Cellular Networking Perspectives

Wireless, Telecom and Computer Glossary

Are there wireless telecommunications (or network or security) terms or acronyms that you keep hearing, but that whose meanings are unclear to you? Your prayers have been answered. Check this alphabetic list of 2051 wireless telecom terms, including many data networking and security terms as well. If the term you are looking for is not listed, please suggest it to us. We will define it for you, and add it to this list for the benefit of other readers, also.

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0-9 10 Base-T Basic Ethernet at 10 Mbit/sec

100 Base-T Ethernet running at 100 Mbit/sec

1000 Base-T Ethernet running at 1,000 Mbit/sec

128QAM QAM with 7 bits per symbol.

16QAM QAM with 4 bits per symbol.

1G First Generation. Refers to analog cellular systems

1x A cdma2000 notation that indicates that one carrier is being used. Compare with 3x

1xEVDO See EvDO

1xEVDV See EVDV

1XRTT cdma2000 operating mode at basic chip rate (1.2288 Mcps). The theoretical top speed is 153 kbps

2G Second Generation. Refers to digital cellular and PCS wireless systems oriented to voice and low speed data services

2R Receive, Reshape (an optical signal). See 3R

32QAM QAM with 5 bits per symbol.

3G Third Generation. Refers to the next generation of wireless systems - digital with high speed data. Being standardized by 3GPP and 3GPP2

3GiA 3G Internet Appliance

3GPP 3rd Generation Partnership Project for W-CDMA (GSM)

3GPP2 3rd Generation Partnership Project for cdma2000

3GSP 3G Service Provider

3R Reshaping, Retiming, Reamplifying (an optical signal). See 2R

3WC Three Way Call

3x A cdma2000 notation that indicates that three carriers are being used. Compare with 1x. Not widely implemented. Although this allows higher maximum speeds, the average speed per user will not change significantly

3XRTT cdma2000 operating mode at 3 times the basic chip rate of 1.2288 Mcps

64QAM QAM with 6 bits per symbol.

802.11 An IEEE committee that standardizes a wireless Ethernet replacement technology in the ISM band. 802.11b is most commonly implemented and runs at approximately 10 Mbps in the 2.4GHz band. 802.11a runs

at 54 Mbps in the 5 GHz band. 802.11g provides 24 Mbps in the same band as 802.11b.

802.11a A WiFi WLAN variant that is higher speed (54 Mbps) than 802.11b. Because it also operates in a different frequency band it has proven less popular than 802.11g which offers higher speed in the same band as 802.11b thus providing a simpler migration strategy. The range of this protocol is also lower and the LOS requirements more stringent. See ADRC

802.11b IEEE Wireless LAN system providing throughput of about 11 Mbps but see ADRC

802.11c An IEEE standard for network interoperability between WLAN protocols

802.11d An IEEE standard for operation of their WLAN protocols outside the normal frequency bands (e.g. due to the unavailability of those bands in some countries)

802.11e An IEEE standard for QoS in their WLAN protocols 802.11a, 802.11b, 802.11g and 802.11n

802.11f An IEEE standard for interconnection between wireless APs

802.11g A second generation version of WiFi providing 54 Mbps raw throughput (typically a user data rate of about half that) in the same 2.4 GHz frequency band as 802.11b. This gave it an advantage over 802.11a which had similar performance but operated in a different frequency band.

802.11h An IEEE standard for spectrum and transmit power management for their WLAN protocols

802.11i Enhanced security for IEEE WLAN protocols

802.11j An adaptation of 802.11 WLAN protocols to the Japanese 4.9–5 GHz frequency band

802.11k A proposed IEEE standard for RRM

802.11m A group for editorial maintenance of IEEE 802.11 WLAN standards

802.11n A future IEEE WLAN protocol that promises raw data rates of 540 Mbps in either the 2.4 GHz or 5 GHz band and thus will likely eventually replace 802.11a, 802.11b and 802.11g. The protocol is scheduled for completion in 2009. See EWC

802.11p A proposed IEEE standard for ITS. Also known as WAVE

802.11r A proposed IEEE standard for handoff between APs

802.11s A proposed IEEE standard for mesh networking

802.11t A proposed test specification for IEEE WLAN standards

802.11u A proposed standard for authorization of users on IEEE WLANs

802.11v A proposed wireless network management standard for IEEE WLAN protocols

802.11w A proposed standard for the protection of system management

information in IEEE WLAN protocols

802.11y A proposed standard for operation of IEEE WLAN protocols in the 3.65-3.7 GHz frequency band

802.15 See Bluetooth

802.16 IEEE WiMax radio interface.

802.3 IEEE standard for Ethernet

8PSK PSK with 8 states, allowing the coding of 8 bit combinations. It is used in EDGE.

8QAM QAM with 3 bits per symbol.

911 The ES service code in many parts of the United States, Canada and a few other countries.

A A(2) An IP host address

A-bis Interface between BTS and BSC

A-GPS Assisted GPS. Network provides information to mobile device to acquire satellite signals and may assist with processing of received data

A-interface Interface between the MSC and BS

A-Key The primary CAVE authentication key, used to generate SSD

A/D Analog/Digital. Usually used in the context of conversion from analog to digital (or vice-versa)

A3 GSM authentication algorithm

A5 GSM data encryption algorithm

A5/3 An encryption algorithm for GSM and EDGE

A8 GSM voice encryption algorithm. Used to generate Kc

AAA Authentication, Authorization and Accounting entity. See RADIUS and Diameter

AAL AAL Adaptation Layer

ABNF Augmented BNF. Defined in RFC 2234

ABR Average bit rate

ABS Alternate Billing Service

AC Authentication Centre. Stores information for authenticating mobiles, and encrypting their voice and data transmissions

ACC Analog Control Channel. See FSK

ACCM Asynchronous Control Character Map

ACCOLC Access Overload Class

ACCT CDMA Access Control by Call Type

ACD Automatic Call Distributor. Distributes incoming calls to one of a number of people equally able to handle them (e.g. for customer

service)

ACELP(1) Adaptive CELP

ACELP(2) Algebraic CELP

ACF Authentication Control Function

ACG Automatic Code Gapping. A method of shedding load in telecommunications systems

ACH Access Channel

ACK Acknowledgement signal

ACLR Adjacent Channel Leakage Ratio. The ratio of the on-channel transmit power to the power measured in one of the adjacent channels. An important W-CDMA parameter.

ACM SS7 ISUP Address Complete message. Response to IAM

ACP Adjacent Channel Power

ACRE Authorization & Call Routing Equipment. Used for routing calls to cellular phones with a ‘cordless’ mode

AD(1) Abbreviated Dialing

AD(2) Architecture Document

ADA Advertising Agent. Provides information to a MS on the services provided by a 3G network

ADDS Application Data Delivery Service. See SMS

Adjacent Channel Interference

Interference from signals at slightly different frequencies

ADN Abbreviated Dialing Numbers

ADPCM Adaptive Differential PCM

ADRC Aggregate Data Rate Caveat. A warning that most wireless data rates are aggregate, meaning that all users share the bandwidth, and often they are raw rates higher than the actual user throughput could ever be even on an unloaded system. It is probably good to start by dividing the raw rate by a factor of two to obtain the total user throughput rate and then further divide by the average number of simultaneous users (not connected users, but the number who are likely to be simultaneously transmitting)

ADS Asynchronous Data Service

ADSL Asymmetric DSL. Bit rates are higher from the network than from the client

AdSpec IETF Advertisement Specification

AEG Asian Expert Group. A WAP Working Group

AES Audio Engineering Society

AF Application Function.

AFLT Advanced Forward Link Trilateration. A geolocation technique that

utilizes the mobile station’s measured time of arrival of radio signals from the base stations (and, possibly, other terrestrial measurements)

AFRCN GSM Absolute radio frequency channel number

AFSK Audio FSK. Communication by changing frequencies in the audio band rather than RF. Used by MF, DTMF

AGCH GSM Access Grant Channel. The traffic channel assignment information is sent to the mobile on this channel.

AGPS Network Assisted GPS. Land station assists mobile in acquiring its position

AGW Access Gateway

AH(1) Authentication Header

AH(2) Answer Hold. Service that allows an incoming call to be placed on hold without answering it first. Closely related to USCF

AHAG TIA TR-45 ad hoc Authentication Group

AI Air Interface

AICH Acquisition Indicator Channel

AIN Advanced Intelligent Network. Telcordia version of IN

Air Interface Synonym for Radio Interface.

AK Anonymity Key. In AKA it is derived from RAND using f5.

AKA Authentication and Key Agreement. New generation of security being developed for 3GPP2 CDMA systems and 3GPP UMTS systems. Parts may also be applied to GSM

Alert A command to a mobile to notify the user of an incoming call or message

ALI Automatic Location Information. A database that contains information about the location of emergency callers

AM Amplitude Modulation. See FM

AMA Automatic Message Accounting. See CDR

AMF AKA Authentication Management Field. May indicate the algorithm and key used by the current authentication system.

AMI Alternate Mark Inversion

AMPS Advanced Mobile Phone Service. TIA analog cellular, and all standards that retain compatibility with it (NAMPS, D-AMPS, CDMA). Standardized in EIA/TIA-553

AMR Adaptive MultiRate Voice Coder. Proposed for use in GSM and UMTS. Bit rates vary between 12.2 and 4.75 kbps

AMR-WB AMR wide (audio) band Voice Coder chosen for UMTS. Developed by Nokia and Voiceage. Has 9 different bitrates

AMTA American Mobile Telecommunications Association

AN Access Network

analog Transmission of information through a continuously variable signal.

Compare with digital

analogue Alternate (British) spelling of analog

Anchor MSC The first MSC involved in a wireless call

ANI(1) Automatic Number Identification. Provision of charge number during a call to allow toll calls without operator intervention

ANI(2) Access Network Identifier

ANI II ANI Information Digits. Describes the type of phone being used to call (e.g. residential line or payphone).

ANM SS7 ISUP Answer Message

ANSI American National Standards Institute

ANSI-136 ANSI version of the TDMA air interface standard. Replaces IS-136. Correct name is TIA-136

ANSI-41 See TIA/EIA-41

ANT ADSL Network Termination

AOA Angle of Arrival. A technique for locating a radio by estimating the angle of signal arrival at multiple points. Compare with TOA

AoC Advice of Charge

AP(1) Application Part (of a protocol)

AP(2) Access Point. An 802.11 BS

APCO Association of Public Safety Communications Officials

APDU Application PDU

API Application Programming Interface

APLMN Associated PLMN

APM Application Transport

APMN Associated PMN

APN Access Point Name. In a GPRS network, the domain name referring to an external packet network

ARCH Access Response Channel

ARIB Association of Radio Industries and Businesses. Responsible for standardization of telecommunications protocols in Japan

ARM ARQ Response Mode

ARP(1) Authorized Receipt Point. The sole entity authorized to settle and exchange roamer charges and revenue for a carrier

ARP(2) IETF Address Resolution Protocol. Binds the physical (MAC) address of a device to an IP address on a local network (e.g. ethernet subnet).

ARPU Average Revenue Per User/Unit

ARQ Automatic Repeat Request. A method of error correction where the receiver detects errors, and requests retransmission from the sender.

AS Internet Application Server. Handles applications for a range of addresses (e.g. a telephone switch)

ASCII American Standard Code for Information Interchange. The most commonly used method for encoding text in 8 bit characters. See UNICODE for more complex alphabets and the obsolete EBCDIC

ASE Application Service Element

ASIC Application Specific Integrated Circuit. A computer chip that is customized for a special purpose application

ASN.1 Abstract Syntax Notation 1. A formal, textual, representation of a protocol message set

ASP AS Process

ASR Automatic Speech Recognition

Asynchronous Data is transmitted only when needed. At least one bit is needed to indicate the start of transmission (known as a start bit). Compare with Synchronous

AT Access Tandem. A switch that can be used to reach a variety of IXCs

ATI Access Terminal Identifier

ATIS Alliance for Telecommunications Industry Solutions. Parent organization for the T1 standards committees and many telecom industry groups, such as OBF

ATM Asynchronous Transfer Mode. Transmits data as 53 byte units using a connection-oriented protocol at speeds up to 2.488 Gbps

ATP Access Transport Parameter (also Adenosine Tri-Phosphate :)

ATS Abstract Test Suite

AuC GSM term for AC

AUTH An OMT bit that turns mobile authentication on or off for all mobiles within a cell

AUTHBS Authentication Response from the BS

Authentication Proving the identity of an individual or application (e.g. MS)

Authentication Enhancements

Improvements to network based authentication (TIA/EIA-41) defined in IS-778

Authentication Vector

See Quintet and Triplet

AUTHR Authentication Response. The output of CAVE when RAND is used as a global challenge

AUTHU Authentication Response to Unique Challenge

AUTN AKA Network Authentication Token. Composed of SQN (concealed), AMF and MAC

AV Authentication Vector

AVC Analog Voice Channel

AVP Attribute Value Pair. A method of encoding parameters that includes the length of the data, the attribute (parameter) type (usually fixed length) and the attribute value. cf TLV

AWGN Additive White Gaussian Noise

AWI Alert with Information; used to transmit data while alerting an MS

AWS An FCC term for IMTS-2000

B B-SMS Broadcast SMS

B/I Busy/Idle bit

B8ZS Bipolar with 8 Zero Substitution. Replaces an all-0 octet by one containing two BPV

Baby Bell see RBOC

Backhaul Routing trunks from a cellsite to an MSC before routing to the PSTN.

badput A cute name for wasted bandwidth. Bandwidth = goodput(throughput) + badput + unused bandwidth

BAF Billing Automatic Message Accounting Format. The CDR/AMA format used by most US wireline telecom carriers

BAIC Barring of All Incoming Calls

BAOC Barring of All Outgoing Calls

BARG GSMA Billing, Accounting and Roaming Group

Barring Refusal to allow certain types of calls

Baseband The signal(s) used to modulate the radio channel in the transmitter, and which are recovered by the receiver by demodulating the received radio channel.

BATS Broadcast Air-interface Transport Service used by TIA/EIA-136

BBIT Best Breakfast In Town.

BCCH Broadcast Control Channel

BCD Binary Coded Decimal. Digits 0-9 are encoded as 4 bit numbers (nibble), so two fit within a byte. See TBCD

BCE Base Station Central Equipment. See BSC

BCH(1) Broadcast Channel. A channel transmitted by one (e.g. BS) and received by many (e.g. MS)

BCH(2) Bose, Chaudhuri, and Hocquengham error detection and correction methodology

BCH(3) Basic Call Handling

BCM Basic Call Manager. See WIN

BCMCS Broadcast/Multicast Services for 3GPP2. Contrast with BMC

BCSM Basic Call State Model. A n IN concept

BD Billing Domain

BDN Barred Dialing Number

Bearer capability

A capability of a transport protocol (e.g. a maximum bitrate or message latency). A Teleservice may be able to use any facility that

can provide a specified bearer capability.

BEG Billing Expert Group. A WAP Working Group

BER(1) See Bit Error Rate

BER(2) Basic Encoding Rules. See ASN.1

BGCF Breakout Gateway Control Function. Controls the assignment of resources to IMS sessions in a serving system. Connected to the S-CSCF, MGCF and BGCF

BGP Border Gateway Protocol of IETF RFC 1771. See EBGP.

