructed End Office

FE/GE

FE/GE

DSLSubscriber

OLT

ONU

ONU

ONU AN

OLT

ONU

ONU

ONU MSAN

V5.2

E1/SDH/SONET

Twisted-pair Cable Twisted-pair Cable Twisted-pair Cable

Twisted-pair Cable

E1/MSTP/Build-in PDH/Build-in SDH

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NGN Architecture/Layer description and NGN Trends

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NGN Architecture

• Characteristics of Next Generation Network:• NGN is designed with an open network

framework.• NGN adopts the hierarchical architecture,

which is divided into media access layer, transport layer, control layer and service/application layer.

• NGN is based on standard protocols and packet switching network.

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NGN Hierarchical Architecture

Edge Access

Core Switch

Network Control

Service Management

Service/Application Layer

Control Layer

Transport Layer

Media Access Layer

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Access Layer

•Interworks between Core Packet Transport layer and various existing communication networks.

•Provides access of various communication terminals such as analog phone, SIP Phone, PC Phone visual terminal and intelligent terminals to the Core Packet Transport layer via various access gateways

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Core Transport Layer

The packet switching network composed of backbone transmission equipments such as IP router or broadband ATM switch as the bearer basis of the softswitch system.

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NGN Control Layer

• The control Layer combines the equipment

that manages signaling and call control

progress.

• The control handles the call setup and

controls the media gateways.

• Major components at this layer are the soft-

switches.

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Application Layer

Layer with various applications and services such as client oriented integrated intelligent services and service customization.

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NGN Network Architecture

Service Management

Network Control

Core Switching

Edge Access

IAD AMGBroadBand

Access

UMG

PLMN/3G

SG TMG

PSTN

UMG

Packet Core Network

Soft Switch Soft Switch

iOSSPolicyServer

ApplicationServer

SCPLocationServer

RADIUSServer

MRS

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Huawei U-SYS Network Architecture

Service Layer

Control Layer

Core Switch Layer

Access Layer

SoftX3000SoftX3000

3G AccessAMG5000IADBroadband

AccessPSTNPSTN UMG8900SG7000

PLMNPLMN

SoftX3000SoftX3000

IP Core Video GW

UMG8900

UMG8900

SIP/H.323 Phone

U-Path

ENIPPolicy Server

MRS6100IN

OSSiManagerN2000

LocationServer

PSTN

switchSTP

Open Eye2G

Terminal3G

Terminal

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ZTE NGN Architecture

SG MSAGNAS H323GW IAD WAGAccess IP PBX

ZXSS10 IAD Series

Broadband Access

PSTN/ISDN WirelessSS7 Network

IP Router/ATM switch

Core Packet NetworkCore Transport

Softswitch SoftswitchControl

ZXSS10 SS1 ZXSS10 SS1

Router ServerSCP AAA ServerApplication

ServerPolicy ServerService

ZXUP10 APP

AG

ZXSS10 A200

TG

ZXSS10 M100

ZXSS10 S100

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PSTN Access

TGSG

PSTN

IP Core

Softswitch APP NMS

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Control Stream

Media Stream

IP Connection

TDM Bearer Network

TG

IP Bearer Network

SGTG

CityA PSTN CityB PSTN

LS

MS LSTP

TS

LS

TS

MSLSTPHSTP

SG

SIP-T

TDM Connection

Softswitch Control Device

Signaling gatewayFE/GE FE/GE

Signalling Gateway

FE/GE

PSTN-IP Toll Traffic Splitting Solution

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Next Generation Network -Future

Metro Optical Backhaul

Resource Manager

POTS

Multi Service Edge Route

LAN

APIAD

SoftphoneSoftphone

POTSFMC

MSAN

InternetSIP Phone

XDSL/LAN/POTS

Residential Enterprise Mobile Scenario

PSTN

Media GW

SS7/TDM

SS7/V5.2/TDM

NMSENIP

Softswitch

APP Server 3rd Party

Resource ManagerSignaling GW

Multi Service Edge Route

User Profile Center

IP Core Network

IPTV SipPhone

AP

Convergence

Intelligence

Broadband

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POTS

LAN

APIAD

SoftphoneSoftphonePOTS

FMC

MSAN

InternetSIP Phone

XDSL/LAN/POTS

Enterprise

NMSENIP

Softswitch User Profile Center

IPTV SipPhone

AP

IP Core NetworkConvergence

Centralized user profile center and application layer

for service convergence and fast service deployment

Shared converged IP network for voice, data and mobile

Unified multi-service access node for diversified services, decreasing the number of access node,

Residential

Convergence-oriented

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Broadband-oriented


POTS

LAN

APIAD

SoftphoneSoftphone POTS FMC

MSAN

Internet

SIP Phone

XDSL/LAN/POTS

Softswitch User Profile Center

IPTV SipPhone

AP

Broadband

IP Core Network

Constructing high QoS network with large bandwidth

Introduce various broadband access methods to support broadband service deployment

Broadband

NMSENIP

Residential Enterprise

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Intelligence-oriented


POTS

LAN

APIAD

SoftphoneSoftphone POTS

MSAN

Internet

SIP Phone

XDSL/LAN/POTS

Softswitch

User Profile Center

IPTV SipPhone

AP

Broadband

Intelligence

Centralized user profile center, session control and application layer

•Bring intelligence to whole network

•Support fast unified service deployment

NMSENIP APP Server 3rd Party

IP Core Network

Residential Enterprise

Next Generation NetworksSignaling Protocols

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SIGNALING PROTOCOLSIN

NEXT GENERATION NETWORKS

H.323, SIP, MGCP, SIG-TRAN ETC

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• A services oriented network– Focus is on services

• Separation of services from Call Control – Switching & connectivity headaches are no

more in switches• Services are independent of the Network

– All services are independent of network control

• Open and Integrated – Multivendor environment designed by IUT &

IETF

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NGN What it actually is…..

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Distributed Intelligence of NGN

Centralized Intelligence

Distributed & Effective Intelligence

Intelligence Driven by CPE

Telephony world Internet world

NGN Services

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NGN Values

• Distributed and Open architecture

• Hierarchical architecture: four Layers

• It has an independent Network control Layer

• Easy Interfacing: for multiple vendor Gateways

• Based on Packet Switching and Standard Protocols

• It is a brand-new network integrating Voice, data and video services

Network operators should:

• Build on Core Competencies related to traditional transport services

• Eliminate inefficient current service-specific, proprietary solutions

• Enable carriers to deploy advanced services(all IP multimedia)

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Quantifying the NGN

• Signaling: used for establishing, controlling and monitoring the connections among networks and the end devices

• Provides the means (paths, ways or directions) to exchange Connection-related information

• Was simple in case of only voice • Became complex with Value Added &

Supplementary services

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Signaling in Telecommunications

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Signaling in NGN

• NGN signaling protocols: H.323, H.248, SIP, MGCP, Sig Tran, etc

User to User• Media Gateway Controller to MGWC• User to MGWC and MGWC to user• User to Soft switch and vice-versa

MGWC Protocol: H.248/MEGACO• Control of Media Gateways & media (voice, video) coding

Session Description Protocol: SDPCharacteristics of Audio/Video

Signaling Transport Protocol: (Sigtran)PSTN to NGN Internetworking

• Version 1—June 1996Multimedia conferencing on LAN,

Defined network elements & Call model

• Version 2—February 1998More efficient procedures

Authentication, encryption and security H.235

• Version 3– September 1999Expanded supplementary services H.450

• Version 5– June 2003Improved robustness, recovery from signaling errors

Use of DNS, URLs within H.323

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H.323 Signaling in NGN

• System and component Descriptions H.323• Call Model Description H.323• System Control

Packetization, message formats, H.225(Q.931)

channel negotiations H.245

• Audio Coding, Compression G.711, G.722, code standards, G.723, G.729

• Video Coding, compression H.261, H.263ISDN(video phones)

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H.323 Functions and standard references

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H.323 Components

• H.323 defines four major components for packet based communications:

Packet based N/W

Terminal

Terminal, Gateway, Gatekeeper, Multipoint Control Unit

MCUGateway

Terminal

Terminal

Gatekeeper

Terminals: Client endpoints in network say IP phones, PCs. Must support audio, G.711(64kbps) G.723.1, G.729, GSM & others

Gateways: Supports inter-operatability, translation between H.323 & PSTN, Transmission formats, Audio/Video trans-coding, optional elements

Gatekeeper: Admission control, Bandwidth control, address translation, communicates using RAS, manages all terminals, gateways, MCUs

MCUs: Supports multi-conferencing between 3 or more endpoints

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H.323 Components

• Client end points on the network• IP phones, PCs having own OS• Terminals running an H.323 protocols and the

multimedia applications.• Must support audio G.711 (64 kb/s). Several

compression coders G.723.1, g.729, GSM & others

• Should also have support for Video, data• Support for RTP used for packet media flow

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H.323 Terminals

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H.323 Terminals

Terminal Call Manager

RTCPH225

Call SigH225RAS

H245Call Cont

RTP

Audioappls

videoappls

G.771G.729G.723.1

H261H263 T120

Data

Transport Protocols & Network Interface

• Gateway provides connectivity between an H.323 network and a non-H.323 network

• By translating protocols for call setup and release

• Converting media formats between different networks

• Transferring information between the networks connected by the gateway.

• A gateway is not required, however, for comn. b/w two terminals on an H.323 network

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H.323 Gateways

• On the H.323 side, a gateway runs H.245 control signaling for exchanging capabilities

• H.245 call signaling for call setup and release• H.225 registration, admissions, and status

(RAS) for registration with the gatekeeper • On the SCN side, a gateway runs SCN-specific

protocols (e.g., ISDN and SS7 protocols)• Translation between audio, video, and data

formats may also be performed by the gateway

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H.323 Gateways

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H.323 Gateways

Interworking Call Control

Gateway Call Manager PSTN/ISDNSignaling

Call control

PSTN/ISDNSignaling

Link Control

Physical Interface

H245Control

SignRTP RTCP

H225RAS

H225Call Sign

Transport Protocol & Network Interface

• Considered brain of H.323 network• It is the focal point for all calls within the H.323

network• Provide services such as addressing, authorization

and authentication of terminals and gateways• bandwidth management and call-control services for

H.323 endpoints• An optional feature--Call-signaling routing. Endpoints

send call-signaling messages to Gatekeeper which are routed to destination endpoints

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H.323 Gatekeepers

• Gatekeeper provides bandwidth control by using messages, bandwidth request (BRQ), confirm (BCF), and reject (BRJ)

• For instance: A threshold for simultaneous connections in H.323 network is specified

• Gatekeeper can refuse for any more connections once the threshold is reached.

• The result is to limit the total allocated bandwidth to some fraction of the total available, leaving the remaining bandwidth for data applications.

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H.323 Gatekeepers

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H.323 Gatekeepers

Gatekeeper Manager

H225RAS

H245Control

Sign

H225CallSign

Billing Services

Directory Services

Security Services

Policy/CallMgt. Services

Transport Protocols & Network Interface

• MCUs provide support for conferences of three or more H.323 terminals

• All terminals participating in the conference establish a connection with the MCU

• MCU manages conference resources, negotiates between terminals in determining (CODEC) to use

• Handle the media stream• Gatekeepers, Gateways, and MCUs are logically

separate components of the H.323 standard but can be implemented as a single physical device

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H.323 Multi-point Control Units

• MCU has two Logical entities:Multipoint Controller

Multipoint Processor

• Multipoint Controller: Controls conference call for a Multicast(many users) or Unicast(to single user)

• Multipoint Processor: provides advanced functions in H323 like video mixing, audio mixing or video switching

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H.323 Multi-point Control Units

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H.323 Call Example…….

H.323 Gatekeeper

phonephonePSTN PSTNIP network

H.323 GatewayH.323 Gateway

H.225 describes how audio, video, data and control information be managedIn IP network in equipment having H.323H.245 are control signaling which includes receiving & transmitting capabilitiesLogical channel signaling etc

• Call Setup step-1:Discovery and Registration

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H.323 Gateway

H.323 GatekeeperGatekeeper Request

Gatekeeper Confirm/Reject

Who is my Gatekeeper

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H.323 Gateway

H.323 GatekeeperRegistration Request

Registration Confirm/Reject

Associate 212 NXX XXXXWith IP Address 12.10.2.2

Okay!


• Call Setup step-2:Discovery and Registration

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• Call Setup step-3:

H.323 Gateway

H.323 GatekeeperLocation Confirmation

Admission Request

Find where is 212 NXX XXXXCan I call that IP address 12.10.2.2

Yes, IP is identifiedThis much XX bps is may be used


Location Request

Admission confirm/reject

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H.323 Gateway

H.323 Gate

keeper

H.323 Gateway

Q.931 for basic callsetup protocol

ACFSetup

H.225 using Q.931

ACF

ARQ

Connect with OLC H.245Connect with OLC H.245


Logical channels for Media Streams

SetupH.225 using Q.931

• Call Setup step-4:

H.245 manages OLC like:Type of media, UDPPort # etc

ARQ

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H.323 Few Messages……..

Gatekeeper Discovery Location Request

Gatekeeper Discovery Request (GRQ) Location Request (LRQ)

Gatekeeper Confirmation (GCF) Location Confirmation (LCF)

Gatekeeper Rejection (GRJ) Location Rejection (LRJ)

Bandwidth Change Status Queries

Bandwidth Change Request (BRQ) Info Request (IRQ)

Bandwidth Change Confirmation (BCF) Info Request Response (IRR)

Bandwidth Change Rejection (BRJ) Info Request Nak ((INAK)

Terminal/Gateway Registration Call Admission

Registration Request (RRQ) Admission Request (ARQ)

Registration Confirmation (RCF) Admission Confirmation (ACF)

Registration Rejection (RRJ) Admission Rejection (ARJ)

• H.225: – RAS channel is used to carry messages used

in the GateKeeper discovery – Endpoint terminal registration

– Associates end-terminal address with its call signaling transport address

• H.225:

-- Also describes how audio, video and control information be managed in IP based n/w

77

H.323 (H.225 Call Signaling)

• H.245:– Receiving & transmitting capabilities– Defines procedures for managing logical

channels– Specifies as Open Logical Channel

structure like:– Type of media and format (audio, video codexs)– Transport address Port numbers– Direction of flow which port will receive info– May identify combinations of channels audio,

video

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H.323 (H.245 Control Signaling)

• Discovery & Registration: Identify/Who am I– RAS

• Call Setup: Who I want to call– RAS/H.225/Q.931

• Call Negotiation: Our capabilities– H.245

• Media Channel Setup: Let’s open an audio channel– H.245

• Media Transport: Send the audio– RTP/RTCP

• Call Termination: We are done– H.245/H.225/Q.931/RAS

79

H.323 Call Stages

• Call Setup is faster: few messages• Future protocol: SIP based phones• Has more capacity to handle more calls• It’s a newer version may discard backward

compatibility• Uses SDP like H.323 uses H.245 for messages• Establish sessions over purely IP networks for VVD• End-to-End oriented signaling protocol and similar

to HTTP

80

Session Initiation Protocol SIP

• An end-to-end oriented signaling protocol which means, that all the logic is stored in end devices (except routing of SIP messages)

• Establishes sessions for features: audio/videoconferencing, interactive gaming, and call forwarding

• Enables service providers to integrate basic IP telephony services with Web, e-mail, and chat services

• signaling functions are based on H.225 recommendation• specifies the use and support of Q.931/Q932 signaling

messages

81

Session Initiation Protocol SIP

• UAC make requests and the UAS return answers to client requests

• SIP defines the communication through two types of messages, The requests (methods) and the answers (state codes)

• “SIP Methods”– contains URI User Request Identifier called Request-Line

• “SIP Answers” (State Codes)– The answers or Responses of the above SIP Methods

82

SIP Messages, Call & Control

• To establish sessions SIP has following components to perform the session functions:

1. User Agent: UAC (sends/receives SIP requests)

UAS (sends answers to SIP requests)

2. Servers: Proxy (establishes calls between users)

Redirect (generates redirection answers)

Register (accepts register requests, gives location and address of user)

83

SIP Components

SIP relies on SDP(Session Description Protocol) to exchange session contents like H323 uses H245 for actual media exchange

(can all be in same machine)

84

SIP Call Setup Example

[email protected] [email protected]

From: [email protected]

[email protected]

Location Server

SIP Server

[email protected]: [email protected]

OK OK

ACK ACK

Media Stream

[email protected]

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SIP Call Setup Example

[email protected] [email protected]

From: [email protected]

[email protected]

Redirect Server

SIP Server

MovedContact 135.79.24.68

ACK

ACK

Media Stream

[email protected] From: [email protected]

OK

xyz? 135.79.24.68

• SIP entities identify a user by its SIP URI (Uniform Resource Identifiers)

• Examples of SIP URI: user@domain, where domain is a full domain name user@machine, where machine is the name of the machineuser@ip_address, where address is the IP address of the machinetelephone_number@gateway, where the gateway allow to access through the PSTN to the called number

86

SIP Entities and Address

* SIP identification solution, can be also based on the DNS

• SIP Messages: – INVITE --- Initiate Call– ACK ---- Confirm final response– BYE ---- Release Call– CANCEL --- Cancel request– REGISTER --- Register with LS

• SIP Response:

Client Error 404 --- Not found

Server error 500 --- Internal Server error

Client error 484 --- Address incomplete

87

SIP Messages & Responses

SDP describes: Type of media (V/V/D), format (CODECS G.729, G.731 etc), transport protocol (RTP/UDP/IP) and transport address (UDP port numbers)

88

SIP Requests & Responses few……

Requests (Methods) Respones (Answers)

INVITE Initiate Call 1xx Informational

ACK Confirm final response

2xx Success

BYE Release Call 3xx Redirection

CANCEL Cancel Pending request

4xx Failure of Request

OPTIONS

Features Supported 5xx Server Failure

REGISTER

Register with Location Server

6xx Global failure

• Used between SoftSwitch and IAD/AG/TMG/UMG

• The Softswitch (MGC) Controls Media Gateways by means of MGCP

• is a signaling and call control protocol used within Voice over IP (VoIP) systems that typically interoperates with the public switched telephone network (PSTN)

• In essence MGCP is a Master (softswitch) and Slave(Media Gateways) Protocol

• MGCP uses SDP for media transporting

89

Media Gateway Control Protocols-MGCP

http://en.wikipedia.org/wiki/Communications_protocol

http://en.wikipedia.org/wiki/Voice_over_IP

http://en.wikipedia.org/wiki/Public_switched_telephone_network

90

MGCP Call Flow Scenario

SG

SS

RTP/UDP/IP

phone phone

LE LE

TMG/UMG 1 TMG/UMG 2

SG: To establish call b/w PSTN & SS

IAM

IAMACM

MDCXCRCX

ACM

CRCX

RESP

LEGENDS: IAM- Initial Address MessageACM- Address Completion MessageCRCX- Create ConnectionMDCX – Modify connection (add video)RESP – Response to connection

Media Stream

91

MGCP Messages…….