BIB Backward Indicator Bit. Indicates when a received MTP frame is out of sequence. See FIB

BIC-Roam Barring of Incoming Calls while Roaming

BICC Bearer Independent Call Control. ISUP adapted for use over IP-based transport. Compare with SIP

BID A SID allocated for accounting purposes. BID's are allocated by Cibernet

BISDN Broadband ISDN

bit Fundamental unit of information, occupying two discrete states (e.g. 0 or 1)

Bit Error Rate The fraction of binary bits that are received with the wrong value.

BLA SS7 ISUP Blocking acknowledgement. See BLO

BLOB Block of Bits

Bluetooth A cable-replacement radio protocol for short distance (5-100 meter) networking at moderate speeds (1 Mbps raw bandwidth for version 1 and 3 Mbps for version 2). Developed by the Bluetooth Consortium and standardized by IEEE 802.15.1

BLV Busy Line Verification

BM-SC Broadcast/Multicast Service Center

BMC Broadcast Multicast Control. See 3GPP TS25.324. Contrast with BCMCS.

BMI BS, MSC and Interworking function

BNF Backus-Naur Form. A precursor to ASN.1 and other meta-language

BNS Billed Number Screening

BOC Bell Operating Company

BOIC Barring of Outgoing International Calls

BOIC-exHC BOIC except to HC

Border Router An IP Router that connects to routers in other networks using the EBGP protocol.

BP Bit Position

bps Bits per second. A measure of the speed of a transmission link

BPSK Biphase Shift Keying

BPV Bi-Polar Violation. Transmission of two one-bits in a PCM channel (e.g. DS0) with the same polarity (e.g. both positive or both negative). May be deliberately used to indicate all-zero octets. See B8ZS and HDB3

BR Border Router. Connects a CN with peer networks

BREW Binary Runtime for Wireless

BRI Basic Rate Interface (64 kbps). See DS0

Broadcast SMS Short messages sent to multiple mobiles in multiple cells, requiring only one message per cell

BS Base Station (includes BTS and BSC)

BSC Base Station Controller. The 'brains' of a base station, controlling the radio equipment in the BTS

BSF Bootstrapping Function

BSIC BS Identity Code. Color code used by GSM systems to ensure that the source of a frequency transmission can be identified, in areas where multiple cells transmitting on the same frequency can be received

BSMC Base Station Manufacturer Code

BSN(1) Backward Sequence Number. The sequence number of the last correctly received MTP frame received. Contrast with FSN

BSN(2) BCMCS Serving Node

BSS(1) BS Subsystem

BSS(2) Basic Service Set. An 802.11 network.

BSSMAP GSM BSS MAP

BT Burst Type

BTA Basic Trading Area

BTS Base Transceiver System (radio portion of BS)

BTTC Broadcast SMS

BWIF Broadband Wireless Internet Forum. A program of IEEE-ISTO

BXA US DoC Bureau of Export Administration. Administers EAR

byte An 8 bit unit of data storage. See octet

C C-PDS cdma2000 Packet Data Service

C/I Carrier to Interference Ratio

C7 See CCS7

CA(1) Certificate/Certification Authority

CA(2) Collision Avoidance

CAC Carrier Access Code. Identifies a long distance carrier. 101+CIC

CALEA US Communications Assistance for Law Enforcement law. Requires that telecommunications carriers provide for surveillance (aka

wiretaps) at the switch site

CAMA Centralized Automatic Message Accounting

CAMEL Customized Applications for Mobile Networks Enhanced Logic based on CAP. IN capabilities for GSM. Compare with WIN

Candidate MSC An MSC being considered as the Target MSC of a handoff

CANID Current ANI

CAP(1) CAMEL AP

CAP(2) Carrierless Amplitude and Phase modulation

CAP(3) Competitive Access Provider

CAPCS Cellular Auxiliary Personal Communications Service

CAR Committed Access Rate. An IP method to achieve higher QoS

CARE Customer Account Record Exchange. Sent from a LEC to an IXC to establish a long distance account for a customer

Care-of Address

The address that a Home Agent forwards packets to for handling by the Foreign Agent in MIP

Carnivore US FBI ISP wiretapping box, including a processor and removable hard drive to capture internet sessions (email, web access etc.).

CAS Call Associated Signaling. See ISUP. Contrast with NCAS

CAT Smart Card Application Toolkit

CATPT CDMA UIM Card Application Toolkit Protocol Teleservice

CAVE TIA Cellular Authentication and Voice Encryption Algorithm

CB Cell Broadcast

CBC CB Center

CBMI CB Message Identifier

CBR Constant Bit Rate

CBS GSM/W-CDMA Cell Broadcast SMS

CC(1) E.164 Country Code

CC(2) GSM Call Control protocol

CC(3) Content of Communications (for LAES)

CCA Common Cryptographic Algorithm

CCAT CDMA Card Application Toolkit. Specifies communications between a CDMA R-UIM and the ME

CCB US FCC Common Carrier Bureau

CCBS Call Completion to Busy Subscriber

CCCH GSM Common Control Channels – PCH, RACH, AGCH

CCF(1) Call Control Function (IN term)

CCF(2) Charging Collection Function (3GPP)

CCH Control Channel

CCITT International Telegraph and Telephone Consultative Committee.

Precursor to ITU. See ITU-T and ITU-R

CCNR Call Completion on No Reply. See CFNA

CCP Compression Control Protocol

CCPD Common Channel Packet Data

CCPN Call Completion to a Ported Number. See LNP

CCR(1) SS7 ISUP Continuity check request

CCR(2) Class Conformance Requirement

CCS Common Channel Signaling

CCS7 ITU-T version of SS7

CCSA China Communications Standards Association. Successor to CWTS.

CCSC Cellular Carrier Specific Code (e.g. #123)

CCSH CDMA Code Combining Soft Handoff

CCSS Call Completion Service Setup

CCT Circuit

CCV Credit Card Validation

CCW Cancel Call Waiting

CD Collision Detection

CDATA Character Data, such as a quoted text string. Used in XML and derivative protocols such as WML

CDCP Call Detail Collection Point. See TIA/EIA-124

CDG CDMA Development Group

CDGP Call Detail Generation Point

CDIS Call Detail Information Source. An MSC or other entity that produces proprietary CDR’s

CDMA Code Division Multiple Access. Implemented in AMPS-compatible systems by IS-95. Also see W-CDMA

CDMA-PAMR A CDMA-based PAMR system.

cdma2000 Trade name for CDMA air interface standards aimed at 3G requirements, including IS-2000. It operates in 1.25 MHz carriers at 1.2288 Mcps. There is some debate about whether the "CDMA" should be upper or lower case :)

cdmaOne Trade name for first generations of CDMA air interface standards, including TIA/EIA-95. Operates in pairs of 1.25 MHz channels

CdPA Called Party Address

CDPD Cellular Digital Packet Data. A protocol that uses 30 khz AMPS channels to transmit packets of data. Standardized in TIA/EIA/IS-732

CdPN Called Party Number. The DN of the party receiving a call

CDR Charging Data Record or Call Detail Record

CDRP Call Detail Rating Point

CDVCC Coded Digital Verification Color Code

CEASA Cellular Emergency Alert Systems Association. Promotes the use of emergency alerts over cell phones.

CEG Carrier Expert Group. A WAP Working Group

cell The coverage area of a single radio cellsite or sector in a cellular or PCS system

cellular A radio concept that allows the multiplication of capacity by using many low-power cell to cover an area, reusing frequencies as much as possible

CELP Code Excited Linear Prediction

CENELEC European Committee for Electrotechnical Standardization

CEP Cell Equipment Processor

CEPT Conference des administrations Europeannes des Postes et Telecommunications

CEWS Cell Work Station. Software running here supports termination of the LAPD links to the BTS. A minimal OA&M application is included to support maintenance of the A-bis interface processes and to route OA&M messages to/from the BTS. Call Handling software derives directly from the CEP and PPP of the BCE.

CF Collection function. LEA that collects J-STD-025 data

CFB Call Forwarding when subscribing telephone is busy

CFNA Call forward on no-answer (and, usually, also on no page response). See CFNRc and CFNRy

CFNRc Call forward when mobile not reachable. See CFNA

CFNRy Call forward when mobile is not answered. See CFNA

CFU Call Forwarding Unconditional (i.e. every incoming call will be forwarded)

CG Charging Gateway

CGB SS7 ISUP Circuit group blocking

CGBA SS7 ISUP CGB acknowledgement

CGI(1) Common Gateway Interface

CGI(2) GSM Cell Global Identification. Composed of LAI + CI

CGL Calling Geodetic Location. The position of a mobile phone, as transmitted through various signaling protocols. See GAD

CGLP SS7 ISUP Calling Geodetic Location Parameter (i.e. Latitude and Longitude)

CgPN Calling Party Number. The DN of the party initiating a call

CGSA Cellular Geographic Serving Area. MSA or RSA

CGU SS7 ISUP Circuit group unblocking

CGUA SS7 ISUP CGU acknowledgement

CGVoP Carrier Grade Voice over Packet. See VoIP

CHAP PPP Challenge Handshake Authentication Protocol. Use of RADIUS to authenticate a terminal without sending security data in the clear. Compare with PAP

cHTML Compact HTML. Use by iMode. See also WML and XHTML

Churn The rate at which subscribers leave one wireless carrier to go to another. A major expense for carriers

CI GSM Cell Identity. A 16 bit number identifying a cell within an LAI

CIBER Cellular Intercarrier Billing Exchange Record. Format used for exchange of wireless billing records. Maintained by Cibernet Corp

Cibernet A subsidiary of the CTIA responsible for facilitating billing aspects of roaming

CIC Carrier Identification Code. See CAC

Ciphertext Encrypted data. Compare with Plaintext

CIR(1) Synonym for C/I

CIR(2) Committed Information Rate. Bandwidth associated with a frame relay PVC

Circuit-switched data

Data transmitted over a dedicated (although usually virtual) channel. The destinatioin address is implicitly defined by the (virtual) circuit that is selected

CISC CRTC Interconnection Steering Committee

CITEL Commission InterAmericanna de Telecommunications Association. A Latin American telecommunications association

CK Cipher Key. In AKA, it is derived from RAND using f3 and applied to traffic using f8

CKSN CK Sequence Number

CLASS Custom Local Area Signaling Services. A package of features offered by wireline carriers

Clearinghouse A central point for the gathering and redistribution of records, such as billing records

CLEC Competitive LEC. A new entrant in a market previously limited to one carrier. Some wireless carriers may qualify for this designation

CLI Calling Line Identity. See CgPN

CLIP Calling Line Identification Presentation. See CNIP

CLIR Calling Line Identification Restriction. See CNIR

CLLI Common Language Location Identifier. An ASCII identifier of a telephone switch or calling area.

CLNP Connectionless Network Protocol

CLNS Connectionless Network Service

CM GSM Connection Management

CMAC Control Mobile Attenuation Code

CMC Cellular Mobile Carrier. A generic term used to classify carrier class

cellular systems

CMEA Cellular MEA. Based on CAVE

CMIP Common Management Information Protocol

CMRS Commercial Mobile Radio Service

CMSP Indian GSM licence. Replaced by UASL.

CMT Cellular messaging teleservice. A service based on SMS that is similar to that provided by alphanumeric pagers

CMWN Cancel Message Waiting Notification

CN Core Network. Protocols for this include GSM MAP and ANSI-41

CNA Canadian Number Administrator. Administers telecom numbering resources in Canada, under the oversight of the CRTC.

CNAME Canonical Name. A basic Domain name that may be pointed to by multiple aliases

CNAP Calling NAme Presentation. A terminating party feature. Overridden by CNAR

CNAR Calling NAme Restriction. An originating party feature

CNDB Calling Name Database

CNIP Calling Number Identification Presentation. A terminating party feature. Overridden by CNIR

CNIR Calling Number Identification Restriction. An originating party feature

CO Central Office

Co-channel Interference

Interference from other signals using the same radio channel

COA Care-Of Address

codec Voice coder and decoder. See vocoder and Voice Coder

COFDM Code OFDMA

COFETEL Comision Federal de Telecomunicaciones de Mexico

COLP Connected Line Identification Presentation. See COLR, CNIP

COLR Connected Line Identification Restriction. See CNIR, COLP

COMET IETF SIP Preconditions Met message

Confidentiality Keeping information private (e.g. by encryption)

CONS Connection-Oriented Network Service

Control Channel

A cellular or PCS channel that broadcasts information about a cell to mobiles that are not currently in a call

CORBA Common Object Request Broker Architecture

CORD Cellular Operations Record Distribution

CoS Class of Service. Method of managing traffic by grouping similar types (e.g. voice, video, email)

COUNT Call History Count. An internal mobile counter that can be used to detect the presence of clones

COWS Common Work Station. Software running in the Common Work Station element supports termination of the SS7 links to the MSC as well as the X.25 links to the OMC (including the OSI stack) and any PSDN services. The majority of the OA&M software is found here.

CPDE Centralized PDE

CPE Customer Premises Equipment. A standard telephone is an example of telecommunications equipment that is usually located at the customer’s site.

CPG SS7 ISUP Call ProGress Message

CPGA Cost per Gross Addition. The cost to a carrier of adding one subscriber

CPL IETF Call Processing Language. An XML-based language for describing internet telecommunications services.

CPN See CgPN

CPP Calling Party Pays. The calling party pays for calls to mobile, not the mobile receiving the call. cf TPP

CQM(1) Channel Quality Measurement

CQM(2) Core Quality of Service Manager. Obsolete. See PDF

CR Change Request. A description of a problem in a standard (error, limitation, ambiguity or restriction) and a description of how it should be fixed

CR-LDP Constraint-based Routing LDP. See MPLS

CRC Cyclic Redundancy Code (or check). Included in many digital protocols to check for errors in transmitted messages

CRDB Coordinate Routing DataBase. Proposed for E911 systems to convert a location into routing information

CRL Certificate Revocation List

CRM(1) Customer Resource Management

CRM(2) Channel Request Message

CRTC Canadian Radio-television and Telecommunications Commission

CRTP Compressed Real-Time Transport Protocol. Provides compression (and decompression) of RTP, UDP and IP headers.

Cryptosync Externally-provided synchronizing information for cryptoalgorithms (ciphers) that allows an encryptor at one end to uniquely encrypt each block of content into ciphertext, and yet allows a decryptor at the other end to properly decrypt the ciphertext to yield the original plaintext. Cryptosync often takes the form of the output of a binary counter

CS(1) IN Capability Set

CS(2) Circuit switched. Contrast with PS

CS-1 IN CS 1

CS-2 IN Capability Set 2

CS-ACELP Conjugate Structure ACELP

CSA Canadian Standards Association

CSC Customer Service Center

CSCF Call Session Control Function. Controls the assignment of resources from the home system. See I-CSCF, P-CSCF and S-CSCF

CSCN Canadian Steering Committee on Numbering. A working group of the CRTC CISC

CSD Circuit switched data. Data travels between two devices using a fixed amount of bandwidth allocated for the duration of the data call. Compare with Packet data that uses shared bandwidth to service multiple users. Packet data can be more efficient (except when the overhead of identifying and routing packets is greater than the savings) but the performance is less predictable.

CSFP Coded Superframe Phase

CSI CAMEL Subscription Information

CSMA Carrier Sense Multiple Access

CSMA/CA See CSMA/CD

CSMA/CD CSMA with CD (also known as CA). Ethernet devices use this to minimize collisions by checking the line before sending

CSRC Contributing Source

CSS Cascading Style Sheets. See HTML

CSU Channel Service Unit. Unit that interfaces between the telephone company and a private network

CT Call Transfer

CTCP Compressed TCP. Provides compression (and decompression) of TCP and IP headers.