Command Direction of Flow and Command itself

Endpoint Configuration

MGC to MG EPCX

Create Connection MGC to MG CRCX

Modify Connection MGC to MG MDCX

Delete Connection MGC to MG DLCX

Notification Request MGC to MG RQNT

Notify MG to MGC NTFY

Audit Endpoint MGC to MG AUEP

Audit connection MGC to MG AUCX

Restart In Progress MG to MGC RSIP

92

MGCP Call Flow Scenario

OFF Hook

ACM

ANM

IP NEWTORKRESP

RESP

MDCX

OFF hook

Ringing

IAM

MGCP

CRCX

MGCP

IAM

ACM

ANM

CRCX

RESP

Phone

MG2LEX1 MGC MG1

Phone

LEX2MGC

• MEGACO was designed after some limitations in MGCP like MGCP could handle low density

• ITU-T developed MDCP whereas IETF had developed MGCP

• A compromise between the two originated in the form of MEGACO-Protocol or MEGACOP

• ITU-T (SG-16) also developed H.248 in parallel to MEGACO

• Finally ITU-T & IETF agreed upon that both MEGACO & H.248 shall be identical

93

MEGACO/H.248, point of origin…

• MEGACO defines the rules/protocols for the Sofswitch to control MGWs

• Typically MEGACO/H.248 provides support for media streams

• It provides support for VoIP & multimedia support for PSTN or VoIP within the IP network

• MEGACO provides base architecture for controlling MGWs –how MGWs can be controlled by SS (MGC)

• MEGACO/H.248 works for a distributed architecture

94

MEGACO/H.248, functions

• MEGACO provides:• Total control over Media Gateways MGs• Call admission and billing• Signaling interface to PSTN• Translation for H.323 or SIP protocols

The Softswitch (MGController) instructs MGWs like:• To sense off-hook condition• To apply dial-tone & collect dialed digits• To ADD any call connection and its context (coders

required)• To add UDP port numbers etc

95

MEGACO/H.248, workings..

• Two terminologies are used:– Termination and Context

• Termination:– A termination is a logical entity that transmit/receive

media stream or control streams– For example: Endpoint is a termination

• Context:-- It is the association between two Terminations

(Endpoints)

For example: between two Endpoints (Local Call)

between two RTP ports (Transit Call)

96

MGCP and MEGACO base model

• MEGACO Terminations and Context

97


Termination Termination

Termination

Termination

Termination

Termination

X

X

SimpleContextVoice Call

MultimediaContext(Conference Call)

NullContextNo Connection

Context

Context

• MGCP terms basic constructs as Endpoints & Connections

Endpoints: source/sink of data

Connections: an association between two Endpoints

• MGACO terms basic constructs as Terminations & ContextsTermination: an entity within a MGW that source/sinks

data

Context: an association between two Terminations

Possible Contexts: Origin & Dest in same MGW (local call)

Between two diff MGW (transit call)98


• Sofswitch MGC creates new Context inside MG by ADD

• MGC adds, subtracts Terminations to a Context

• MGW NOTIFIES MGC of events (off-hook, on-hook) inside MG

• MGC audits (checks) Context & Termination between MGWs

• MGC uses Service Change command (adding video/data) during a call to inform MGW

99

MEGACO and SoftSwitch!

• MEGACO/H.248 define aspects of signaling as Packages:– Commonly defined functions like:

• Connectivity, Transfer and Hold etc• Examples of Packages are:

• Transactions = Number• Contexts = Number, $ • Termination = Identity or $• Package Data = off-hook, on-hook, port #• Events, Signals, statistics = ring back tones, tone

itself, time to ring

100

MEGACO Packages….

Messages Description of Messages

Add Addition of a Termination to a context. First Add message creates new context

Modify Modification of features of termination, dial tone

Subtract Removal of a termination fro a context (disconnection)

Move Removal of a termination from context and addition of this termination to another context (Conference Call)

Audit Value Requests Information about features, events, signalsWhen SS learns features like PRI/BRI or any other

Audit Capabilities

Requests Information about all possible features, events, signals allowed for this termination

Notify Notification on Events (off-hook, on-hook)

Service Change Notification of changes of termination like dead, bad

101

MEGACO Messages

• SIGTRAN:• SIGnaling TRANsport to carry SS7 signals over the

Internet• PSNT’s signals are being carried over IP network after

converting from SS7 to IP signals• Underlying transport vehicle is SCTP (Signaling Control

transmission Protocol) to carry SS7 over IP• PSTN signals SS7 are transmitted to SG (Signaling

Gateway) which in turns converts SS7 into SIGTRAN signals

• SIGTRAN signals are sent to a SoftSwitch or to next Signaling Gateway SG

102

SIGTRAN Protocols….

• Basic function of SIGTRAN:• To transport PSTN (SS7) signals over IP keeping

the functions & requirements of PSTN• Idea is to transport ISDN(Q.931, ISUP, SCCP

etc) messages between IP nodes (SG, MGC, MGW) or to an IP-based database

• To provide signaling capability for Call Management and to provide media paths for IP real-time traffic

• Real-time traffic can be Voice, Music, video which needs instant transportation

103

SIGTRAN Protocols……

104

SIGTRAN Protocols Model

Adaptation Protocols

Common Signaling Transport SCTP

Standard IP protocols

Adaptation protocols-to make TCP/IP look like an upper layer protocols MTP3 (which are MTP1, MPT2, MTP3 all SS7 signals)

Redefines newTransport service

Carries SS7 signalsover IP runway

The Real IP Standard Transport means

Upper Layer protocols

105

Integration of SS7 & IP protocolsSS7ISUP

SCCP users,RANAP, TCAP etc

Q931SCCP

M2UA SUAM2PA M3UA IUA

MTP3

MTP2

2904 3565 2905 9900 1401

SCTP

IP

• Ease of deployment: No need to distrupt SS7, future enhancements are transparent

• Better Efficiency: Using IP over SDH and IP over fiber can achieve much higher throughput

• Flexible architecture: IP signaling is flexible than TDM-based legacy networks

• Enhanced Services: Implementation of a core IP network facilitates a variety of solutions and value added services (VAS)

106

SIGTRAN benefits…..

107

All Signaling Protocol scenario….

SGSG

H.248

PSTN

AGW

SIGTRAN

H323 /SIP

SIP-T/BICC

SS7

GSM MSC

TMG/UMG

SS7

SIGTRAN

SS SS

SIP Phone

MAPPhone BPhone A

PSTN

phones

H248

TMG/UMG

E1E1

* SIP-T: SIP for Telephone

• ISUP—ISDN User Part• SCTP– Stream Control transmission Protocol• RANAP– Radio Network Access part• TCAP– Transaction Capability part• MTP1, 2 3 – Message Transfer Part 1, 2 ,3• M2UA, M3UA – Message 2 User Adaptation,

Adaptation 3• IUA– ISDN User Adaptation• SUA– SCCP User Adaptation• SCCP– Signaling Connection Control Point

108

Protocol abbreviation used….

109

NGN Components/Elements and their Description

110

Multi Service Core Network

Multi Service Core Network

Media Gateway

SG

Softswitch

Operation Support System Gateway (OSS-

Gateway)

NGN Elements

• Softswitch (SS or MGC)

• Media Gateway (MG)

• Signaling Gateway (SG)

• Core Network

• Management and Support

Systems

• Application and Feature Server

• NGN Protocols

111

Access Identities

• SG: Signaling Gateway

• TMG: Trunk Media Gateway

• AMG: Access Media Gateway

• UMG: Universal Media Gateway

• IAD: Integrated Access Device

• MSG: Multi Service Gateway

• BGW: Broadband GateWay

112

Introduction To Gateways

113

Media Gateways The function of a media gateway is to

adapt user data to the backbone network based on a packet switching technology (IP ).

Terminates voice calls from the TDM, compress and packetize the voice data, and delivers the compressed voice packets to the packet network.

Receives the voice packets from the packet network, unpacketize and uncompress them, and deliver them to the TDM.

Controlled by the Softswitch

114

Media Gateways as Access Gateways (AG)

V.24V.35E1

POTSISDNVOIP

ADSLADSL2HDSL

SHDSL

LAN

The AGW equipment is installed in the Access Network. The Access Gateway (AG) provides narrowband and broadband service access. The AG transfers subscriber line data such as voice, modem and fax across the core network of NGN through media stream conversion.

IP/MPLS

115

Media Gateways as Trunking Gateways (TG)

LocalExchange

LocalExchange

MGW MGW

TrunkExchange

Speech circuits (TDM)

TrunkExchange

IP packets

Trunk Media Gateway (TMG) is resident between the circuit switched networkand the IP packet switched network. It provides functions of format conversionbetween pulse code modulation (PCM) signal streams and IP media streams .

IP/MPLS

116

Residential Media Gateway (RG)

RMG adopts the Voice over IP (VoIP) technology to encapsulate analog voice signals into data packets that can be transmitted over packet-switched network, in order to provide telephone service over global IP network at a very low cost.

IP/MPLS

Customer

Premises

117

IAD: Full Series Products

1-port 2-port 4-port 8-port 16-port 32-port

IAD208 Series

IAD101A

IAD101E IAD102E IAD104E IAD108 Series

IAD132E(T)

IAD116E-A

EPhone

video terminal

Terminal

Capacity ranges from 1 port to 32 Optional FE/ADSL/VDSL uplink Support Fax/Modem

118

Huawei Universal Media Gateway: UMG8900

Large Capacity: 7168 E1, 112*STM-1 (Trunk side) POTS users: up to 1,000,000 V5 users: up to 1,000,000 PRA users: 7,168 (30B+D or 23B+D) BRI users: up to 500,000

Carrier-class reliability design Interfaces: E1/T1/STM-1.FE/GE,ATM STM-

1/E3 and POS STM-1/STM-4 Protocol supported:H.248, PRA,R2,

SIGTRAN(M2UA,IUA,V5UA) and V5 Local TDM switching function (128K*128K)

119

Connectivity Of Access Gateway in Network

120

Connectivity Of Universal Media Gateway

121

Connectivity Of Trunk + Signaling Gateway

122

Connectivity Of Trunk + Access Gateway

123

Connectivity Of Residential Media Gateway

124

Communication B/W Softswitch & UMG

125

Signalling Gateways

126

Signaling Gateway: SG7000

Process capacity: 5120 64kbps links or 640 *2Mbps links Interfaces: E1/T1 and FE Protocols supported: SIGTRAN (M3UA/M2PA/SCTP) and SS7 Built-in STP Embedded signaling trace analyzer

The Signaling Gateway (SG) converts PSTN signaling between TDM bearer mode and IP packets mode.

127

Signaling Gateways Function (SG-F)

• It encapsulates and transports PSTN signaling protocols

(eg. SS7) using SIGTRAN to the MGC-F or another SG-F.• For mobile networks, encapsulates and transports

PSTN/PLMN signaling protocols (eg. SS7) using SIGTRAN

to the MGC-F or another SG-F

• The interface from the SG-F to the other entities is a

protocol interface when the SG-F and MGC-F or other SG-F

are not co-located (eg. SIGTRAN).

• One SG-F can serve multiple MGC-Fs

• Application protocols include SIGTRAN, TUA, SUA and

M3UA over SCTP

128

Introduction To Softswitch…

• The control Layer combines the equipment that

manages signaling and call control progress.

• The control handles the call setup and controls

the media gateways.

• Major components at this layer are the soft-

switches.

129

• As a SoftSwitch product, SoftX3000 is located at the core control

layer of NGN scheme.

• SoftX3000 acts as a generic Call Controller in the packet-switched

network, supports the interworking between PSTN, H.323, SIP,

and MGCP domains.

• SoftX3000 provides H.248 and MGCP based bearer control.

• In the NGN solution of Huawei, SoftX3000 acts as the core of

NGN, interworking with other NGN components through the open

network adopting distributed standard protocols.

Softswitch…

130

Location of SoftX3000

• SoftX3000 is applicable to the network control layer of NGN and implements call control and connection management of voice, data and multimedia services based on the IP network.

131

Control Function Of S.Switch

SoftSwitchSoftSwitch SoftSwitchSoftSwitch

3G AccessAMGIADBroadband

Access

PSTNPSTNTMG

SG

PLMNPLMN

IP Core Network

UMG

UMG

Call control path

Talking Path

132

Next Generation Voice Switching the “Softswitch” concept

Soft switches are software-based multi-function network gateways (running under Unix or Windows)

that act as interfaces between circuit switched and packet-switched networks

133

Role of a Softswitch

Provides the call control and the Media Gateway control for the NGN

The name softswitch is used because many switching functions handled by large monolithic systems in the circuit switched world are instead emulated by software systems.

The term Softswitch refers to a Call agent or a Media Gateway Control (MGC)

134

MGW MGW

IP/RTP Media Packets

Call Signaling over IP

Media Gateway Control

Signaling

IP Core

Softswitch

Role of a Softswitch

135

Key components of softswitch architecture are:• Call agent / Call controller: it performs call control

functions

• Application Server (AS) provides enhanced features which is not available in Softswitch host.

• Operating Support System (OSS) as network management, billing support, etc.

• Signaling Gateway (SG) as interface to CCS-7 (STP)

• Trunk Gateway (TG) as interface to TE or LE of PSTN

• Access Gateway (AG) as interface to CPE

Softswitch System Architecture

136

Softswitch Functions

The main functions are:• Call control

• Media gateway access control

• Protocol processing

• Routing

• Authentication

• Charging

• Application Programming Interfaces (API) for 3rd party Servers

137

Softswitch Services• Softswitch can be used as an end office (C5 office),

tandem office (C4 office), toll office, International gateway office and IN SSP

• Voice services

– Basic voice services

– Supplementary Services

• IP fax services

• IP CENTREX services

• Multimedia services

• IN services

138

Softswitch Service Provisioning

• Basic and Supplementary Services– Abbreviated Dialing, Automatic call back, Alarm ring service,

Call waiting, Three-way call and Centrex, etc.

• Traditional IN services– 300, 800, Account card service, etc.

• New Revenue generating services– Web 800, Click to dial, Web Service Customization,

Synchronization browsing, One Number, Voice Mail, Unified Message (UMS), Short Message.

• Video and Multi-media services– Video phone, multi-media TV conference.

139

Huawei Softx3000 Softswitch

Legacy Switch

SoftX3000

High Capacity & Integration 2,000,000 POTS 2,000,000 V5 Subscribers 2,000,000 SIP Terminals 1,000,000 H.323 Terminals

High Performance 16M BHCA

Perfect Scalability 150,000 subs / frame and

smoothly expansion Fewer power Consumption

Power consumption < 4.5KWBig Saving of 40% OPEX !

Nodes, Space, Power, Staffs……

140

Softswitch Networking Solutions

• Long Distance VoIP Solution with Softswitch + Trunk Gateway configuration for long distance VoIP service.

• Local VoIP Solutions with Softswitch + Media Gateway, Softswitch+IAD、 Softswitch+AccessGateway, Softswitch+Intelligent Terminals for local VoIP and Data services.

• Flexible access solution for group subscribers such as school, enterprise, government institute depending on network condition and accessing scale.

141

SoftX3000

UMG8900

iManager

SoftX3000

UMG8900（Main control

frame）

IN

IP corenetwork

LMT

PSTN

EnterpriseUser

UMG8900（Userframe）PBX V5 AN

CDMA 450

SoftSwitch as a Class 5 Solution

142

Soft Switch as a Class 4

SoftX3000

UMG8900

H.248/SIGTRAN

AppServer Route/PolicyService

SNMPPARLAY/SIPINAP

Switch

H.248/SIGTRAN

NMS

SoftX3000

UMG8900

SIP-T/BICC

IN

LDAP/TRIP

Packet/TDMbearer netwrk

Switch

SS7/PRI/R2 SS7/PRI/R2

PSTN PSTN

143

Interface and Protocol

• An interface is the connection point between two

adjacent network entities, and a protocol specifies the

principles to be followed for information interchanging

over such connection points (interfaces)

• Different protocols are usually used on different

interfaces and maybe on the same interface as well.

144

Soft Switch Interfaces and Protocols

MRS

IADAMG

TMG

SG

SIP

SIGTRAN

H.248

MGCP

MGCP/SIP/H.323

MG

CP

/ H

.248

EPhone

SIP

SIP

H.323

MML/SNMP

NMS

FTP/FTAM

BC

Soft SwitchSoftSwitch

SS7

H.323

PSTN

SCP

INA

P

PA

RL

AY

APP Server

SIP

/INA

P

MG

CP

/ H

.248

145

SoftX3000 Signaling Classification

• Signaling transport protocol – Signaling transport layer protocol provides SoftX3000 with signaling transport services. These are MTP (PSTN), INAP (IN), M2UA,M3UA (User adaption layer protocols for MTP2 & MTP3),SCTP etc.

• Bearer control protocol - is a kind of master/slave protocol used for Media Gateway Controller (MGC) to control Media Gateways (MGs) from external call elements like a Call Agent (SoftX3000). Example is MGCP and H248(MEGACO).

• Call control protocol – A protocol used to control call setup, connection and termination. The call control protocols used in SoftX3000 are ISUP of SS7 & for switched circuit network, SIP and H.323 for call control in packet switched networks.