CTIA Cellular Telecommunications Industry Association

CUG Closed User Group. Calls are restricted to within the group

CW Calling Waiting

CWTA Canadian Wireless Telecommunications Association

CWTS Chinese Wireless Telecommunications Standards. Replaced by CCSA

D D Digit The fourth digit of an NANP phone number. Currently restricted to the

values 2-9 to allow 7 digit dialing

D-AMPS Digital AMPS (IS-54 and IS-136 TDMA)

D-H Diffie-Hellman

D/L Downlink (e.g. from base station to mobile). Compare with U/L.

DACS See DCS

DAP X.500 Directory Access protocol

DataTAC Data TAC. A Motorola wireless data system. Formerly known as Ardis.

dB Decibel. 10 times the logarithm of the value in base 10

dBi Decibels relative to isotropic radiator. A measurement of the gain of an antenna.

dBm Decibels referenced to one milliwatt

DCC Digital Color Code. A number assigned to a control channel used to limit erroneous accesses

DCCH Digital Control Channel. The control channel used by IS-136 and TIA/EIA-136 D-AMPS systems

DCE Data Communications Equipment (i.e. a computer)

DCF DRM Content Format

DCH Dedicated Channel

DCN Data Communications Network

DCS(1) Data Coding Scheme

DCS(2) Digital Cross-Connect System

DCS(3) European PCS frequencies in the 1800 MHz range.

DDM Data Description Method

DEA US Drug Enforcement Agency

DECT Digital Enhanced Cordless Telephony

DES Data Encryption Standard. A commonly used encryption method, usually used with 56 bit keys. See AES, TDES.

DF(1) UIM Dedicated File. Compare with EF and MF

DF(2) Delivery Function (for LAES)

DFCA Dynamic Frequency and Channel Allocation. Dynamic assignment of radio channels to optimize capacity. Proposed for GSM, but not yet implemented.

DFP Distributed Functional Plane NRM

DHCP Dynamic Host Control Protocol. Allows automatic assignment of IP addresses on a network

DHKE Diffie-Hellman Key Exchange. A method of securely exchange encryption keys over an insecure interface

Diameter An IETF AAA protocol designed to be twice as good as RADIUS. Unlike its predecessor it supports MIP and uses SCTP (or TCP) instead of UDP for more reliable transport. It uses IPSEC and TLS instead of a shared secret.

DID Direct Inward Dialing. Directs all calls to a block of numbers to a PBX

Diffie-Hellman A secure key exchange mechanism

Diffserv Differentiated Services. Different QoS for different types of traffic (e.g. voice, video, email). See IETF RFCs 2474 and 2475

digital Transmission of information through a signal that can take on only certain discrete values (e.g. bits with values 0 or 1). Compare with analog

Disconnection The end of a call. Not to be confused with Termination of a call or the Release of a trunk

DL Downlink. Radio link from network ‘down’ to terminal. Compare with UL

DLC Digital Loop Carrier. A single digital facility (e.g. T1 or T3) carrying multiple lines to a business or other large customer

DLCI Data Link Connection/Circuit Identifier

DLP Discrete Logarithm Problem. Used in some cryptography systems

DMAC Digital Mobile Attenuation Code

DMH Data Message Handler. An informal name for the TIA IS-124 standard

DMO Direct Mode Operation. Group calling capabilities, e.g. PTT, of a PAMR system. Compare with TMO.

DMT Discrete Multi-Tone line code being proposed for VDSL. Compare with QAM/CAP

DMU Dynamic MIP Key Update. A secure and efficient mechanism for distributing and updating Mobile IP (MIP) cryptographic keys in cdma2000 networks (including High Rate Packet Data which is often referred to as 1xEV-DO). Because the Dynamic Mobile IP Key Update (DMU) procedure occurs at the IP layer directly between the MIP MN and RADIUS or Diameter AAA Server, it may be used to securely bootstrap the MN-AAA key (and other cryptographic keys) in MIP networks using any RAN technology.

DN(1) Directory Number. The number dialed to terminate a call to a phone

DN(2) Domain Name (e.g. cnp-wireless.com).

DNIC Data network identification code

DNIS Dialed Number Identification Service. Identifies the called (not calling) number. Only useful when multiple numbers terminate at the same location (e.g. a regular phone number, 1-800 and 1-900 number). Contrast with CNIP

DNS Internet Domain Name Service/System. See RFC 1035

DOA Dead On Arrival

DoC US Department of Commerce

DOI Domain of Interpretation

DOJ US Department of Justice

Domain A portion of the internet (e.g. cnp-wireless.com)

Donor Switch The switch from which a number has been ported. See LNP

Downlink Path from base station to terminal

DP WIN/CAMEL Detection Point

DPC(1) Destination Point Code for an SS7 message

DPC(2) Downlink Power Control

DPCCH Dedicated Physical Control Channel

DPCH Dedicated Physical Channel

DPDCH Dedicated Physical Data Channel

DPSK Differential PSK

DQPSK Differential Quadrature PSK

DRAC Dynamic Resource Allocation Control

DRM Digital Rights Management

DRNC Drift RNC

DRNS Drift RNS

DS Direct Spread. See CDMA

DS-CDMA Direct Sequence CDMA

DS0 Digital Signal Level 0. A 64 kbps digital link used to carry a single voice conversation or signaling traffic for multiple calls/trunks. In ANSI networks, 8 kbps is usually reserved for in-band signaling (on-hook/off-hook etc.), reducing the bandwidth to 56 kbps

DS1 Digital Signal Level 1. A 1.544 Mbps signaling link carrying 24 DS0 channels

DS1C Digital Signal Level 1C. A 3.152 Mbps signaling link carrying 48 DS0 channels

DS2 Digital Service, Level 2. 6.312 Mbps. Carries 96 DS0 channels (4 DS1 channels)

DS3 Digital Service, Level 3. 44.736 Mbps. Carries 672 DS0 channels (28 DS1 channels)

DSA Digital Signature Algorithm

DSCH Downlink Shared Channel

DSF Dispersion Shifted Fiber

DSI Digital Speech Interpolation

DSL Digital Subscriber Line. See SHDSL, ADSL, SDSL, VDSL

DSLAM DSL Access Multiplexer

DSMA Digital Sense Multiple Access. Access to a shared resource is controlled by sensing a digital signal before attempting an access. Used by CDPD

DSP Digital Signal Processing/Processor

DSR(1) Distributed Speech Recognition

DSR(2) Direct Signal Reporting

DSS-1 Digital Subscriber Signaling System No. 1

DSU(1) Digital Service Unit. Interface between the terminal equipment (DTE) and the service provider's facilities

DTC Digital Traffic Channel

DTCH Dedicated Traffic Channel

DTD Document Type Definition. An XML grammar specification

DTE Data Terminal Equipment

DTM Dual Transfer Mode. Simultaneous voice and data connections with GSM and EDGE, bringing some 3G services to a 2G system (without the wide pipe though!)

DTMF Dual Tone Multifrequency. Tone signaling used by phones

DTN Deflected-To Number

DTX Discontinuous Transmission. A mobile only transmits when the user is talking. This saves battery life, but can introduce some choppiness into conversations

Dual-band A mobile that can support two different frequency ranges. Compare with Dual-mode

Dual-mode A mobile that can support two different technologies. Compare with Dual-band

DUP SS7 Data User Part

DVCC Digital Verification Color Code

DWDM Dense Wave Division Multiplexing

E E-GGSN Enhanced GGSN

E-Mail(1) Electronic Mail

E-OTD Enhanced Observed Time Difference. A positioning technology based on software within wireless phones combined with their existing signal measurement capabilities. Compare with the purely network-based AOA, TOA and TDOA

E-SMR Enhanced SMR. See iDEN

E.164 ITU-T dialing plan standard. Numbers are composed of CC+NSN (NDC + NDC)

E.212 ITU-T mobile identification number standard

E.214 ITU-T standard that allows an E.212 IMSI number to be mapped onto an E.164 number to allow routing through SS7 networks. Unfortunately, this mapping does not work in North America

E1 A digital link carry 32 DS0 channels, with two used for signaling purposes. Used mostly outside North America. Compare with T1

E911 Enhanced 9-1-1 service. Provides the identity and the approximate location of the calling phone

EA(1) Economic Area. A geographical area used by the US FCC to license the AWS A band.

EA(2) Equal Access

EACC Emergency Area Congestion Control

EAP IETF Extensible Authentication Protocol, RFC 4017

EAP-TLS EAP Transport Layer Security. Public key encryption for WiFi.

EAP-TTLS EAP Tunneled Transport Layer Security. Provides mutual authentication of WiFi network and client through the use of network-side certificates.

EAR Export Administration Regulations. Replace ITAR for control of export of encryption technologies

EAS Emergency Alert System. A US government system that transmits audio or text information about emergencies (mostly weather) to radio and TV stations. There has been some talk about extending this to wireless phones via broadcast SMS

Eb Energy of an information bit

EBCDIC Extended Binary Coded Decimal Interchange Code. IBM's byte code for letters, numbers and special characters. Not as good as ASCII because, for example, letters are not all in a single group, making software more awkward

EBGP External BGP. BGP between routers in two different networks.

EBNF Extended BNF. Used to define XML, for example.

EBS Emergency Broadcast System. See EAS

EC Exchange Carrier

ECC Elliptic Curve Cryptography

ECDLP Elliptic Curve Discrete Logarithm Problem. See ECC

ECMA European Computer Manufacturer's Association

ECSA Exchange Carrier's Standards Association. Renamed ATIS several years ago

ECT Explicit Call Transfer

EDAC CDMA Error Detection and Correction coding. See FEC

EDGE Enhanced Data-rates for GSM (or Global) Evolution. Uses 8PSK modulation to increase data rates within the 200 kHz RF bandwidth to a theoretical limit of 384 kbps (474 kbps raw), although per-user rates will be significantly lower because few if any phones can use all 8 available timeslots. A higher speed successor to GPRS. See ADRC

EDI Electronic Data Interchange. Used to transfer business-level data between companies (e.g. invoices, purchase orders). Nowadays, more attention is on XML for this purpose

EDR Efficient Data Representation. Assigns one record to represent a block of 1,000 pooled numbers

EDS Enhanced Dialed Service(s)

EESN Expanded ESN. An idea that never took off. See MEID

EF UIM Elementary File. Compare with DF and MF

EFI External Functionality Interface

EFR Enhanced Full Rate. The standard GSM Voice Coder operating at 12.2 kbps

EGPRS-136 GPRS adapted for use in TIA/EIA-136 networks

EHFC Extended Hyperframe Counter

EIA Electronics Industry Alliance

EIA/TIA-553 Analog AMPS cellular standard. Formerly IS-3

EIR Equipment Identity Register. Stores information about wireless terminals as opposed to subscriptions. Compare with HLR

EIRP Effective Isotropic Radiated Power

ELCA Extended Local Calling Area. Allows toll-free calls to numbers outside the normal toll-free zone, by arrangement with the terminating (usually wireless) carrier

EMA Electronic Messaging Association.

EMC Electro-Magnetic Compatibility

EMF Electro-Magnetic Field or Electro-Motive Force (Voltage)

EMI Exchange Message Interface. A LEC billing record format. Compare with EMR. Contrast with BAF and CIBER

eMLPP Enhanced MLPP. A GSM method for implementing PS

EMR Exchange Message Record. A LEC billing record format. Compare with EMI. Contrast with BAF and CIBER

EMS Enhanced Messaging Service. SMS extended to include simple graphics, audio and enhanced text (e.g. fonts). A precursor to MMS

EMTEL Emergency Telecommunications for ETSI

EN European Norm (Standard).

enum Telephone Number Mapping to an internet address. A method of converting a phone number into a domain name defined by IETF RFC 2916. Take the full number (including country code), reverse it, put a dot between each pair of adjacent digits, append '.e164.arpa' and, there you have it! This format is easier for DNS systems to handle.

EO End Office

EOM End Of Message

EOTD See E-OTD

EP SCP ETSI Project Smart Card Platform

EPE Enhanced Privacy and Encryption. A North American TDMA architecture that secures voice, messages, and data through encryption

Erlang Measure of traffic load. Calculated as rate at which calls arrive divided by the rate at which they are completed

Erlang B A traffic model used to engineer resource groups when blockage is low, and the average holding time is known

Erlang C A traffic model commonly used for provisioning data circuits

ERMES European Radio Messaging System. An ETSI paging system established in the 1990s. All European countries are supposed to provide spectrum for it.

ERP Effective Radiated Power

ERROR RESULT

Message sent to unsuccessfully end TCAP transaction

ES Emergency Service(s), such as 911

ESA Enhanced Subscriber Authentication. A long term replacement to the TIA CAVE algorithm

ESC Emergency Services Call

ESF Extended Superframe Format. DS1 format that is used for most T1 links

ESIF ATIS Emergency Services Interconnect Forum

ESME(1) Emergency Services Message Entity. Entity that receives E911 messages from an MSC (e.g. ALI or S/R)

ESME(2) External SME. Used by SMPP to exchange short messages between incompatible technologies

ESMR Enhanced SMR. Allows ‘cellular’ service as well as traditional SMR services

ESN(1) Electronic Serial Number. 32 bit identifier of an AMPS, CDMA or TDMA mobile. May eventually be replaced by MEID.

ESN(2) Emergency Service Number

ESNE Emergency Services Network Entity. Entity that is connected to an E911 trunk from an MSC (e.g. S/R or PSAP)

ESNX See EESN

ESP(1) Emergency Service Provider

ESP(2) Enhanced Subscriber Privacy. Stronger TIA voice encryption algorithms than those originally provided with CAVE

ESP(3) IETF Encapsulating Security Payload, RFC 2406

ESRD Emergency Service Routing Digits. An NANP number that routes a call to a PSAP and identifies the cellsite or sector that the call originated from

ESRK Emergency Service Routing Key. A temporary phone number that routes an emergency call to the correct PSAP and allows access to information in the ALI

ESZ Emergency Services Zone. A geographical region served by a single emergency call answering service.

ETACS Extended TACS

Ethernet A LAN protocol using collision detection to resolve access contention (CSMA/CD). Available in 10Mbps, 100Mbps and 1Gbps variants. Standardized as IEEE 802.3.

ETR ETSI Technical Report

ETS European Telecommunication Standard

ETSI European Telecommunications Standards Institute

EvDO 1x cdma2000 Evolution for High Speed Data Only. See HRPD and EVDV. A high speed CDMA data system. It does not support voice, except as VoIP. Revision 0 promised 2.4 Mbps download, 153 kbps upload on a 1.25 MHz carrier. Revision A was 3.1 Mbps down, 1.8 up. Revision B was 14.7 Mbps download and 4.9 Mbps upload in a 5 MHz carrier and Revision C promises 100 Mbps download and 50 Mbps upload in a 20 MHz carrier. See LTE and ADRC

EVDV CDMA 1x Evolution - Voice and High Speed Data services. Although it is more flexible, it is so far less popular than EvDO

EVM Error Vector Magnitude. The difference between the received coordinates of a symbol (defined by phase and amplitude) and the intended position (e.g. what was transmitted). This is a measure of error in digital modulation systems such as QAM.

EVRC Enhanced Variable Rate Voice Coder. An IS-95 voice coder for use on CDMA systems

EWC Enhanced Wireless Consortium. An association to promote the development of the IEEE 802.11n WLAN protocol

EWG GSMA Environmental Working Group

F F-BCCH Fast Broadcast Control Channel

F-SCH Forward SCH (from BS)

f1 AKA message authentication function used to compute MAC

f2 AKA Message authentication function used to compute RES and XRES

f3 AKA Key generating function used to compute CK. Compare with f8.

f4 AKA Key generating function used to compute IK. Compare with f9

f5 AKA Key generating function used to compute AK. It may simply generate 0 if concealment of SQN is not required.

f8 AKA Ciphering Function. May be Kasumi. Uses CK, which is derived from RAND using f3

f9 AKA Integrity Protection Function. May be Kasumi. Compare with f4

FA Foreign Agent

FAC(1) FA Challenge

FAC(2) Final Assembly Code. The 2 digit IMEI ME manufacturer identity

FACCH Fast Associated Control Channel

FACH GSM term for FACCH

FAQ Frequently Asked Questions

Fast Fading Fade duration short relative to channel frame length

FBI US Federal Bureau of Investigation

FC Feature Code. An asterisk followed by digits indicating the invocation

of a feature (e.g. *73 may be used to disable call forwarding). Feature codes should be sent to the HLR for interpretation. There is no standardization of feature codes

FCC US Federal Communications Commission

FCCH GSM Frequency Correction Channel; downlink only, correction of MS frequencies, transmission of frequency standard to MS etc.

FCI Forward Call Indicator. Used to indicate whether a number portability query has occurred for this call (to prevent looping)

FCS Frame Check Sequence. A checksum for a transmitted frame

FDCCH Forward DCCH

FDD Frequency Division Duplex

FDDI Fiber Distributed Data Interface

FDM Frequency Division Multiplex. See FDMA

FDMA Frequency Division Multiple Access. Compare with TDMA and CDMA

FDN Fixed Dialing Number

FDTC Forward DTC

FE Functional Entity. A logical element of a network. Not necessarily realized as a physically distinct device

FE-NTS Feature Enhanced NTS

FEC(1) Forward Error Correction

FEC(2) Forwarding Equivalence Class. An identity for packets that all get routed via MPLS in the same way

FER Frame Error Rate. The number of frames in error divided by the total. These frames are usually discarded, in which case this can be called the Frame Erasure Rate

FEXT Far End CrossTalk

FF GSMA Fraud Forum

FFPC CDMA Fast Forward Power Control

ffs For Further Study

FFT Fast Fourier Transform

FHMA Frequency Hopping Multiple Access

FHSS Frequency Hopping Spread Spectrum.

FIB Forward Indicator Bit. Indicates the start of a retransmission cycle in MTP. See BIB

FIFO First in, first out. A queuing methodology similar to lining up for a bank teller. Compare with LIFO

FIPS US Federal Information Processing Standards

FISU Fill-In Signal Unit. The keep-alive message for SS7 MTP

FLEX A Motorola one-way paging protocol that runs at 1600, 3200 or 6400

bps. Compare with POCSAG

FM(1) Frequency Modulation

FM(2) Follow-Me

FOCC Forward Control Channel. Used to send signaling messages from a base station to one or multiple mobiles

Foreign Agent IP node that receives packets from a Home Agent for delivery to a Mobile Node currently in its service area

FPLMTS Future Public Land Mobile Telecommunications Systems. Now IMT-2000

FQDN Fully Qualified DN. A domain name with enough information (including server name, if necessary, to determine a unique IP address). For example, if 'domain.com' had two servers, 'alpha' and 'beta', 'alpha.domain.com' would be fully-qualified, but 'domain.com' would not.

FR Full Rate (e.g. for a voice coder). Compare with HR

FRAD FR Access Device

FSK Frequency Shift Keying

FSN(1) Forward Sequence Number. The sequence number of an MTP frame being transmitted. Contrast with BSN

FSN(2) Frame Sequence Number

FTAM File Transfer, Access and Management

FTI Fractional T1. A customer may lease a portion of a full T1

FTN(1) Forward-To Number

FTN(2) FEC to NHLFE Map

FTP Internet File Transfer Protocol

FTTC Fiber to the curb

FTTH Fiber to the home

FVC Forward analog voice channel, transmitted by an MS

FWA Fixed Wireless Access. See WLL

FWI Flash with Information; used to transmit data from an MS during a call

G G.711 The ITU-T standard for PCM encoding telephone audio on an 64 kbps

channel. Because it operates at an8 kHz sampling rate (8 bits per sample) it can only encode frequencies between 0 and 4 kHz. There are two encoding variants. mu-law and A-law. A-law is used for international circuits and represents smaller signals with greater fidelity.

G3FAX Group III Facsimile service

G95 A sub-group of GGRF investigating roaming between GSM and CDMA systems based on TIA/EIA-95 and cdma2000

GAD Geographic Area Description. GSM 101.109 and 3GPP 23.032 defines this. Related to CGL in ATIS T1.628

GAIT GSM/TIA/EIA-41 Interoperability Trial

GALILEO A European positioning system based on 30 satellites and ground stations. Devices can position themselves based on accurate (atomic clock) time transmitted from the satellites and their knowledge of the satellite's positions. Similar to the US GPS

GAP SS7 ISUP Generic Address Parameter. Used in number portability to carry the LRN

Gateway MSC An MSC designed to receive wireless calls from the PSTN

Gaussian Noise Noise with constant power spectral density across the radio channel.

GBA Generic Bootstrapping Architecture. Uses key material located in an HLR, HSS or AAA to ‘bootstrap’ a key for other purposes, e.g. mobile application security A security association is established by the BSF with both the UE and NAF allowing secure communication between the UE and the NAF, without the NAF having any root key material.

Gbps Giga-bps. A data speed of billions of bits per second. See Mbps and kbps

GCC Group Call Control

GCCS Generic Call Control service for Parlay/OSA

GCF GSM Global Certification Forum

GCR Group Call Register

GDP ISUP Generic Digits Parameter

GECO Global Emergency Call Origination. Allows a phone to make an emergency call in an area where the emergency digits are different than at home.

GEO Geostationary Orbit (for a satellite)

GERAN 3GPP TSG for GSM/EDGE RAN

GETS US Government Emergency Telecommunications Service

GFSK Gaussian FSK

GGRF GSM Global Roaming Forum within the GSM Association. Composed of GAIT, G95 and groups considering interworking with iDEN and TETRA

GGSN Gateway GSN. Connects to other packet data networks (e.g. internet). See SGSN

GHA Global Hexadecimal Address. See MEID.

GHOST GSM Hosted Short Message Teleservice. Allows TIA/EIA-136 messages to be delivered to a GSM MS

GHz One thousand million Hz. A measure of radio frequency

GIF Graphics Interface Format. A common graphics format suitable for computer-drawn graphics with few colors (up to 256). It supports

simple animation. JPEG, PNG or TIFF are more suitable for photographs.

Giga Prefix to indicate one billion (e.g. Giga-bit). Abbreviated G. See Gbps

GII Global Information Infrastructure

GIS Geographic Information System. A system that combines mapping information with domain-specific information that can be queried by computers.

GIWU GSM Inter-Working Unit. An interface to various networks for data communications

Global challenge

Method of authentication using the same random number (RAND) for every mobile in a cellsite or sector

GMLC 3GPP/OMA Gateway MLC

GMM GPRS Mobility Management Protocol

GMSC See MSC-G

GMSK Gaussian MSK

GMT Greenwich Mean Time. The reference point for time zones around the world.

GNSS Global Navigation Satellite System. Used as a generic term for GALILEO. Contrast with GPS

Go Interface between the GGSN and PDF that allows the application of policy (network rules) to bearer usage.

goodput See throughput and badput

GPRS General Packet Radio Service. A GSM-based packet data protocol using up to all 8 of the time slots in a GSM channel. It supports data rates up to 115 kbps, although 10-40 kbps is more likely in practice. Most terminals do not support usage of more than 1-3 timeslots. The difference with HSCSD is that the bandwidth can be shared amongst many users, making it more flexible, but also more susceptible to speed degradation due to overloading. See ADRC

GPS Global Positioning System. A system for determining location based on comparing signals from several US military satellites. Compare with AOA, TOA

GR Telecordia Generic Requirements document

GRE Generic Routing Encapsulation. See RFC 1701

GRI GPRS Roaming Exchange. Provides interconnection, routing, DNS, security and QoS functions

GSL Global Service Logic

GSM Global System for Mobile Communications

GSM-R A GSM-based PAMR system developed by European railways.

GSMA GSM Association

gsmSCF GSM SCF for CAMEL

gsmSRF GSM SRF for CAMEL

GSN GPRS support node. See SGSN, GGSN.

GSTN General Switched Telephone Network. Synonym for PSTN

GT Global Title. A non-native SS7 address based on E.164 DNs, E.212 IMSI, etc.

GTA GT Address

GTAI SS7 SCCP GT Address Indicator

GTP GPRS Tunneling Protocol

GTT(1) Global Title Translation. A method of routing in SS7 networks based on an GTs and not Point Code

GTT(2) Global Text Telephony

GUG GVNS User Group

GUI Graphical User Interface

GUP Generic User Profile

GUTS General UDP Transport Service

GVNS Global Virtual Network Service

GW Gateway

H H.248 ITU-T protocol to control the MGW

H.323 ITU-T recommendation for teleconferencing. See OpenH323

HA MIP Home Agent

HAAA Home AAA

HAC HA Challenge

HANDMREQ TIA/EIA-41 HandoffMeasurementRequest INVOKE message. Being replaced by HANDMREQ2

HANDMREQ2 TIA/EIA-41 HandoffMeasurementRequest2 INVOKE message. Used by the Serving MSC to determine the signal strength being received by a neighboring Candidate MSC. Replaces HANDMREQ2

Handoff The process of a MS changing from one frequency in one cell or sector to a different frequency in a neighboring cell or sector

HARQ Hybrid ARQ

HC Home Country

HCM Handset Configuration Management. See IOTA

HDB3 High Density Bipoloar Order 3 Encoding

HDLC High Level Data Link Control

HDML Handheld Markup Language

HDR High Data Rate. High speed data-only version of CDMA, standardized as EvDO. Now called HRPD

HDSL High bit rate DSL. Symmetric DSL used for corporate networking

HE Home Environment

Hertz A unit of frequency. See MHz, GHz, kHz

HF Hyperframe

HFC(1) HF Counter

HFC(2) Hybrid Fiber-Coax

HG Header Generator

HI Handover Interface

HINFO Host Information

HIPPI High-Performance Parallel Interface

HLPI Higher Layer Protocol Identifier

HLR Home Location Register

HMAC Hashed MAC

HNI Home Network Identifier. The MCC and MNC prefix of a group of IMSI codes.

Home Address An IP address permanently assigned to a device that is supported by Mobile IP. Messages routed to this address will arrive at the HA.

Home Agent IP node that receives packets at a Mobile Nodes static address and forwards them to a Foreign Agent for delivery at its current (‘care-of’) address

Home MSC The MSC to which the PSTN routes based on an MDN

HomeRF Promoters of the SWAP protocol for in-home wireless networking. This protocol was abandoned in 2003.

HPC High Probability of Completion

HPLMN Home PLMN

HPS Home PS

HR Half Rate (e.g. for a voice coder). Compare with FR

HRFWG HomeRF WG. Note that this protocol was abandoned in 2003

HRL Header Reduction Lower

HRPD cdma2000 High Rate Packet Data (formerly EvDO and HDR). It combines TDM on the forward link to provide from 38kbps to 2.5Mbps data rates. The reverse link supports speeds from 9.6kbps to 154kbps

HRU Header Reduction Upper

HS-DSCH HSDPA DSCH. A high speed channel for transmitting data to a W-CDMA mobile.

HS-PDSCCH HSDPA DL control channel

HS-PDSCH HSDPA DL physical channel

HSCSD High Speed Circuit Switched Data. GSM enhanced to allow the concurrent use of up to four timeslots, providing a theoretical maximum 57.6 kbps data rates, although maximum rates of 28.8kbps

to 43.2kbps are more realistic in practice. The main difference with GPRS is that the timeslots are assigned exclusively to one mobile for the duration of a data call.

HSDPA 3GPP High Speed Downlink Packet Access. Provides higher data rates ‘down’ from the network to the mobile at about 1.5 Mbps in a 5 MHz carrier. Uplink speeds will be the same as EDGE – 384 kbps. See HSUPA and HSPA Evolution. See ADRC

HSG Header Stripping and Generation

HSPA Evolution

An evolution of HSDPA and HSUPA that is promising downlink speeds of 28 Mbps, uplink speeds of 11.5 Mbps in a 5 MHz carrier. See ADRC

HSS 3GPP Home Subscriber Server. Similar to AAA

HSSI High Speed Serial Interface. A serial interface that can be used for very short distances (up to 50 feet), supporting speeds up to 52 Mbps

HSUPA 3GPP High Speed Uplink Packet Access. Complements HSDPA by providing higher throughput on the W-CDMA link for uploading (MS to network). Rates for initial systems will be about 1 Mbps but eventually 5.76 Mbps is promised. The RTT is estimated as under 50 ms. See HSPA Evolution and ADRC

HTML Hypertext Markup Language

HTTP Hypertext Transfer Protocol . See RFC 2068

https Secure HTTP

Hyperband Handoff

Handoff between two different frequency bands (e.g. 800 MHz cellular and 1800 MHz PCS)

Hz Cycles per second. A measure of radio frequency

I I-CSCF Interrogating CSCF. Main contact point for IMS connections to a

carrier's subscribers

I-SCM Interrogating SCM

I-WLAN WLAN Interworking with a 3GPP cellular network.

IA5 International Alphabet 5. Basically the ASCII character set

IAM SS7 ISUP Initial Address Message. Used to initiate a call

IANA Internet Assigned Number Authority. Mostly superseded by ICANN

IAP Intercept Access Point. A point within the telecommunications network that provides voice or data for CALEA interception to a DF

IAPP Inter-Access Point Protocol. An IEEE protocol to allow the secure transfer of MS context from one AP to another. It is based on IEEE 802.11f.

IBC Iterated Block Ciphers

IC(1) see IXC

IC(2) Integrated Circuit

ICANN The Internet Corporation for Assignment Names and Numbers. Performs top level resource assignment tasks for the internet, e.g. for domain names and IP addresses.

ICCID GSM identifier for a SIM or UIM (‘smart card’). 10 bytes long (or 20 for some older cards) allowing up to 19 BCD digits to be included. Assigned according to ITU-T Recommendation E.118

ICMP Internet Control Message Protocol. Method for reporting errors and performing loopback testing on the internet

ICO Intermediate Circular Orbit

ICS Implementation Conformance Statement

IDB ITS Data Bus (SAE J2366)

iDEN Integrated Digital Enhanced Network. Motorola’s proprietary system for E-SMR, used by Nextel and others. Based on GSM

IDL Interface Description Language

IDSL ISDN Digital Subscriber Line. Just a fancy name for ISDN

IE Information Element

IEC(1) See IXC

IEC(2) Internet Engineering Consortium

IEC(3) International ElectrotechnIcal Commission and the identity of standards produced by this organization.