NGN Gateways & Application Servers

146

NGN Gateway Systems Access/Residential Gateway

• Network Access Gateway (including Firewall, NAPT, DHCP etc.)• Residential Border Gateway

• Media Gateway• Access/Trunk Media Gateway

• Radio Gateway• BRAS (Broadband Remote Access Server)

Softswitch• Call Server, Session Controller• Signalling Gateway including Media Gateway Controller

PSTN Gateway• PSTN Emulation and Simulation

Trunk and Border Gateway• Interconnection Border Gateway

Application Server Gateway• Parlay/OSA Gateway• OperAPI Gateway

147

NGN Control and Management System -1

Transport Resource/Policy Control System• Transport Policy Management System including PDF/PEF• Multimedia Resource Controller or Resource Manager• Bandwidth Broker and Bandwidth Manager

Mobility Support System• HLR/VLR, HA/FA etc.• Location Service Control System

• Location Control Server Packet Gateway Control System

• Various Gateway Controller including Media Gateway Controller

Network Access Control System• Admission Control and gate control system• DHCP Server, NAPT, Firewall etc

148

NGN Control and Management System - 2 IMS-based Session Control System

• P-/I-/S-CSPF• Session Control Proxy System (i.e., P-CSCF, Proxy VoIP

Gateway, etc)• IMS-MGW (Media Gateway) and IMS-MGC (Media Gateway

Controller)• IMS-Resource Controller

User Profile Database System• Including Transport/Service/Terminal/User Authentication and

Authorisation System• AAA Server, HSS etc.• User (and Terminal) registration system• Subscription Location

149

NGN Control and Management System - 3

Charging and Billing System• Charging Trigger and Charging Collection System• Online Charging System including Rating system• Account Management System

Traffic Management Server• Traffic Management System

Application Control Server• Broadcast Control Server• Home Gateway Control Server• RFID Control Server• Multimedia Application Control Server

150

NGN Application Systems Home Gateway

• Including intelligent Home server• STB Management Server

Media Resource Processing Server• Media Resource and Processing Gateway• Multimedia Resource Function Processor

Application Server• Interactive Application Server or SIP-based Application

Server • Messaging Server, Presence Sever, Conference Server• VoD Streaming Server, IP-TV or DMB Server• OSA Application Server• RFID Server, Telematics Server• Web Hosting Server

151

Gateway Controller

• The Gateway Controller is one of the key functional units of the Softswitch.

• The Gateway Controller holds the call processing rules, but uses the Media Gateway and Signaling Gateway to perform the job. It is the responsibility of the Signaling Gateway to perform call set-up and teardown.

• In addition, it interfaces to the OSS and BSS systems. Often this unit is referred as Call Agent or Media Gateway Controller interchangeably.

• Sometimes the Call Agent by itself is referred as a Softswitch.

• This component communicates within other parts of the Softswitch and also the external networks using different protocols.

152

Gateway Controller

• The Gateway Controller is responsible for bridging networks with different characteristics, including the PSTN, SS7, and IP networks.

• This bridging function involves validation and initiation before establishing phone connections.

• It is responsible for managing voice and data traffic throughout the various networks.

• It is often referred to as a “Call Agent” (because of its Call control messaging functions).

• Also is referred to as a “Media Gateway Controller” (because of its Media Gateway Control functions).

153

Functional RequirementsGateway Controller

• Call control engine• Voice call establishment protocols: H.323, SIP• Media control protocols: MGCP, Megaco

H.248• Class of service and quality of service control• SS7 control protocol: SIGTRAN (SS7 over IP)• SS7 processing (when using SigTran)• QoS related protocol message handling such

as RTCP

154

• Routing, including:– Routing component: local dial plan (E164 to port mapping)– Digit analysis overlap and/or inblock signaling– Digit translation support for IP, FR, ATM and other networks

• Call Detail Records (CDR) for billing• Bandwidth management control• Provisioning for Media Gateways:

– Assignment and real time configuration of DSP resources– DS0 channel assignments– Voice transmission (coding, compression, and packetization)

• Provisioning for Signaling Gateways:– SS7 variants– Process Timers– Linkset configuration– Point code or routing configuration

• Gatekeeper registration

155

Functional RequirementsGateway Controller

System Characteristics Gateway Controller

• It is CPU intensive. A multi-processor system is most preferred

• A large in-memory database required• A large memory capacity will also enable multiple

processes to live in memory without excessive paging activity.

• It deals mostly with IP traffic • A sufficient amount of high-speed connectivity may be

required• A dual-redundancy approach for network connectivity

is normally required• It requires support for a variety protocols• Disk storage is primarily used for logging

156

Signaling Gateway

• A Signaling Gateway creates a bridge between the SS7 network and an IP network, under the control of the Gateway Controller.

• A Signaling Gateway causes a Softswitch to appear like an ordinary SS7 point code (SS7 node) in an SS7 network.

• The Signaling Gateway only handles SS7 signaling; a Media Gateway handles the voice circuits established by the SS7 signaling mechanism.

• SIGTRAN defines a suite of protocols and user adaptation layers for transporting signaling information over IP-based networks.

• If SigTran is used as the protocol between the Gateway Controller and the Signaling Gateway, then only MTP1, MTP2, and SigTran reside on the Signaling Gateway

157

A Signaling Gateway usually supports the following layers: SCTP, which is responsible for reliable signaling

transport, streaming, congestion avoidance and control

M3UA, which supports the transport of ISUP, SCCP, and TUP messages over IP

M2UA, which supports congestion control and the transport of MTP3 messages

IUA, which supports the Q.931/Q.921 interface M2Peer, which supports the MTP3-to-MTP2

interface

158

Signaling Gateway….

Functional Requirements Signaling Gateway

• A Signaling Gateway must support the following functions:• It must provide physical connectivity to the SS7 network

via a TI/El or Tl/V.35 physical connection• It must be able to transport SS7 information between

Gateway Controller and Signaling Gateway via an IP network

• It must provide a transmission path for voice, video, and optionally data. (Data transmission may be supported within the Media Gateway.)

• Provide Highly Available SS7 operation for telecommunication services

159

System Characteristics Signaling Gateway

A Signaling Gateway has the following system characteristics: It is I/O intensive, but not very CPU intensive. A maximum amount of memory should be

available to hold state information, configuration information, the point code map, alternate routes, etc.

A disk storage is primarily used for logging; a small capacity may be adequate.

The Ethernet interface (to the IP network) may require dual redundancy.

160

Signaling Gateway Characteristics

It may interface with the SS7 network by using a T1/E1/E1, with a minimum 2 D-channels, and a maximum 16 D-channels.

Performance and flexibility can be increased using a H.110 or H.100 bus.

High Availability is a requirement, multiple Signaling Gateways or signaling links are available. Redundancy is built into SS7 networks by design

161

Convergence of SS7 and IP networks

162

Call Control Functionality

163

164

SEGway X401 Signaling Gateway

• Ability to scale upto 1408 SS7 links with HSL, 1000SIGTRAN M2PA/M3UA/SUA associations.

• 14 slots available for I/O and application server blades thus unprecedented flexibility to interface with traditional SS7 and IP-SIGTRAN networks

165

SEGway X301 Signaling Gateway

• Ability to scale upto 128 SS7 links

• Six payload slots available for low TDM and high speed (IP-SIGTRAN) this solution can be used to manage SS7 networks and connect with multiple interconnectivity partners.

Application Server

• Application Server generates application documents (VoiceXMLpages) in response to requests from the Media Gateway via the internal Ethernet network.

• The application server leverages a web application infrastructure to interface with data stores (messages stores, user profile databases, content servers) to generate documents (e.g., VoiceXML pages).

• AS provide interoperability between applications like WAP, HTML, and voice allowing the end user to simultaneously input voice command and receive presentation via WAP or HTML.

166

Application Server vs. Media Server

Application Server

IP Network

Media(RTP)

Signaling (SIP)

Media Server

Functions of a Media ServerAudio Tones &

AnnouncementsAudio Tones &

AnnouncementsDTMF Detection

& GenerationDTMF Detection

& GenerationAudio Bridging

& MixingAudio Bridging

& MixingAudio Recording

& PlaybackAudio Recording

& Playback

SpeechRecognition

SpeechRecognition Text to SpeechText to Speech

VideoAnnouncements

VideoAnnouncements

Video Bridging& mixing

Video Bridging& mixing

Video Recording & Playback

Video Recording & Playback

Fax Detection& Processing

Fax Detection& Processing

Hot WordSpotting

Hot WordSpotting

Video SwitchingVideo Switching

Video Transcoding

Video Transcoding

AudioTranscoding

AudioTranscoding

Media Server Control (SIP with

VoiceXML,MSML)

Com

man

d Resp

on

se

Functions of an Application ServerService Specific Logic

(ACD, IVR, Conf, Speech)Service Specific Logic

(ACD, IVR, Conf, Speech)

Service Mgmtand ProvisioningService Mgmt

and Provisioning

Call SignalingCall Signaling

Service Databases(ie. for screen-pops)Service Databases

(ie. for screen-pops)