IEEE Institute of Electrical and Electronic Engineers

IEEE 802.15.1 The IEEE Standard for Bluetooth

IEEE 802.15.4 The IEEEStandard for ZigBee

IEEE-ISTO IEEE Industry Standards and Technology Organization

IESG Internet Engineering Steering Group. Group that oversees the activities of IETF

IETF Internet Engineering Task Force. Standards setting body for the Internet

IF Information Flow

IFAST International Forum on AMPS Standards Technology. Allocates IRM and SID codes

IFFT Inverse FFT

IGP Interior Gateway Protocol. See MPLS

IIF Interworking and Interoperability Function

IK Integrity Key. Protects (via encryption) the contents of signaling messages. In AKA it is derived from RAND using f4. It is applied to messages using f9

IKE Internet Key Exchange Protocol

ILEC Incumbent LEC. The former monopoly local telephone carrier. cf

CLEC

ILM Incoming Label Map. See MPLS

IM(1) IP Multimedia. A network using IP to transport voice, signaling, text, video etc.

IM(2) Instant Messaging

IM-MGW IM Media Gateway Function

IMAP4 Internet Message Access Protocol. IETF RFC 2060

IMC Internet Mail Consortium

IMD Inter-Modulation Distortion. The interaction of two or more signals, producing an unwanted additional signal

IMEI 56 bit GSM International Mobile Equipment Identity. Composed of TAC + FAC + SNR + spare digit. A check digit is also included, but not always transmitted. See also IMEISV and MEID

IMEISV IMEI with Software Version Number. Composed of TAC + FAC + SNR + SVN

IMGI Inernational Mobile Group Identity

IMM See IM

iMode Japanese (NTT DoCoMo) wireless internet access system. See cHTML

IMRN IP Multimedia Routing Number

IMS IP Multimedia Subsystem. An All-IP wireless system, where data, voice and signaling are all carried as IP packets.

IMSI International Mobile Subscriber Identity. Formerly called International Mobile Station Identity. Based on the ITU-T E.212 numbering plan. Composed of MCC MNC and MSIN. The only subscription identifier used by GSM and the future subscription identifier for CDMA.

IMSI_M cdma2000 MIN-based IMSI.

IMSI_O Operational value of IMSI used by a cdma2000 MS. Either IMSI_M or IMSI_T

IMSI_O_S The last 10 digits of IMSI_O. Used for compatibility with older CDMA systems that relied on the 10 digit MIN.

IMSI_T True IMSI used by cdma2000. Compare with IMSI_M. See IMSI_O

IMT-2000 International Mobile Telecommunications for the year 2000 (or thereabouts)

IMTS-2000 The ITU 3G initiative. It does not define specific protocols, but just the performance goals for them, such as bandwidth. Specifications are being developed by 3GPP and 3GPP2.

IMUI International Mobile User Identity

IN Intelligent Network. Wireless equivalents are WIN and CAMEL

INAP IN AP. The IN messaging protocol

INC Industry Numbering Committee (for the NANP)

INI IRM Network Identifier. The first four digits that uniquely identifies a carrier HLR

INM Integrated Network Management

INN Internal Network Number

Integrity Preventing information (e.g. a data transmission) from being manipulated. This can be accomplished by putting a MAC on each message.

Interface A connection between two network elements. Compare with Protocol

Interleaving Mixing of bits upon transmission according to a simple pattern (e.g. organizing bits in a matrix by columns and transmitting by rows) to somewhat randomize the output and protect from burst of noise on the RF channel

Intermodulation Interference

RF interference within a channel generated as one or more intermodulation products within the receiver itself, typically as the result of the presence of very strong signals in adjacent bands. Contrast with Systemic Interference and Non-systemic Interference

Intserv Integrated Services

INVOKE Message sent to initiate an TCAP transaction

IOS Inter-Operability Standard. A version of the TIA/EIA-634 A-interface that enhances inter-vendor compatibility

IOT Inter-Operator Tariff

IOTA IP-based Over-the-Air configuration management

IP(1) Intelligent Peripheral

IP(2) Internet Protocol

IP-M IP Multicast

IPCP PPP IP Control Protocol

IPDR Internet Protocol Detail Record. An internet oriented record for carrying charging details for services. Compare with CIBER, BAF, TAP, EMI

IPHC IP Header Compression. Provides compression (and decompression) of TCP, UDP and IP headers.

IPLMN Interrogating PLMN

IPoA IP over ATM

IPR Intellectual Property Rights (e.g. patents). See DRM.

IPSEC IP Security. Compare with SSL (for TCP). See IETF RFC 2401. Also spelled IPSec

IPv4 IP Protocol Version 4. The version currently in use in the internet, using 32 bit addressing. See also IPv6.

IPv6 IP Protocol Version 6. The version that is supposed to provide significantly larger and more powerful addressing, and eventually replace IPv4. Don’t hold your breath

IPv6CP IPv6 Control Protocol

IR(1) Intelligent Roaming

IR(2) Infra-Red

IR(3) Initialization and Refresh Packet. RFC 3095

IRA International Reference Alphabet

IRDB IR Database. A database that can be loaded into a phone over the radio interface that prioritizes systems that may be detected by a phone based on carrier agreements

IREG GSMA International Roaming Experts Group.

IRG IFAST International Roaming Guide

IRI Intercept (i.e. LAES) Related Information

IRM International Roaming MIN. A mobile subscription identifier beginning with the digit 0 or 1 to avoid conflict with NANP MINs

IRP Integration Reference Point

IRS Internet Reachability Service

IS TIA Interim Standard

IS-124 Wireless call detail and billing record format for online transfer

IS-136 Second generation TDMA air interface standard

IS-2000 cdma2000 air interface standard. A successor to TIA/EIA-95-B

IS-41 Wireless intersystems operation standard. Now called TIA/EIA-41

IS-41-C IS-41 Revision C (Intersystem Operations Standard)

IS-54 First generation TDMA Radio Interface standard

IS-634 See TIA/EIA-634

IS-637 CDMA short message service standard

IS-683 see TIA/EIA-683

IS-756 A TIA standard for WNP

IS-801 TIA/EIA interim standard for CDMA MS-assisted position determination

IS-91 Most advanced analog air interface standard (including NAMPS)

IS-93 Wireless-PSTN interface standard

IS-95 cdmaOne CDMA air interface standard

ISAKMP Internet Security Association and Key Management Protocol

ISC International Switching Centre

ISDN Integrated Services Digital Network. PSTN utilizing SS7 interfaces

ISDN-UP See ISUP

ISI Inter-Symbol Interference

ISIM IMS SIM

ISIS Intermediate System - Intermediate System IP routing algorithm.

ISM Industrial, Scientific, Medical frequency band (2.45-2.5 GHz).

Available around the world for unlicensed applications, generally using low power and short distances

ISMA Interference Sense Multiple Access

ISO International Organization for Standardization

ISO-8859-1 The most common 8-bit character set used for web pages. An ISO/IECstandard. Also see UNICODE

isotropic Radiating equally in all three dimensions (as opposed to directional, with energy being focussed more in some directions than other).

ISP Internet Service Provider

ISUP ISDN User Part. SS7 signaling between switches. Standardized in ANSI T1.113 and ITU-T Q.760-769

ITAR US International Traffic in Arms Regulations. These rules used to govern export of encryption technology in the US and, to some extent, in Canada. Replaced by EAR

ITN Individual Telephone Number Pooling. Phone numbers can be assigned to carriers one at a time, instead of in blocks of 1,000 or 10,000

ITS(1) Intelligent Transportation System (“Smart Highways”)

ITS(2) IP Transport Subsystem

ITU International Telecommunications Union

ITU-R ITU - Radio Communications Division

ITU-T ITU - Telecommunications Division

Iu Interface between an RNC and CN (MSC, SGSN or CBC). Support for this within GSM has been suggested, but is unlikely. See also Iub, Iur.

IUA ISDN Q.921 User Adaptation Layer

Iub A 3GPP interface between an RNC and a Node B. See Iu, Iur.

Iur A 3GPP interface between two RNCs. This is a logical interface, and the RNCs may not be connected by point-to-point physical links. See Iu, Iub.

IV Initialization Vector. A 24-bit session-specific key for WEP

IVR Interactive Voice Response

IVRU IVR Unit

IWF Inter-working Function. Used for wireless data interworking between digital mode data and analog (e.g. modems)

IXC Inter-eXchange Carrier. A carrier licensed to provide long distance services

J J-STD- Joint ATIS-T1/TIA standard

J-STD-025 LAES standard jointly produced by ATIS T1 and TIA TR-45

J-STD-034 Wireless E911 Phase I standard (cellsite and mobile identification,

callback capabilities). See J-STD-036

J-STD-036 Wireless E911 Phase II standard (position of caller within 125m/400ft). See J-STD-034

J2EE Java 2 Enterprise Edition

J2ME Java 2 Micro Edition

JAIN Java APIs for Intelligent Networks

Java A C-like programming language that is compiled into a virtual machine language providing efficiency close to that of languages compiled into native machine code while providing portability of the compiled program. Each computer system that wants to run Java has to provide a virtual machine

JCP Java Community Process

JDC Japanese Digital Cellular

JFIF JPEG File Interchange Format

JIP ISUP Jurisdiction Information Parameter

JPEG Joint Photographic Experts Group. Not usually used to refer to the group, but a graphics format created for them that is suitable for digital photographs and similar images. It supports 24 bit color as well as variable levels of compression and quality. It should be referred to as JFIF, but isn't. cf GIF, PNG, TIFF

JSR Java Specification Request

JSR 177 JSR for Security and Trust services API for J2ME

JTACS Japanese TACS

JTC Joint Technical Committee (e.g. with members of more than one SDO)

K Kasumi A block cipher used by AKA for the A5/3, f8 and f9 algorithms. See

the wikipedia entry for more details

kbps kilo-bps. A data speed of billions of bits per second. See Mbps and Gbps

Kc GSM cipher key. Used for voice encryption

KDF Key Derivation Function

KG Key Generator

kHz kilo-Hertz. Thousands of cycles per second. See MHz and GHz

Ki GSM subscriber authentication key

kilo Prefix to indicate one thousand (e.g. kilo-bit). Abbreviated k. See kbps

KSG Keystream Generators

KSI Key Set Identifier

KSS Key Stream Segment

L

L1 Layer 2

L2 Layer 2

L2TP Layer 2 Tunnel Protocol. Defined in RFC 2661. Successor to PPTP. IP packets are wrapped in a layer containing another set of IP addresses and possibly also control messages. The detailed format varies depending on whether the transport protocol is IP, UDP or another PSN type.

L3 Layer 3

LAC(1) Link Access Control

LAC(2) Location Area Code. 16 bit number identifiying a location area (i.e. group of base stations) within a GSM PLMN

LAES Lawfully Authorized Electronic Surveillance. See CALEA, J-STD-025, surveillance

LAI GSM Location Area Identity. Composed of MCC + MNC + LAC

LAK Local Authentication Key

LAN Local Area Network. Compare with WAN, MAN.

LAP Link Access Protocol

LAPB Link Access Protocol, Balanced

LAPD Link Access Protocol for the ISDN D Channel

LATA Local Access and Transport Area. US local telephone service area

LB Letter Ballot

LBA Location Based Application

LBC Last Batch Count. Exchanged by CIBER billing clearinghouses to ensure they do not get out of sequence with each other.

LBS Location Based Services

LCP Link Control Protocol. A subset of PPP that is used to negotiate and establish link capabilities, including authentication

LCS Location Services. This usually implies positioning of an MS for commercial services, not emergency services

LCSM LCS Manager

LDAP Lightweight Directory Access Protocol. See IETF RFC 3377. Compare with X.500 DAP

LDP Label Distribution Protocol. See MPLS

LDT Location Determination Technology

LEA Law Enforcement Agency

Leakage Inability to bill for a service

LEAP Lighweight EAP. A Cisco proprietary version.

LEC Local Exchange Carrier (wireline carrier for local calls). Also see ILEC and CLEC

LEMF Law Enforcement Monitoring Facility (for LAES)

LEO Low Earth Orbit

LER Label Edge Router. See MPLS

LERG Local Exchange Routing Guide. Includes a list of valid number blocks in the NANP

LFB Lookahead For Busy

LIDB Line Information DataBase. Used for validating collect calls, 3rd party calls, etc.

LIF Location Interoperability Forum within OMA

LIFO Last in, first out. A queuing methodology similar to stacking dishes and using the dish on the top of the stack. Compare with FIFO

LIR Location Identification Restriction. Prevents the location of a mobile phone from being revealed (with legal exceptions for E911, etc.)

LLA-RHOC Link Layer Assisted ROHC

LMDS Local Multipoint Distribution Service. Uses the 27.5-31.3 GHz frequency band to serve mulitple points within a radius of 3-5km. Most carriers in this space have abandoned it or gone bankrupt. See MMDS.

LMM Localized Mobility Management to improve local handover performance in Mobile IP

LMR Land Mobile Radio

LMSD Legacy MS Domain. Refers to existing SS7-based telecommunications systems, when accessed from an All-IP system. See MMD

LMSI Local Mobile Station Identity. See TMSI

LMU GSM Location Measurement Unit

LND Last Number Dialed

LNP Local Number Portability. Allows consumers to keep a phone number (MDN) when changing carriers within the same geographical region

LNPWG Local Number Portability Working Group of NANC

LOS Line of Sight. A direct path through the air from transmitter to receiver. Always desirable for wireless communications, although not always necessary (e.g. for cellular/PCS)

LPC Linear Predictive Coding

LPDE Local PDE

LPDU Link Protocol Data Unit. A frame

LRF Location Registration Function. See WIN

LRN Location Routing Number. A routing number that identifies the terminating switch for a Ported DN

LSB Least Significant Bit or Byte. Compare with MSB

LSMS Local Service Management System. Telephone carrier interface that downloads information from the NPAC into one or more NPDBs

LSP Label Switched Path. See MPLS

LSPI Proposed SS7 ISUP Local Service Provider Identification

LSR Label Switching Router. See MPLS

LSSU Link Status Signal Unit. The link status message for SS7 MTP

LT Line Termination

LTE A GSM competitor to EvDO Revision C promising similar data rates. See ADRC

LUDT Long UDT. Supports messages up to 3 kilobytes in length

M M2M Machine To Machine. Communications between unattended machines.

Most electronic communications is between machines but in many cases, such as a cellphone or PC, this is usually only because a person is using the device. An example of an M2M scenario is when a heat or alarm sensor communicates with a central computer, perhaps with the central computer providing feedback to other devices to shut off a malfunctioning machine, turn on fans or other automated control

M2PA SS7 MTP2 Peer-to-Peer User Adaptation Layer

M2UA SS7 MTP2 User Adaptation Layer

M3UA SS7 MTP3 User Adaptation Layer. Resides above SCTP and below SCCP in an IP telecom signaling protocol stack.

MAAL Management ATM Adaptation Layer. Maps management requests from system management to SAAL. See ATIS T1.652

MABEL Major Account Billing Exchange Logistical Record. Defined by Cibernet to facilitate centralized billing for large account customers

MAC(1) Medium Access Control

MAC(2) Message Authentication Code. In AKA, a value derived from SQN, RAND and AMF using f1 that shows that the sender was in possession of certain secret information (i.e. is authentic).

MACA Mobile Assisted Channel Allocation. Mobile determines the best alternate cellsite to originate a call in, when no channels are available in the current site

MAH Mobile Access Hunting. Termination to one of a group of mobiles

MAHO Mobile Assisted Handoff. Mobile measures signal strength at neighoring base stations to determine which to handoff to

MAN Metropolitan Area Network. Compare with LAN, WAN

MANET Mobile ad hoc Network. A collection of wireless nodes that can dynamically form a network without any fixed network infrastructure.

MAP Mobile AP. Protocol that interconnects wireless telephone systems. See GSM and TIA/EIA-41

MBI MIN Block Identifier. The first 6 digits (usually) of a North American MIN, when assigned separately from the MDN. The first digit is always 2-9 (inclusive). Digits 0 and 1 are reserved for IRM codes.

MBMS UTRA Multimedia Broadcast and Multimedia Service

Mbps Mega-bps. A data speed of millions of bits per second. See Gbps and kbps

MC(1) Short Message Center

MC(2) Multi-carrier

MCC E.212 Mobile Country Code. First 3 digits of IMSI

MCFTP Multi-Channel Flow Treatment Protocol

MCI Malicious Call Identification

MCID See MCI

MCL Minimum Coupling Loss. The minimum loss required between a transmitter and a nearby receiver to avoid adversely affecting receiver performance.

Mcps Million Chips-per-second. See CDMA and W-CDMA

MCSE Microsoft Certified Systems Engineer

MD-IS Mobile Data - Intermediate System. A CDPD term

MD5 Message Digest 5. A secure hashing algorithm. See SHA-1

MDN Mobile DN

MDS Multi-Point Distribution System.

ME Mobile Equipment. Synonym for UE. Contrast with MS

MEA Message Encryption Algorithm

Mega Prefix to indicate one million (e.g. Mega-bit). Abbreviated M. See Mbps

MEGACO Media Gateway Control - IETF Working Group

MEI Mobility Event Indicator

MEID A 56 bit Mobile Equipment Identity for CDMA and TDMA MS. Similar to the GSM IMEI, but allowing hexadecimal digits, and with a simplified structure (2 digit region code, 6 digit manufacturer code, 6 digit serial number). Compare with IMEI, ESN. ESN and MEID are assigned by the TIA.

MEMS Micro-Eletronic Mechanical System

MESA Mobility for Emergency Service Applications. A joint ETSI/TIA project to increase the interoperability of emergency service communications.

mesh A form of networking where access to a server can be accomplished by routing through other clients that are physically closer

meta-language A language that can be used to define other languages. See ASN.1 and BNF

MExE 3GPP TSG-T Mobile Execution Environment

MF(1) Multi-frequency tone signaling. Used for trunk signaling

MF(2) UIM Master File. Compare with EF and DF

MG Media Gateway

MGC MG Controller

MGCF MG Control Function

MGCP MG Control Protocol. A VoIP call control standard. Also see older protocol SGCP

MGW Media Gateway. Interface between packet environment of the CN and circuit environment of PSTN

MHz Million Hz. A measure of radio frequency

MIB Management Information (Data)Bases

MIH Media Independent Handover. An IEEE 802.11 term indicating handover between 802.11, 802.3 or 802.16 and another radio interface.

MIHF MIH Function. A cross-layer entity, defined by IEEE 802.21, that provides mobility support through SAPs offering Event, Information and Command services.

MIME Multipurpose Internet Mail Extensions

MIMO Multiple Input, Multiple Output antennas. This increases throughput and reduces bit error rates compared to traditional antenna systems which transmit and receive through a single antenna.

MIN Mobile Identification Number. 10 digit identifier of a mobile subscription. IRM for cdma2000, TDMA, AMPS. A MIN intended for use outside North America is usually an IRM assigned by IFAST

MIN1 The last 7 digits of a MIN encoded in a wierd, but compact, 24 bit binary format

MIN2 The first 3 digits of a MIN encoded in a very wierd, but compact, 10 bit binary format

minimization Removal of information that has been collected, but that is outside the scope of a court order. See LAES

MIP Mobile IP. IETF RFC 2002

MIPS Million Instructions per Second. Measurement of processor speed

MISP Mobile Internet Service Provider

MLC OMA/3GPP Mobile Location Center

MLP Mobile Location Protocol. An XML-based protocol developed by the OMA LIF group.

MLPP Multi-Level Precedence and Pre-emption

MLTS Multi-line Telephone System

MM(1) Mobility Management

MM(2) Multimedia Message

MM1 MMS interface between UA and MMS Relay/Server

MM2 MMS interface between MMS Relay and MMS Server

MM3 MMS interface between MMS Relay/Server and External Servers for fax, email etc.

MM4 MMS interface between two MMS Relay/Servers

MM5 MMS interface between MMS Relay/Server and HLR

MM6 MMS interface between MMS Relay/Server and user databases

MM7 MMS interface between MMS Relay/Server and VAS applications

MM8 MMS interface between MMS Relay/Server and billing systems

MMD Multi-Media Domain. An IP-based signaling system supporting voice, video, graphics, sound and application data, such as email in an integrated fashion. Contrast with LMSD. See IMS

MMDS Multi-channel Multi-Point Distribution Service. Uses the 2.1-2.7 GHz frequency band. The success of this technology has been about as poor as its cousin, LMDS.

MMI Man-Machine Interface

MML Man-Machine Language. A human-readable language devised for communications between a human and a computer. Examples of formal languages in telecommunications are ITU-T Z.300 and the related TL1. These languages are textual and most humans are unlikely to want to use them directly, so they are more likely to take the place of a human-readable (i.e. ASCII character) protocol, with a GUI for the human to view and control the interactions with the computer more effectively and pleasantly.

MMS MM Service (e.g. text, audio, graphics)

MMSE Multimedia Messaging Service Environment

MMSNA MMS Network Architecture

MMTA MultiMedia Telecommunications Association. A subsidiary of TIA

MN Mobile Node. An internet term for a mobile device capable of IP communications. See Mobile IP

MN-FA MN Foreign Authentication. An extension to MIP that provides stronger authentication. See IETF RFC 3012

MNC E.212 Mobile Network Code (identifies an individual carrier, or a portion of a carrier network). Part of IMSI

MNIC Mobile Network Identification Code

MNID MN Identification

MNO Mobile Network Operator. A carrier.

MNP Mobile Number Portability. See LNP, WNP

MO Mobile Originated/Originating

Mobile IP A set of protocols that allows a MN to roam on the internet. Not widely implemented.

Mobile Node An IP network node that has both a static address and a ‘care-of’ address associated with it. IP packets can be routed to it via a Home Agent (at its static address) and a Foreign Agent (at its care-of address)

Mobility The capability of a device to initiate or receive services in many

different systems, and to maintain session while travelling between systems.

Mobitex An Ericsson Wireless Data protocol, once known as RAM Mobile Data in the US.

MOS Mean Opinion Score. A method of measuring quality (e.g. of wireless voice transmission) by asking people to rank their opinion on a numeric scale, and then averaging the results. Sophisticated, huh!

MoU(1) GSM Memorandum of Understanding. The guidelines under which GSM systems are implemented

MoU(2) Minutes of Use. A common measure of the usage of a group of subscribers

MPC Mobile Positioning Center. Interfaces between MSC, PDE, CRDB and ESME

MPCAP Mobility Positioning Capabilities

MPCI Mobile PCI

MPEG Motion Pictures Experts Group. Not usually used to refer to a group but a format for audio/video compression (and, obviously, decompression)

MPLS Multi Protocol Label Switching. An IP protocol (RFC 3031) designed to provide preferred treatment to priority traffic to achieve a higher QoS. Every packet labeled with the same FEC gets the same treatment

MPS Minimum Performance Standards/Specification.

MRF Media Resource Function. Provides conference bridges, announcements, tones and so forth to IP-based telephony networks. See MRFC and MRFP

MRFC MRF Controller

MRFP MRF Processor. Provides tones, recordings, conference bridges etc.

MRP Market Representation Partner. A participant in the 3GPP or 3GPP2 process that represents the marketing of technology in a region, such as 3G Americas for 3GPP or CDG for 3GPP2.

MS(1) Mobile Station (wireless phone)

ms(2) Milliseconds. Thousandths of a second. Also msec

MS-SME SME embedded in MS

MSA Metropolitan Statistical Area. CGSA for urban cellular systems. Also used for licensing the FCC AWS D band.

MSAG Master Street Address Guide. A database of street names and house number ranges that define ESZ and their associated ESNs to enable proper routing of 911 calls. See E911.

MSB Most Significant Bit or Byte. Compare with LSB

MSC Mobile Switching Centre

MSC-G See Gateway MSC

MSC-H See Home MSC

MSC-O See Originating MSC

MSC-S Serving MSC

MSC-V Visited MSC. The MSC which a mobile is currently registered in

MSCIN MSC Identification Number

msec Milliseconds. See ms

MSEIA MS Emergency Information Assistance

MSID Mobile Station Identifier. A MIN or an IMSI. See IMSI_O

MSIN Mobile Subscriber Identity Number. Unique number assigned to a subscriber as part of IMSI

MSISDN MS ISDN number. Same as MDN

MSK Minimum Shift Keying. FSK where peak-to-peak FM deviation is half the data rate

MSO CDMA Markov Service Option

MSP Multiple Subscriber Profile

MSRN Mobile Station Roaming Number. The GSM equivalent of the ANSI-41 TLDN

MSS(1) Mobile Satellite System/Service

MSS(3) Multimedia Streaming Service

MSU Message Signal Unit. The payload message for SS7 MTP

MT Mobile Terminated/Termination/Terminal. The UE is composed of the MT and SIM/USIM and possibly other peripherals

MTA(1) Major Trading Area

MTA(2) Mail Transfer Agent

MTE Months to Exhaust. The time at which a numbering resource (e.g. area code) is expected to be fully utilized

MTP Message Transfer Part (SS7 transport layer)

MTP2 MTP Layer 2

MTP3 MTP Layer 3

MTSO Older term for MSC

MTTR Mean Time to Restore (after failure)

MTU Message Transfer Unit

Multipath A radio link between the transmitter and receiver comprised of multiple paths which include intermediate reflections from various surfaces, usually due to non-line of sight communication paths

MUX Multiplexer

MVNE Mobile Virtual Network Enabler. Provides infrastructure and services such as billing, subscriber management and operations support to MVNOs.

MVNO Mobile Virtual Network Operator. A company that markets cellular

service but contracts with facilities-based cellular carriers to actually provide the coverage

mW milli-Watt

MWIF Mobile WIreless Internet Forum. Promotes the use of a single All-IP network for future wireless systems (e.g. convergence of 3GPP and 3GPP2 protocols)

MWN Message Waiting Notification (e.g. stutter dial tone or an indication on a wireless phone's display)

MWNE Managed Wireless Network Entity. A piece of equipment that provides OA&M data

MX Mail Exchange (internet mail server)

N N-1 Switch The switch responsible for LNP queries

N-AMPS See NAMPS

NAA Network Access Application

NACK Negative ACK

NAF Network Application Function of GBA.

NAI Network Access Identifier. This is an email-like address format used to identify a AAA or a device with an interface to one.

NAM Number Assignment Module. A portion of a mobile phone that stores a single user profile, including MIN and IMSI, but not ESN

NAMPS Narrowband AMPS

NANC North American Numbering Council. The organization responsible for overseeing the distribution of telephone numbers in the NANP

NANP North American Numbering Plan

NANPA North American Numbering Plan Administrator (or Area)

NAPTR Number Authority Pointer. See IETF RFC 2915.

NAS(1) Network Access Servers

NAS(2) Non-Access Stratum. Protocols between the UE and the core network that are transparent to the RAN (e.g. SMS)

NAT Network Address Translation. Maps an internal set of IP addresses to an external set (perhaps assigned dynamically by DHCP)

NBAP Node B Application Part

NCAS Non-Call Associated Signaling. Compare with CAS

NCG Network Capability Gateway. Obsolete. See OSA-SCS

NCGW Synonym for NCG. Obsolete. See OSA-SCS

NCS National Communication System. Responsible for US Government communications, including WPS and GETS

NDC E.164 National Destination Code

NDS Network Domain Security

NE Network Entity

NEBS Network Equipment Building Systems

Net Additions Increase in new revenue-generating subscribers over a time period (usually a quarter year)

NFCC Network Firewall Configuration and Control

NFS Number Field Sieve. Used in cryptography

NGN Next Generation Network. ITU-T term for future wireless systems with even higher speed data capabilities.

NHLFE Next Hop Label Forwarding Entry. See MPLS

NHP No-Header Packet. See RFC 3242

NI(1) Network Identity

NI(2) Number Incomplete

nibble Four bit

NID Network Identification. A number that uniquely identifies a portion of a wireless carrier’s total system. Used by TIA/EIA-95 (CDMA) systems

NIDS Network-Initiated Data Session

NIIF Network Interconnection Interoperability Forum

NIST US National Insitute of Standards and Technology

NL Neighbour List

NMR Network Measurement Results

NMSI National Mobile Subscription Identity. MNC + MSIN

NMT Nordic Mobile Telephone. An analog cellular system available either in the 450 MHz or 900 MHz bands

Node B Logical node in the 3GPP RNS responsible for radio transmission/reception in one or more cells to and from the UE. Terminates the Iub interface towards the RNC.

Non-repudiation

Ensuring that a communication cannot be disavowed later

Non-systemic Interference

RF interference within a channel used in a wireless system that emanates from a transmitter that is not part of the same system, and that may have undefined channel characteristics. This is of greatest concern for systems operating in unlicensed bands, such as ISM.  Compare with Systemic Interference

nonce A number that is used only once. Often used in cryptography

NP Number Portability

NPA NANP Numbering Plan Area (i.e. area code)

NPAC NP Administration Center. Often used to refer to the NPAC SMS

NPDB Number Portability Database. A list of ported numbers and associated

LRNs used for LNP routing

NPDE Network PDE

NPDU Network Protocol Data Unit. A packet

NPI Numbering Plan Identifier

NPM Non-Public Mode Service

NPRM FCC Notice of Proposed Rulemaking

NRM Network Reference Model (e.g. TIA/EIA/TSB-100)

NRN Network Routing Number

NRTL Nationally Recognized Test Lab

NRZ Non-RZ

NS Authoritative Name Server for a Domain. Converts between a domain name (e.g. cnp-wireless.com) and an IP address and related information

NS/EP US National Security and Emergency Preparedness. See WPS

NSA US National Security Agency. Keeps a tight grip on exports of US encryption technology

NSDPB&S Non-signaling Data Protocol for Billing and Settlement. subset of IS-124

NSDPF Non-signaling Data Protocol for Fraud. A subset of IS-124

NSDU Network Service Data Unit

NSEP National Security and Emergency Preparedness. People who are eligible for PAS/PACA

NSN National Significant Number. All of an E.164 number apart from the CC, i.e. NDC + SN

NSS Network and Switching Subsystem

NSTAC US National Security Telecommunications Advisory Council

NT Network Termination

NTIA U.S. Dept. of Commerce National Telecommunications and Information Administration

NTS Number Translation Service

Number Pooling

Sharing a block of numbers between carriers. In the NANP this means that a block of 10,000 numbers is shared (currently in multiples of 1,000) by several carriers. Pooling is implemented using LNP

Number Porting

See LNP or WNP

NVSE Normal Vendor Specific Extension

NXX Digits 4-6 of a NANP directory number. N can be any digit 2-8, while X can be any digit 0-9

O

O-BCSM Originating BCSM

O/E Odd/Even

O&M Operations and Maintenance

OA&M Operations, Administration and Maintenance

OAA Over-the-Air Activation. See OTA

OAM&P Operations, Administration, Maintenance and Provisioning

OATS Over-the-Air Activation Teleservice. See TIA/EIA-136

OBF Ordering and Billing Forum of ATIS

OC-1 SONET service at 51.84 Mbps. Equivalent to one DS3 (672 DS0)

OC-12 SONET service at 622.08 Mbps. Equivalent to 12 DS3 or 8,064 DS0

OC-18 SONET service at 933.12 Mbps. Equivalent to 18 DS3 or 12,096 DS0

OC-192 SONET service at 9.95328 Gbps. Equivalent to 192 DS3 or 129,024 DS0

OC-24 SONET service at 1.24416 Gbps. Equivalent to 24 DS3 or 16,128 DS0

OC-3 SONET service at 155.52 Mbps. Equivalent to 3 DS3 or 2,016 DS0

OC-36 SONET service at 1.86624 Gbps. Equivalent to 36 DS3 or 24,192 DS0

OC-48 SONET service at 2.48832 Gbps. Equivalent to 48 DS3 or 32,256 DS0

OC-768 SONET service at 38.813 Gbps. Equivalent to 768 DS3

OC-9 SONET service at 466.56 Mbps. Equivalent to 9 DS3 or 6,048 DS0

OC-96 SONET service at 4.97664 Gbps. Equivalent to 96 DS3 or 64,512 DS0

OCDM Optical Code Division Multiplexing

OCH Optical Channel

OCN Operating Company Number. US identifier for a telecom carrier

OCS Online Charging System. Used for real-time charging (e.g. prepaid).