Billing InterfaceBilling

Interface

Service CreationService Creation

RTP = Real Time ProtocolSIP = Session Initiation Protocol

167

Aims of Application Servers

• For building integrated, enterprise-class applications that share information, deliver services, and automate collaboration among networked companies at Internet volume and speed• separate of presentation, business logic, and data• provide the underlying core functionality necessary for

the development and deployment of business-driven application

• connect legacy systems, and Web Services

168

The Reason to Adopt A.S

• applications with complex business logic• potentially servicing tens of thousands of

concurrent users in real-time• require a scalability and reliability• Distributed system

– Stock trading system– Banking application

169

What we need

• RMI• Load balancing• Transparent fail over• Back-end integration• Transaction• Clustering• Dynamic redeployment• Clean shutdown

• Logging and auditing• System management• Threading• Message-oriented

middleware• Object life cycle• Resource polling• Security• Caching

170

What do they provide?• Speeds application development and relieves developers of the

effort and expense of creating these crucial services on their owno Load balancingo Fault toleranceo Web Serviceso Legacy integrationo Transaction managemento Securityo Messagingo Multi-threadingo Persistenceo Database connectivityo Resource poolingo Development, testing, and packaging facilities

171

Single Server/Clustered Servers

172

J2EE based…

• BEA WebLogic Java Application Server • IBM WebSphere Java Application Server• Oracle 9i Java Application Server • Sun ONE Java Application Server (iPlanet)• HP Application Server (HP-AS) (Bluestone)• JBoss Application Server • Enhydra Application Server

173

J2EE Components used..• Java Servlets & Java Server Pages (JSP)• Enterprise Java Beans (EJB)• Java Transaction API (JTA)• Java Transaction Service (JTS)• Java API for XML Parsing (JAXP)• Java Messaging Service (JMS)• Message Driven Beans (MDB)• Remote Method Invocation (RMI)• Java Database Connection 2 (JDBC2)• Java Connector Architecture (JCA)• Java Naming and Directory Interface (JNDI)• JavaBeans Activation Framework (JAF)

174

Three layered architectureof A.S

• The presentation layer – managing the user interfaces of applications,

including desktop applications, Web browsers, and pervasive devices

• The business layer– contains the business logic

• The back-end layer– provides connectivity with enterprise systems

and databases

175

Hosting Organization

Presentation

Persistence

LogicLogic

Subscriber 1

Subscriber 2

Subscriber 3

176

Three layered architectureof A.S

Presentation Layer

• Thin clients– such as Web browsers that send HTTP requests

and receive HTTP responses for static HTML or dynamic Web pages built by Java Servlets and Java Server Pages (JSPs)

• Thick clients– such as Java applets and applications, ActiveX

controls, or Visual Basic clients that run on a desktop and communicate with BEA WebLogic Server through CORBA, Java RMI,IIOP, or COM+

177

Presentation Layer

• Pervasive devices– including wireless phones, PDAs, smart appliances,

and other emerging remote clients that communicate with the server via specific and usually very compact • can generate WML pages from Servlets and

JSPs.• Web Services

– that connect to the system using Web Services technologies, such as SOAP,UDDI, and WSDL

178

Presentation Layer

• Provides a Web Server• Servlet and JSP results caching and JSP tags

caching• provides high-reliability, scalability, monitoring,

and other features required by enterprise applications

• plug-ins for Apache, iPlanet, and Microsoft IIS Web servers

179

Additional Features• Virtual hosting

– www.company1.com and www.company2.com• Clustering

– scalability and high-availability– insulates clients from hardware or power failures by

eliminating single points of failure• Load balancing

– Incoming requests can be distributed across multiple instances of AS

180

Additional Features

• High availability with transparent fail-over • The data contained in Web components can

be replicated across multiple machines• In the event of a failure, current client session

information is maintained• disk-based persistence• in- memory replication of a client ’s session state

181

Business Layer

• contains the application’s business logic independent of the user interface, including distributed components, running in the application server environment

• Enterprise Java Beans

182

Examples of transactions involving mail application server

• Establishing connection between mail APIs (application program interfaces) and mail server

• Updating mails by inserting, adding, replacing, or deleting

• Querying for the mails• Terminating the connection between the API and the

mail server

183

Responses to Requests by An AS

The server Gets from the collaborating or

independent mobile devices of an

enterprise From a distributed mobile computing

system The server processes these requests Generates responses

184

Examples of web database and enterprise application servers

IBM DB2 database server IBM DB2 is an RDBMS (Relational Database

Management System) data server from IBM

DB2 EveryPlace version run on handheld devices

Enterprises application logic processing at the server

185

Examples of web database and enterprise application servers

• Oracle 9i database Server RDBMS Oracle9i server has a large number of features and it supports XML documents and has an option for cluster database

186

Some Application Servers

Web Generic application servers for Java-based web applications (Microsoft, Sun, and Netscape) with additional support for wireless network and mobile devices

IBM WebSphere Application Server with specialized mobile Web computing application server (it supports J2EE Web applications and XML databases)

IBM Domino Application Server for workgroups, email applications, and support for handheld and Windows CE devices

187

Some Application Servers

Microsoft Mobile Information Server (e.g., for messenger and email)

Oracle 9i Application Server for database services with mobile support

Puma and Synchrologic iMobile Suite for data-synchronization services

Nokia WAP (Wireless Application Protocol) Server for wireless Internet WAP applications

BlackBerry Enterprise Server (BES)

188

189

Java Naming and Directory Interface (JNDI)

• Client API provides naming & directory services for Java Apps

• Does not replace DNS, CORBA, RMI etc

• Allows multiple directory services co-exist

• Provides a federated name server

Databases

• JDBC (Java Database Connectivity)– Thin clients – servlet,JavaServer Pages (JSP)– Thick clients – RMI to remote databases– most recommended way is to use entity

beans and benefit from the underlying services

– Connection pooling

190

Integration• Integrating new applications with any legacy

Enterprise Information System (EIS)• J2EE Connector Architecture (J2CA)• CORBA

– integration with legacy systems that implement the CORBA specifications

• COM/DCOM (COM+)– bi-directional interoperability with Microsoft ’s COM+

• can access data in Microsoft applications, communicate with Visual Basic clients

191

J2EE Connector Architecture (JCA)

• A standard architecture for connecting the J2EE platform to heterogeneous EIS systems– ERP, mainframe transaction processing,

database systems, and legacy applications not written in the Java programming language

– enables the integration of EISs with application servers and enterprise applications • By defining a set of scalable, secure, and

transactional mechanisms

192

• Enables an EIS vendor to provide a standard resource adapter for its EIS

• The resource adapter plugs into an application server, providing connectivity between the EIS, the application server, and the enterprise application

• An EIS vendor needs to provide just one standard resource adapter which has the capability to plug in to any application server that supports the J2EE Connector architecture

193


• Multiple resource adapters are pluggable into an application server

• enables application components deployed on the application server to access the underlying EIS systems

194


J2EE Connector Architecture

195

Resource Adapter in A.S

• To achieve a standard system-level pluggability between application servers and EISs, the J2EE Connector architecture defines a standard set of system-level contracts between an application server and EIS

• The resource adapter implements the EIS-side of these system-level contracts

196

• System-level software driver used by an application server or an application client to connect to an EIS

• By plugging into an application server, the resource adapter collaborates with the server to provide the underlying mechanisms, the transactions, security, and connection pooling mechanisms

• A resource adapter is used within the address space of the application server

197

Resource Adapter in A.S

Application Contract• An application server and an EIS collaborate to

keep all system-level mechanisms, such as transactions, security, and connection management, transparent from the application components

• A Connection Management contract • A Transaction Management contract • Security contract • A Message Inflow contract • A Lifecycle Management contract • A Work Management contract

198

Web Service Support• Automatically wraps the business components in to

Web services• Support for WSDL and UDDI

– Publish, search, host• Support for Web Services Security standard• Reliable SOAP implementation

– based on a sequence of asynchronous SOAP communications, receipts, and notifications

– guaranteed delivery, “exactly-once ” delivery, ordered conversation

• A set of convenient graphical tools for development, search, and composing of the Web Services– BEA WebLogic Workshop

199

Messaging

• Asynchronous method invocations • Why?

– Performance– Reliability– Support for multiple senders and receivers

Application ApplicationMessage Oriented

Middleware

200

Message Oriented Middleware MOM

• Provides– Guaranteed message delivery– Fault tolerance– Load balancing of destinations– Subscription mech.