OCSP Online Certificate Status Protocol. An IETF protocol

octet A snooty standards term for byte

ODB Operator Determined Barring

OET US FCC Office of Engineering & Technology

OFA Optical Fiber Gateway

OFDM See OFDMA

OFDMA Orthogonal FDMA

OG Optical Gateway

OHG Operators Harmonization Group. A group of wireless carriers that wants to make CDMA systems work on both ANSI-41 and GSM networks

OLA Optical Line Amplifier

OLC Overload Control

OLI Originating Line Indicator. ISUP parameter that identifies the class of phone (e.g. residential, payphone, hotel/motel)

OLNS Originating Line Number Screening (using LIDB)

OLT Optical Line Termination

OMA Open Mobile Alliance

OMC Operations and Maintenance Center

OMNCS Office of the Manager, NCS

OMT Overhead Message Train (messages transmitted from base station on the analog Control Channel)

ON Optical Network

OPC Originating Point Code. Where an SS7 message came from

OPDU Operation PDU

OpenH323 A project to create an open source implementation of H.323

OPSP Origination Participation Service Provider

OPTS Over-the-Air Programming Teleservice. See TIA/EIA-136

Originating MSC

The first MSC involved in a mobile terminated call. Either a Gateway MSC or the Home MSC

Origination The process of starting a call, usually initiated by dialing digits

ORREQ TIA/EIA-41 OriginationRequest transaction

OSA 3GPP Open Service Access. Enables third parties to use network functionality through an open standardized interface (OSA API)

OSA-AS OSA Application Server

OSA-SCS OSA Control Server

OSF Operations Systems Function

OSI French synonym for ISO

OSPF Open Shortest Path First IP routing algorithm.

OSS(1) Operations Support Subsystem

OSS(2) Operator Services Switch

OTA Over-the-Air programming. Uploads internal mobile tables or software.

OTAF Over-The-Air Activation Function. A specialized MC for performing OTASP and OTAPA

OTAPA Over-The-Air Parameter Administration. A network initiated form of OTA

OTASP Over-the-Air Service Provisioning. A mobile-initiated form of OTA

OTDOA Observed TDOA

overdial The process of dialing a phone number during an established call, when the original number dialed was to access some kind of gateway system. See Roamer Port

OWF One Way Function. A function that is much easier to perform than to invert (i.e. back-calculate). This concept is the foundation of much of modern cryptography

OXC Optical Cross Connect

P P-CSCF Proxy CSCF. First contact point for a terminal within the IMS

P-P PDSN to PDSN interface used to support fast handoff (tunneling of packets from old serving system to new serving system).

P-SCM Proxy SCM

P-TMSI Packet TMSI

PABX See PBX

PAC PPTP Access Concentrator. Concentrates PPP traffic on a dial access platform. See PNS

PACA Priority Access and Channel Assignment. Channels are assigned to mobiles attempting to originate a call in order of priority, rather than first-come, first-served. See PAS

Packet data Data transmitted from multiple users in individually address discrete packets. Compare with CSD

PACS Personal Access Communications System

PAD Packet Assembly/Disassembly

Page The process of telling an MS to prepare for an incoming call

PAMR Public Access Mobile Radio. A wide-area form of PMR that provides group-oriented communications (such as PTT) to the public, rather than being run for a single organization. See SMR.

PAN Personal Area Network. A network that connects personal devices, such as computer, keyboard, mouse, phone and monitor. Also known as Piconet

PANID Previous ANI

PAP Password Authentication Protocol. A simple authentication protocol that sends security information in the clear. Compare with CHAP

Parlay/OSA Open Service Access/Architecture. An API that enables operator and 3rd party applications to make use of network functionality through a set of open, standardised interfaces. Implementations are JAIN SPA, OMG-IDL and WSDL

PAS Priority Access Service. See PACA

PBCCH GPRS Packet Broadcast CCH

PBX Private Branch Exchange. A privately owned switch providing wired and possibly also wireless service for an office, factory, campus, etc.

PC Personal Computer

PCAP UTRAN Positioning Calculation Application Part

PCCCH GPRS Packet Control Channel

PCF Packet Control Function. Obsolete. See PDF

PCG 3GPP Project Coordination Group

PCH Paging Channel

PCI Protocol Capability Indicator

PCIA Personal Communications Industry Association. Rival trade association to CTIA

PCM Pulse Code Modulation

PCMCIA Personal Computer Memory Card International Association

PCN Personal Communications Network. See PCS

PCS Personal Communications System. See DCS, PCS1900

PCS1900 North American PCS frequencies, 1850-1990 MHz. See DCS

PCSC Personal Communications Switching Center. See MSC

PD Packet data

PDA Personal Digital Assistant

PDC Pacific Digital Cellular. A Japanese cellular standard based on GSM operating in the 800 MHz and 1500 MHz frequency bands.

PDC-P PDC Packet network used

PDCP UTRA Packet Data Convergence Protocol

PDD Post-Dial Delay. The delay between dialing and having the call cut through to the party at the other end

PDE Position Determining Entity

PDF Policy Decision Function

PDG PD Gateway. Similar to PDSN.

PDH Plesiochhronous Digital Hierarchy

PDLP PD link protocol

PDN Public Data Network or Packet Data Network

PDP PD Protocol

PDREG Power-Down Registration

PDSN Packet Data Serving Node. Not to be confused with PSDN

PDU Protocol Data Unit

PEAP Protected EAP. A more secure version of LEAP developed by Microsoft and Cisco.

pen register A form of surveillance where dialed digits and time of call are collected

Penetration The percentage of the population of a service area (POP) that have acquired a certain service

PER(1) Packed Encoding Rules. Avoids the TLV overhead of BER and TCAP

PER(2) Packet Error Rate. The fraction of packets that have one or more errors. Compare with BER.

pESN Pseudo ESN. Formed as a SHA-1 extract of the MEID. See also tESN.

Peta Prefix to indicate one thousand trillion (e.g. Peta-bit). Abbreviated P

PH Packet Handler

PHB Per-Hop Behaviour

PHS Personal Handyphone Service. A real success until people found that it was not true cellular service

PI Polling Indicator

PIC(1) Preferred Inter-exchange Carrier Code. Identifies the long distance carrier for a subscriber. Generally national in scope

PIC(2) Point in Call. An IN, WIN, CAMEL term

Piconet See PAN

PIN Personal Identification Number. Used to restrict access to personal services or capabilities

PINT PSTN and Internet Interworking - IETF WG. See RFC 2848

PISN Private Integrated Services Network. Composed of inter-connected PBXs.

PKC Public Key Cryptography. Also known as Asymmetric Key Cryptography

PKCS PKC System

PKE Public Key Encryption

PKI Public Key Infrastructure

PL Physical Layer

Plaintext Unencrypted data. Compare with Ciphertext

PLCM CDMA Private Long Code Mask. A code, derived from the MSs ESN that encrypts voice communications.

PLMN Public Land Mobile Network. A cellular, PCS or 3G wireless network

PM(1) Privacy Mode

PM(2) Personal Mobility

PMN Public Mobile Network. Synonym for PLMN

PMR Professional/Private Mobile Radio. A radio system established to service a single organization or group of related organizations. They usually provide special group communications capabilities, such as PTT. See SMR. Contrast with PAMR

PN(1) Pseudo-Noise. Orthogonal code used to separate CDMA transmissions

PN(2) Project number

PN Sequence A defined repetitive sequence of binary bits, typically quite long. PN sequences are often used to test digital communications systems because they are composed of typical data patterns (as opposed to, say, alternating 1s and 0s) but are nonetheless defined bit-by-bit, so that the correctness of received bits can be determined at the receiver. PN sequences are also used extensively in the channel structure of many wireless technologies such as CDMA.

PNA Presence Network Agent

PNG Portable Network Graphics. A web graphics format using lossless compression (and decompression) and 48 bit color (unlike JPEG). Its proponents believe that it will also replace GIF and TIFF.

PNP Private Numbering Plan

PNS PPTP Network Server. See PAC

PoC Push/Press-to-Talk over Cellular. Refers to systems running over standard cellular systems that emulate the push-to-talk system of iDen and similar systems. See PTT.

POCSAG A paging protocol that runs at 512 or 2400 bps. Compare with FLEX, ReFLEX.

POI Point of Interconnect

Point Code A numeric SS7 address. 24 bits in the NANP, 16 bits in Japan, and 14 bits in most other countries

Pooling The ability to share a block of 10,000 NANP phone numbers between carriers. See ITN and Thousands block pooling

POP(1) Population of a service area. Licenses are often valued based on this

POP(2) Point of Presence. A place where a carrier provides connectivity to its network

POP3 Post Office Protocol Version 3. IETF RFC 1939

Port-in The porting of a number from the perspective of the new service provider. See LNP and WNP

Port-out The porting of a number from the perspective of the old service provider. See LNP and WNP

Portable Block A block of 10,000 NANP directory numbers that contains at least one Ported DN

Portal A fancy name for a web page that provides a single point of entry for a suite of web services

Ported DN A DN that has been ported from one carrier to another. See LNP and WNP

POS(2) Packet over SDH

POS (1) Personal Operating Space. A space about a person or object about 10 meters in radius that envelopes the person. See WPAN

POTS Plain Old Telephone Service (incoming and outgoing calls, but no fancy features)

PPDN Public PDN

PPDR Public Protection and Disaster Relief

PPDU Presentation PDU

PPP(1) Point-to-Point Protocol. IETF RFC 1661. Provides a reliable link to the internet over a single-user facility (e.g. phone line) that can carry several network protocols simultaneously. See PPP, PAP, CHAP

PPP(2) Peripheral Pre-Processor

PPTP Point-to-Point Tunneling Protocol. Allows PPP to be tunneled through an IP network. Uses an enhanced GRE mechanism for flowcontrol and congestion control. Defined in RFC 2637. May be replaced by L2TP

PQoS Position QoS. The desired/required/measured quality of position measuring accuracy and delay

PRACK IETF SIP Provisional Acknowledgement message

PRAMP Power Ramp

PRBS Pseudo-Random Binary Sequence

PRC(1) Premium Rate Charging

PRC(2) Primary Reference Clock

PRC(3) People’s Republic of China

Prepaid wireless

Wireless services paid for in advance, as opposed to monthly billing. Technical challenges limit the services available, such as roaming and international calling

PRI Primary Rate Interface (1.544 Mbps). See T1, DS1

Private long code mask

Used for encrypting TIA/EIA-95 conversations. Based on secret key information

PRL CDMA Preferred Roaming List. A database within an MS that prioritizes the systems that the mobile might encounter while roaming.

PRN Provide Roaming Number

Protocol A specification of the messages used to communicate over one or more Interface

PS(1) Packet Switch(ed)

PS(2) Priority Service. See WPS, PACA

PS(3) Positioning Server.

PSAP Public Service Answering Point. The place where 9-1-1 calls are answered

PSD Power Spectral Density

PSDC WAG Persistent Storage Drafting Committee. A WAP Working Group

PSDN Packet/Public Switched Data Network. Not be be confused with PDSN

PSI PCF Session ID

PSID Private SID. Used to identify a virtual private wireless system (e.g. wireless PBX)

PSK(1) Phase Shift Keying. Information bits are identified by changes in phase of the carrier. Usually, the signal is split into two parts. I is unchanged, and Q is phase shifted by 90 degrees. Phase can be controlled by the amount of each path that is remixed upon output

PSK(2) Pre-Shared Key.

PSMM Pilot Signal Strength Message. Used for CDMA triangulation

PSN Packet Switched Network

PSPDN Packet Switched PDN

PSS 3GPP Packet Streaming Service.

PSTN Public Switched Telephone Network. The 'phone system'.

PSVT Packet-Switched Video Telephony

PTM Point-to-Multipoint (Broadcast)

PTP Point-to-Point

PTT Push To Talk. Pressing a button on a phone initiates communications with a pre-defined group of other users. The system will usually give one radio the ability to transmit, and the remainder can only listen until the button is released or the phone exceeds the maximum time limit on the right to talk.

Public long code mask

Used for encrypting TIA/EIA-95 conversations. Based on the ESN of an MS

PUREG Power-Up Registration

PV Protocol Version

PVC Permanent VC

PVI PV Indicator

PZID Packet Zone ID

Q QAM Quadrature Amplitude Modulation. A method of encoding a digital

symbol in an analog symbol using combinations of phase and amplitude that are modulated at right angles to the main carrier. See 8QAM, 16QAM, 32QAM, 64QAM, 128QAM

QAM/CAP QAM/CAP

QCELP Qualcomm Code Excited Linear Prediction

QoE Quality of Experience. The subscriber's perception of their quality of service.

QoR Query on Release. A method for implementing LNP

QoS Quality of Service. A list of measurable attributes such as bandwidth, delay and jitter that should be met for a specific communications service

QPSK Quadrature PSK used in CDMA. Phase can be in one of four states

QSIG ISDN based signaling inter-PBX protocol.

Quintet A group of 5 security data elements used in AKA. Composed of RAND, expected user response (XRES), Cipher Key (CK), Integrity Key (IK) and network authentication token (AUTN)

R R and R Revise and Resubmit. The usual treatment for a contribution to a

standards committee

R-APDU Response APDU

R-P Interface between a PDSN and a PCF that uses a GRE tunnel to carry user data and signaling messages.

R-SCH Reverse SCH (from MS)

R-SGW Roaming SGW. Interface between SS7 SCCP and MTP to IP protocols

R-UIM Removable UIM

RA Registration Authority

RAB Radio Access Bearer

RAC Routing Area Code. An 8 bit number identifying a routing area with a location aarea

RACF Radio Access Control Function. An IN term

RACH Random Access Channel. Mobiles compete to access this shared Control Channel

Radio Frequency

Electro-magnetic radiation having a frequency in the range used for telecommunications, greater than that of the highest audio-frequency and less than that of the shortest infra-red waves.