• Proprietary solutions– Tibco Rendezvous– IBM MQSeries– BEA Tuxedo/Q – Microsoft MSMQ

201

Java Message Service

• API– Write code to send and receive msg

• Service Provider Interface (SPI)– Plug in JMS drivers

• to allow existing companies to JMS-enable their applications without impacting client-side development

• Supports– Publish/subscribe– Point-to-point

202

203

JMS Connection Factory

JMS Connection

JMS Session

JMS Producer

Or

JMS Consumer

Serialized Message Connection

NamingService

Client

JNDI

4:Lookuo JMS Destination

1:RetrieveJMS Driver Connection Factory

2:Create Connection

3:Create Session

6:Send or Receive Message

5:Create Producer or Consumer

JMS Driver Client Runtime

Java Message Service

Security in A.Servers

• Java Authentication and Authorization Server (JAAS)

• Encryption• Auditing• HTTPS, • basic HTTP authentication with Base64 encoding

for services protected by firewalls• Role based security

– User and group definition– Built-in security data store retains the role,

profile, and entitlement data, and is built on a highly optimized LDAP directory

• Single Sign-On• WS-Security

204

Next Generation Networks NGN

Services Capabilities

205

206

Service Capability Of NGN

207


PSTN

App ServerMCU

MRS

SCP iOSS

TG

SoftswitchSoftswitch

Unified Communication

POTS FAXWeb800

OpenEye Video Phone Video Conference

UPT&CRBT

208

PSTN Service

Modem PBX

100 ％ inherits all PSTN services 100 ％ inherits all PSTN services

NP

Video conference

Simultaneous Ringing

VAS

Wide Area Centrex

Value added servicesValue added services

Open service system

Flexible & quick service deploymentFlexible & quick service deployment

IP Centrex

Solution for enterprise userSolution for enterprise user

Telephone Fax

INAP CS2 Parlay API

SIP


209

Service Capability Of NGN• Inheriting Current Services

– Basic Voice Services– Supplementary Services– Intelligent Network Services

• NGN Value Added Services for Business Users – Basic Services of Centrex– Supplementary Services of Centrex

• Multimedia Application Services

• Value-added Services Integrating Internet

210

• Basic Voice Services– Voice Calls

• between local network users.• Automatic domestic and international direct long distance dialing• Calls from PBX extensions and to PBX console,

– Special services • including different kinds of queries and complaints

– Calls of mobile users in public networks

– Maintenance calls • for operators and maintainers

– Domestic and international fax

Service Capability Of NGN Inheriting Current Services

211


Inheriting Current Services − Supplementary Services

Abbreviated dialing Hotline Outgoing call barring Interception service Call forwarding Call back on busy Call waiting Conference calling Quota restricted calling

212

• Intelligent network Services

– Account card calling (ACC)– Free phone (FPH)– Virtual Private Network (VPN) – Televoting (VOT)– Universal personal telecommunications (UPT)– Premium Rate (PRM)– Credit card calling (CCC)– Universal Access Number (UAN)

Service Capability Of NGN Inheriting Current Services

213


• Inheriting Current Services – Basic Voice Services– Supplementary Services– Intelligent Network Services




214

• Developed for group users.

• Growing IP customer base

• Provides IP Centrex service for Centrex groups from one Softswitch domain.

• All basic services and supplementary services and a number of new services specialized

Service Capability Of NGN Value added Services for Business Users

215

• Basic Services of Centrex – Intra-group calling out

– Out-group calling out

– Intra-group calling in

– Out-group calling in

– Originating call screening

– Emergency call

– Distinctive ringing


216

• Supplementary Services of Centrex

– Designated pickup

– co-group pickup

– remotely set call forwarding unconditional

– remotely set call forwarding busy and remotely set call forwarding no reply


217






218

• Electronic whiteboard • Both parties can write and draw on the same

picture, • Remote teaching and technical exchange

• Content release • The contents of advertisements and media streams

can be released through a multimedia terminal • Instant messaging

• Allows real-time communication by means of text between one terminal user and another who has already logged in

Service Capability Of NGN Multimedia Application Services

219

• Video conferencing – Enterprises user may reserve or send a request for a

conference through Web, operator, or conference terminal.

– The Soft Switch or the operator directs MCU for video conferencing

• Video/Streaming/Web – to call or attend a conference at home or office. – The images, voice, slides, text talk, and file can be

sent to each participant synchronously.

Service Capability Of NGN Multimedia Application Services

220






221

• Click to Dial (CTD)– User sets up a voice or multimedia call through

the VoIP network by clicking a link / number on a Web page.

• Click to Fax (CTF)– User sends a fax to the called subscriber

through the VoIP network by clicking a link/ number on a Web page

Service Capability Of NGN Value Added Services-Integrating Internet

222

• Web 800– User calls the service / subscriber on the IP

network in which bill be paid by the called party. – Subscriber can click the 800 number in a Web page

or dial the 800 number to make a phone call.• UM service

– Combines a variety of media such as Email, Voice Mail, Voice, Video, SM, and Fax

– User receives Email , SM, Fax, Voice Mail and view dynamic images anywhere.


223

• IM service– Enables the mobile user, online user, and fixed user

to chat through multimedia through mobile, Internet, and fixed messages

– Collaboration allows business users to communicate via voice or text, thus implementing real-time services

• Colouring Ring-Back Tone (CRBT)– System will play back a pre-selected song or record

for the voice caller upon arrival of an incoming call to the callee


224

Soft PhoneIP Phone

MeetingServer MRS

PSTN/PLMN

PSTN Phone

SIP

Meeting Access No.: +852-28780999

Mobile Phone

Soft switch

Hong Kong

Singapore

UMG

PSTN PhoneIP Phone

UMGPSTN/PLMN

Meeting Access No.: +65-28780999

A meeting can be booked by phone or WEB Instant meeting and scheduled meeting are

provided Meeting service can be sold to group users

Packet network

Powerful tool for conference in NGN era


225

GUI or Web-based

client

• Intelligent call routing

• Unified message

• Voice mail

• Self-provisioning

Features

• Click to dial

• Click to conference

• Presence

• Address book


226

H323/SIP video terminal, OPENEYE softphone

Point to point, multi-point video conference which support instant call-

up and booking.

Support interconnect with H323 video network

Business meeting

Parents in hometown

Couples in different

sites

Remote education

OPENEYE SoftwarePC Softphone


http://cgi-ole/ageweb.pages?lang=ingles&face=fot&key1=F76-134196&key5=32427.84&key6=gal&lk=cgi-ole/ageweb.pages;lang=ingles@face=search@rand=83@query=mobile@page=1

227

INAP

3rd Party APP Server

Parlay API

SG

Soft switch

U-NICAAPP Server

U-NICAParlay Gateway

TELLIN SCP

SIP/INAPSIP/INAP

MRS

SIP

Service Openness Parlay API

Enable to introduce 3rd party service easily and quickly

INAP CS2

Standard IN service interface

Session Initial Protocol (SIP)

Access Application Server by SIP protocol

Open service system– flexible service creating

mode– quick service

deployment– open service interface


228

Softswitch

App ServerBilling center

iOSS

IP CoreIP Core

Corporate IP bar Resident

UMG

Voice services

Supplementary services

Fax

Internet

PPS

Voice mail

Triple Play

Services by PARLAY

Gateway services etc.

All the services

resident can enjoy.

Immediate

charging

Multi-media call

High speed

internet

Multi-media

configuration

Etc.

IP centrex

IP console

Video Comm.

LAN interconnection

High speed internet

Multi-media conf

One-line-multi-numbers

Service Capability Of NGN Value Added Services


Call Setup

229

Legacy Telephone Service

Basic Service: Call setupPhone number resolution

Call routing

Callee status detection

Resource reservation

Advanced Service: IN features and servicesAuthentication, admission and billing

Call rerouting, redirection, call-back and waiting

In-call application: IVR, call center, voice mail, centrix, and telephone vote

Advanced service provisioning and management based on user’s profile

230

Legacy Network Service Architecture

• Basic service is provided by distributed telephone switches– Call setup is executed in distributed telephone switches– A signaling network (SS7) interconnects the telephone

switches– Call procedures in the switches are interlinked by signaling

(TUP/ISUP)• Advanced service is offered by centralized Intelligent

Network– An advanced service formed by a service logic (SL) and a

serious of service independent blocks (SIB)– A management platform (SMP) supports service creation

and maintenance

231

Legacy Service Architecture

• Separate UNI services and network services• Make services independent of any call processing• Distributed call control and centralized services• One service control point for one service class• One service control point for one service instance• Decompose functions into small pieces and assembly

them together • Authentication, billing and routing are basis of any

services

232

2G MobilePSTN

• The PSTN/ISDN is based on 64 kbit/s digital connections, with a separate “common channel” signalling system• Access may be analogue (telephony), 64 kbit/s

digital (ISDN) or low speed digital (mobiles)• The network establishes an end-to-end digital

connection for the duration of each call• The PSTN/ISDN is designed for high reliability,

specified at the national level and connecting to form a global network

233

Legacy Service Architecture

Legacy Telecom Networks:Layer, Separate, Centralize and Sharing

PhysicalInterface

LogicalInterface

ServiceAccessPoint

Physical NetworkPhysical Network

Transmission NetworkTransmission Network

CPECPE CPECPE

Physical NetworkPhysical Network Physical NetworkPhysical Network

Transmission NetworkTransmission Network

Switching

Network

Switching

Network

Application

Layer

Service

Layer

Transmission

Layer

Physical

Layer

UNI UNI

NNI NNI

NNI

NNI NNI

Switching

Network

Switching

NetworkSwitching

Network

Switching

Network

Service

Network

Service

Network

234

Packet based Communication

• Best effort and service-independent packet-switching

network

• User-driven application/content-independent client-server

mode

• Smart terminal, servers and network

• Transparent active application access

• Open network, open application and open access

• Open and active services on the Internet

235

ISP“The Internet” (best-

endeavours network)

ISP

• The (public) Internet is based on the set of protocols defined by the Internet Engineering Task Force (IETF)• The primary protocol is the Internet Protocol (IP) which

describes a simple connectionless packet protocol able to operate over a range of media

• Other protocols work in association with the IP, for example, TCP to assist reliable end-to-end operation

• The Internet is defined by the Internet protocols rather than by a standardised architecture

• The Internet provides open interfaces, supporting rapid innovation

Packet based - Internet

236

Internet Service Architecture

Transmission

Network

Transmission

Network

Packet

Switching Network

Packet

Switching Network

ISP

Applications

ISP

Applications

CPECPE CPECPE

Transmission

Network

Transmission

NetworkTransmission

Network

Transmission

Network

Packet

Switching Network

Packet

Switching Network

ISP

Applications

ISP

ApplicationsISP

Applications

ISP

Applications

Application

Layer

Network

Layer

Transmission

Layer

PhysicalInterface

LogicalInterface

IP IPIP

NNI NNI

ServiceAccessPoint

APPAPP APPAPPServer Server Server

ServerClient

237

H.323 Architecture

H.323 Zone

H.323Terminal

H.323 Gatekeeper

H.323Gateway

PSTN

H.323Multipoint Control Unit

• Telco-centric multimedia,multiparty conferencing (initially for LANs)• Gatekeeper for network control, heavy-weight protocols• Widely deployed in first wave of VoIP standardization

3 stages of signaling:• RAS to Gatekeeper• H.225 call signaling• H.245 media stream control(can be simplified for VoIP)

238

SIP Based Services

• Internet-centric alternative, initially for large multicast conferences – SIP for call signaling, SDP (Session Description

Protocol) for media • Network servers for additional capabilities:

– Registrar for terminal registration, aliases– Redirect returns contact address directly to end user– Proxy forwards signaling (requests, responses)

• Evolution towards greater use of proxy/registrar for locating users, vertical services, call tracking, network control

239

SIP Call Setup

Shahab Irfan

Ptcl.net.pk ptcl.com

ProxyProxy

DNSLocation

server

Media Streams

INVITE

INVITE

Ringing

Ringing

200 OK

[email protected]

INVITE SDP proposes media type(s), IP & ports to send to

200 OK

200 OK SDP accepts/rejects media, gives IP & ports to send to

ACK

240

Where Do Services Live?

• Some implemented at the endpoints

– Last-number redial, call hold...

• Others may be better supported from the network

– Avoid need for PC or IP phone to be turned on (call forwarding)

– More complex services, such as conferencing

– Integration with web-based services (unified messaging)

• Example: SIP Proxy runs a script for each incoming call

– Parallel forking: forward INVITE to multiple endpoints simultaneously

– Sequential forking: try his office PC first, then lab, then cell phone, …

241

SIMPLE (SIP for IM and Presence)

PeterLinda

ptcl.net.pk ptcl.com

ProxyProxy

Presence server

Linda subscribes to notifications of changes in Peter’s status:Off-line, on-line, busy, away, available, ...

[email protected]

SUBSCRIBE

Update Presence

NOTIFY

NOTIFY

242

• Carrier networks consist of multiple domains

• each domain may have its own policies• each domain may have its own commercial goals• and possibly its own protocols & transport

Carrier Networks are not homogeneous

Domain 3

Domain 2Domain 1

ClientClient

Transport Network Transport Network

Service networkService network

ServiceDomain

ServiceDomain

Relevant interfaces

243

NGN: Service layer on IP, Current Status

• Support of multiple access networks (broadband and narrowband)

• Support of multiple access protocols (H.323, MGCP/MEGACO)

• Support session mobility control (MAP, Mobile IP, HLR/VLR)

• PSTN/IN interworking (ISUP, INAP, CAP, PINT, SPIRIT, SIP-T)

244

Current Approaches of NGN Service Architecture

• Mobile telephone network (GSM, GPRS)– Separation of Home network and serving network– Connection mobility and roaming control

• 3G-UMTS – Service portal and service capability feature (SCF)– Open Service Access (OSA)

• SIP– Distributed service control – Open access to services and applications

• Web Service (SOAP/WSFL/WSDL/UDDI)– Service access portal (SOAP)– Service description, discovery, and integration (UDDI)

245

ATerminal

ATerminal

B Terminal

B Terminal

APortal

BPortal

TransmissionTransmissionAccessAccess AccessAccess

Session ServiceSession Service

Control ServiceControl Service

A Home ServiceA Home Service B Home ServiceB Home ServiceA User Service Management

A User Service Management

B User ServiceManagement

B User ServiceManagement

TransmissionTransmissionAccess ServiceAccess Service Access ServiceAccess Service

TerminalTerminal TerminalTerminalTelecom basic service/call controlTelecom basic service/call control

Off-line customer managementOff-line customer management

Extended call control and IN chargingExtended call control and IN charging

Linear Service Architecture in Legacy Network: Static Services

Two-Dimension Service Architecture in NGN: Active Services

Changes of Telecom Service Architecture

246

NGN Soft switch: Services

• Legacy telephone service is static and close• Current soft switch experiences legacy

service architecture• Soft switch session is going to be distributed• Telecom service is becoming with 2-D

dynamic• Home service portal is to support open

service access• Service broker provides a platform for open

services

247

NGN Services Characteristics

• Multiple numbering systems • IP, Phone, Universal Numbers

• Distributed Intelligence• Databases in central servers, Provider database,

Customer PC, Phones• Central global database does inter-provider

translation

• Central Database is ‘shared’ by providers• Transaction volume

• At central db, number of inter-provider calls• At services databases (800, call-blocking lists, …)

number of subscribed services• At Provider and endpoints

248

NGN Services Characteristics cont’d

• Network Repositories • User data (profiles, lists) in multiple devices and

databases• Central Server provides reliability• Updates to devices synchronized on re-connect • Synchronization on demand or periodically:• User mobility

• Where should translation take place• Should cache migrate• Real-time constraints

• Transaction volume across devices, endpoints...

249

NGN Services Characteristics

• Object based services– Calls abstracted as object– Call models implemented within objects– Object mobility used to implement services

• Call forwarding• Third party call set-up

• Objects for service creation– Tool-kit for third party service creation– Base Objects/components upon which to build

• Device Independence– Migrate calls across device– Compose services across devices

250

End-to-End Connectivity?

There is no shortage of possible approaches – and they are all in use!

The problem– How to guarantee end-to-end service with the required QoS

across multiple networks using incompatible implementations[the subject of current international work]

251

Expected NGN Scope and Service Scope

252

Today’s Network Architectures

• Multiple, interworked, interdependent networks• Diversity of control and management architectures• Capacity and performance bottlenecks• Each network has its own control plane and management plane

• Multiple, interworked, interdependent networks• Diversity of control and management architectures• Capacity and performance bottlenecks• Each network has its own control plane and management plane

IP/MPLSNetworks

PSTN/ISDN

Radio Access

Networks

EthernetNetworks

Wireless Access

Frame Relay

Networks

IWF

IWF

IWF

IWF

IWF

IWF

IWF

ATM Networks

IWF

IWF

253

Near Term Evolution

ATM Networks

IWF

PSTN/ISDN Rec. Q.2931, PNNI

Frame Relay

Networks

IP-based Networks

PSTN/ISDN OSF & NM, M series Rec.

Rec. Y.1310

IETF RFCs

Q & X series Rec.

IWF

IWF

Rec. I.555Rec. I.580

Rec. Q.931

ATM OSF & NM, M series Rec.

SNMP based

FR OSF & NM

OSF = Operating Support Function

For• Convergence on ATM core networking enables initial stage

of unified management and control• Enhanced performance and QoS capabilities for multi-

services over common platform

For• Convergence on ATM core networking enables initial stage

of unified management and control• Enhanced performance and QoS capabilities for multi-

services over common platform

PSTN/ISDN

IWF

SS7 Network

Rec. I.580Rec. Q.700 series

Against• Lack of service transparency between IP

based services and ATM/PSTN services

Against• Lack of service transparency between IP

based services and ATM/PSTN services

Wireless access

IWF

254

Full-term - Convergence on IP/MPLS Core

• Requires well defined interworking mechanism for all services• Transfer plane functions• Control plane functions• Management plane functions

• Requires well defined interworking mechanism for all services• Transfer plane functions• Control plane functions• Management plane functions

IP/MPLS NETWORK

ATMNetworks

Frame Relay

Networks

Frame Relay

Networks

IWF EthernetNetworks

EthernetNetworks

ATM Networks

Label Switching Router (LSR) Label Switched Path (LSP)

IWF IWF

IWF

IWFIWF

255

Recommended practical/lab work on NGN

256

• To connect different Media Gateways like IAD, AGW, MGW, UMG etc with subscriber end

• To configure different MGWs mentioned above with IP core network by using basic commands

• To test the Network connectivity and to identify the fault points on the Network by using commands like ping, tracert etc

• To learn creation of a terminal user and querying the existing user and displaying other terminals

• Learning the addition and removal of particular board/frame of media gateways by using basic commands of Board Management/Frame Management etc

• Adding and removing the IP address of a particular interface on a particular board

257

Recommended practical/lab work on NGN

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