Radio Interface The interface between an MS and a BS

RADIUS Remote Authentication Dial-In User Service. An internet user authentication system. See IETF RFC 2138, 2139 and AAA

RAI GSM Routing Area Identification. Composed of LAI + RAC

RAKE A receiver technique which uses several baseband correlators to individually process several signal multipath components. The correlator outputs are combined to achieve improved communications reliability and performance

RAN Radio Access Network

RANAP UTRAN RAN Application Part

RAND Random number used for authentication purposes

RANDBS Random number used for base station challenge authentication operation. See CAVE

RANDC RAND Confirmation. A portion of RAND used to try to confirm the value that was used by an MS during a Global challenge

RANDSSD Random number used for CAVE SSD Update operation

RANDU The random number used for a Unique Challenge

RAO Revenue Accounting Office

RASC Radio Access System Controller. An IN term

RAT Radio Access Technology. Used to distinguish between GPRS and UMTS in 3GPP networks.

Rate Center The location of a phone for billing purposes. Long distance charges are calculated based on the distance between two rate centers (often the switch location). Rate centers and competition combine to cause very inefficient number assignment, because every carrier operating in a

rate center must be assigned at least 10,000 numbers. But, see Pooling

RATI Random ATI. Compare with UATI

RBOC Regional BOC. One of 7 local exchange companies formed from the breakup of AT&T: NYNEX, Bell Atlantic, BellSouth, Southwestern Bell, Pacific Bell, US West and Ameritech

RCF Radio Control Function. An IN term

RD Requirements Document

RDCCH Reverse DCCH

RDF Resource Description Format

RDTC Reverse DTC

RDV Roamer Database Verification (IS-847). Ability of HLR to query VLR database to determine whether information needed to support roamers is correct

REAG Regional EA Grouping. A geographical area (encompassing several EAs) used to license the AWS B, C and E bands.

RECC Reverse Analog Control Channel

Recipient Switch

The switch to which a number has been ported. See LNP

RED Random Early Detection

Reed-Solomon A type of FEC

ReFLEX A two-way paging protocol related to FLEX. Operates at speeds up to 9600 bps inbound and 6400 bps outbound (25 kHz channel) or 25600 bps (50 kHz channel)

Registration The process where an MS informs a system of its presence

Rel(1) Abbreviation for release of a specification (e.g. GSM Rel 5)

REL(2) SS7 ISUP circuit Release message

Release Returning a trunk, transceiver or other telephony resource to the idle list

RES Authentication response. A value calculated from at least a secret key and a random number, that can be used to infer that the respondent is in possession of the secret key, without revealing it.

RETURN RESULT

Message sent to successfully end TCAP transaction

REVAL Recommendations on the Procedures for Evaluation of Radio Transmission Technologies for FPLMTS

Reverse 911 Dialing up all landline phones within a geographical area to deliver a recorded message, e.g. about a weather emergency. This is usually a voluntary service

Revertive dialing

Calling your own phone number. Often used to access a voice mail system

RF Radio Frequency

RFC IETF Request for Comments. Internet standard (well, not officially, but in practice many internet ‘standards’ are still just RFCs)

RFI(1) Request For Information

RFI(2) Radio Frequency Interference

RFID Radio Frequency Identification. A small chip that is designed to allow the identification and tracking of an object (e.g.manufactured item, airline bag).

RFP Request for Proposal

RFU Reserved for Future Use

RIH Rate Input Handler. Puts a price on usage (e.g. a phone call)

Rijndael Encryption algorithm chosen for AES (replacement for DES). Means 'Rhine Valley' in Flemish. Pronounced 'Rain Doll' (while clearing your throat)

RIL3 GSM Radio Interface Layer 3

RIP Routing Information Protocol. Compare with OSPF

RLC Radio Link Control

RLEC Rural LEC

RLH Rate Load Handler. Loads rated transactions into the billing system and monitors the usage limits (e.g. for prepaid, fraud analysis)

RLP(1) Radio link protocol

RLP(2) OMA/3GPP Roaming Location Protocol between SUPL Location Platforms (SLP).

RN Radio Network

RNC Radio Network Controller

RNS Radio Network Subsystem

RNTI Radio Network Temporary Identity. See TMSI

ROA Registered Operating Agency

Roamer A mobile that is present in a system (MSC-V) that is not its home system

Roamer Port A phone number that allows Termination to a Roamer via the MSC-V

ROER Remote Operation Error. See ROSE

ROHC RObust Header Compression (and, if you’re lucky, decompression). RFC 3095. Provides compression of IP, UDP, RTP and ESP headers using W-LSB. In future, compression of TCP, SIP and other header types is also planned. It is more robust than CRTP

ROIV Remote Operation Invoke. See RORJ

RORJ Remote Operation Reject. See ROIV

RORS Remote Operation Result

ROSE Remote Operations Service Element. A message packaging protocol

Router An IP packet switch. Compare with STP

RPC(1) Radio Port Controller. An IN term

RPC(2) Remote Procedure Call. A method of exchanging data between applications running on different machines. Compare with SOAP

RR(1) Radio Resource

RR(2) Resource Record. Basic storage element for DNS

RRC RR Control

RRM RR Management

RRP MIP Registration Reply

RRQ MIP Registration Reply Request

RS Reed-Solomon error correction code

RSA(1) Rural Statistical Area. CGSA for rural cellular systems. Also used for licensing the FCC AWS D band.

RSA(2) Rivest, Shamir and Adleman PKE algorithm. Also the name of a corporation based on commercialization of this algorithm

RSID Residential SID. Used to identify a virtual residential wireless system

RSN Robust Security Network. The long-term security enhancement for WiFi that replaces both WPA and WEP.

RSS Received Signal Strength. A measure of the strength of a radio signal

RSSI Received Signal Strength Indication. Used to determine when a Handoff should be attempted

RSVD Reserved

RSVP IETF Resource Reservation Protocol. RFC 2205. A control protocol for assigning bandwidth to packets based on their desired QoS

RTCP RTP Control Protocol.

RTF Radio Terminal Function. An IN term

RTP(1) ISUP Release to Pivot Capability. Allows a call connected to one switch to be redirected to another by dropping back to an earlier switch to optimize trunking

RTP(2) IETF Real Time Protocol. Used by SIP, among other protocols

RTSP Real Time Streaming Protocol

RTT(1) Radio Transmission Technology candidate for IMT-2000

RTT(2) Round trip time. The time for a message to get from origin to destination and back again. For communications based on the exchange of many small messages this is more important than the actual bandwidth.

RTT(3) Abbreviation for 1XRTT

RVC Reverse analog Voice Channel

RX Abbreviation for receive or receiver

RXP A protocol that bridges ReFLEX networks together. Based on XML, HTTP and TCP/IP. See WCTP

RZ Return to Zero

S S-BCCH SMS BCCH

S-CSCF Serving CSCF. Handles IMS session states

S-SCM Serving SCM

S/N Signal to noise ratio

S/R Emergency services selective router

SA Security Association

SA1 3GPP TSG SA Working Group 1 for Service Specifications.

SA2 3GPP TSG SA Working Group 2 for Architecture Specifications.

SA3 3GPP TSG SA Working Group 3 for Security Specifications.

SA4 3GPP TSG SA Working Group 4 for Codec Specifications.

SA5 3GPP TSG SA Working Group 5 for Telecom Management.

SAAL Signaling ATM Adapatation Layer. Equivalent of MTP layer 2 for ATM networks used to carry SS7 traffic. Includes SSCF, SSCOP and MAAL

SABM Set Asynchronous Balanced Mode

SACCH Slow Associated Control Channel. A control channel that is transmitted at a low bit rate in parallel with digitized voice.

SACH GSM term for SACCH

SAFER Safe And Fast Encryption Routine. Based on IBC

SAIC Single Antenna Interference Cancellation

SAMPS ANSI-136 System Assisted Mobile Positioning through Satellite. TDMA, MS-assisted location determination, using GPS

SAP Service Access Point. Identifies a particular user service, sending and receiving a specific class of data.

SAPI SAP Identifier. Assigned by IANA.

SAR(1) Segmentation and Reassembly

SAR(2) Successive Approximation Converter. Type of analog-to-digital converter

SAR(3) Specific Absortion Rate. Amount of RF energy absorbed (e.g. for RF/health studies)

SASL Simple Authentication and Security Layer. IETF RFC 2222

SAT(1) Supervisory Audio Tone. One of three tones around 6 kHz that are transmitted from a base station to an MS by analog cellular (EIA/TIA-553)

SAT(2) SIM Application Toolkit

SC Steering Committee

SCC(1) SAT Color Code. A slight variation in frequency to limit false SAT

detection

SCC(2) Service Control Code. A 1, 2 or 3 digit code followed by an asterisk (*) used for controlling switch capabilities during a call (e.g. 777*). Compare with FC

SCCP Signaling Connection Control Part. SS7 enhanced routing and identification layer

SCE Service Creation Environment for the Intelligent Network (IN, WIN)

SCEG Smart Card Expert Group. A WAP Working Group

SCEMA Secure Cellular Encryption Module Algorithm

SCF Service Control Function. Most important part of an SCP

SCH(1) CDMA Supplemental Channel. Used for transmitting higher speed data

SCH(2) GSM Synchronisation Channel; downlink only frame synchronisation and identification of base station.

SCID Subchannel Identity

SCM(1) Station Class Mark. Identifies the power class and transmission mode of an AMPS terminal

SCM(2) 3GPP2 Session Control Manager. Manages multimedia sessions. Obsolete. See CSCF

SCP Service Control Point. An SS7 network element used to control call processing (e.g. by providing database or intelligent network services)

SCPT CDMA Service Category Programming Teleservice

SCR Static Conformance Requirements

SCTP Stream Control Transmission Protocol specified in IETF RFC 2960. Similar to TCP, it differs in supporting multiple independent streams of packets which prevents a failure in one stream backing up packets in all streams.

SCVP Simple Certificate Validation Protocol. Allows a simple device to send a certificate to a server for validation. An IETF draft

SDB Short Data Burst

SDCA Indian Short Distance Charging Area

SDCC Supplementary DCC

SDCCH GSM Standalone Dedicated Control Channel.

SDCH See SDCCH

SDF Service Data Function (IN term)

SDFU Sub-rate Digital Facility Unit

SDH Synchronous Digital Hierarchy

SDL Specification Description Language

SDO Standards Development Organization. The TIA and ATIS are SDO's

SDP IETF Session Description Protocol that describes multimedia sessions

for the purposes of session announcement, invitation, and other forms of multimedia session initiation. See SIP

SDR(1) Software-Defined Radio. A radio that can operate in different modes (e.g. frequency bands, modulation schemes) based on the software that is currently loaded and active in the device.

SDR(2) Special Drawing RIghts. A virtual currency used for exchange of billing information between carriers.

SDSL Symmetric DSL. Bit rates are the same in both directions

SDU(1) Selection and Distribution Unit. Part of a base station that contains the voice coders

SDU(2) Service Data Unit

segmentation The process of breaking a long protocol message into pieces that are no longer than the maximum allowed by lower protocol layers. Oh, and reassembling them later!

Sensitivity The ability to receive a radio signal very near to the thermal noise level. The more sensitive the receiver, the lower the required incident radio signal required for acceptable reception.

SerG GSMA Services Group

Serving MSC The MSC currently serving an MS

SESN SIM ESN

SET SUPL Enabled Terminal. Supports the location procedures of SUPL, interacting with the network over the user plane bearer.

Settlement The process of exchanging revenue between telecommunications carriers

SF Superframe

SFI Short File Identifier in a UIM or SIM

SG(1) ITU Study Group

SG(2) Signaling Gateway. Converts an internet protocol to another protocol, e.g. SS7

SG(3) GSMA Security Group

SGCP Simple Gateway Control Protocol. A VoIP call control standard. Also see MGCP

SGML Standardized Generalized Markup Language. The father of XML

SGSN Serving GSN

SGW Signaling Gateway

SHA-1 Secure Hash Algorithm. Produces a condensed representation ('hash') of a string of bits (e.g. protocol message). Because it is computationally infeasible to determine the original text knowing the digest it is useful in authentication algorithms. Because it is also infeasible to find two strings that produce the same digest, it is also useful in digital signing algorithms. See MD5.

SHDSL Single-pair high speed DSL

SID System Identifier. A 15 bit identifier of an AMPS wireless license or system

SIF Signalling Information Field. The payload of an SS7 MTP message

SIG Special Interest Group

Signaling Messages used to control calls, assign resources, maintain and monitor telecommunications systems

SIM(1) GSM Subscriber Identification Module (Smart Card). Compare with UIM

SIM(2) Service Interaction Manager. A WIN concept

SIMPLE SIP for IM and Presence Leveraging

SIN Specification Information Node

SINAD Signal + Noise + Distortion

SIP Session Initiation Protocol. An IETF IP protocol for VoIP (packetized voice) call processing. See SDP.

SIP-AS SIP Application Server

SIP-T Variant of SIP that encapsulates ISUP signaling to provide support for circuit-switched communications

SKey Session Key

SLA Service Level Agreement. A carrier agrees to provide a certain level of service (e.g. availability, bit rate, voice quality) and provide significant discounts if the levels are not met

SLC SUPL Location Center. Coordinates the operations of SUPL in the network.

SLEE Service Level Execution Environment

SLF 3GPP Subscription Locator Function

Slow Fading Fade duration long relative to channel frame length

SLP(1) Service Logic Program

SLP(2) SUPL Location Platform. Consists of an SLC and an SPC.

SLS Signaling Link Selection

SM Session Management

SM-MT Mobile Terminated Short Message

SM-SC Short Message Service Center (see MC)

Smart Card See UIM, SIM

SMCK OTA Secure Mode Ciphering Key. Allows for the encryption of provisioning data that is going to be transmitted over a radio interface

SMDPP TIA/EIA-41 SMS Delivery Point-to-Point message

SMDS Switched Multimegabit Data Service

SME(1) Short Message Entity (SMS terminal)

SME(2) Signaling Message Encryption

SMG Subject Matter Group

SMIL Synchronised Multimedia Integration Language

SMLC Serving MLC

SMPP Short Message Peer-to-Peer Protocol. Promoted by the SMPP Forum

SMR Specialized Mobile Radio. A form of private mobile radio that allows one talker and multiple listeners in a group (e.g. taxi company)

SMS(1) Short Message Service

SMS(2) Service Management System. Communicates number portability (LNP) and pooling information between carriers.

SMS-C GSM SMS Center. See MC

SMSCB See Broadcast SMS

SMSCH SMS Point-to-Point Channel

SMSEG WAP SMS Expert Group

SMTP Simple Mail Transmission Protocol defined in IETF RFC 2821

SMV CDMA Selectable Mode Voice Coder

SN(1) Service Node. A combination of SCP and IP functionality

SN(2) E.164 Subscriber Number

SND See SINAD

SNDCP Sub-Network Dependant Convergence Protocol

SNMP Simple Network Management Protocol. Network management protocol usually used with TCP/IP networks, and others

SNR(1) See S/N

SNR(2) Serial number. The unique 6 digit number assigned to a GSM phone within an IMEI

SOA Service Order Activation. For LNP, this represents an interface between a carrier and the NPAC SMS

SOAP Simple Object Access Protocol. XML based language for exchanging data between internet applications on different machines. Bypasses firewalls by being disguised as XML/HTML. Compare with CORBA and RPC

SOC System Operator Code. Used in IS-136 TDMA digital systems to identify the wireless carrier

SOHO Small Office/Home Office

SoLSA Support of Localized Service Area

SONET Synchronous Optical Network

SoR Statement of Requirements.

SP(1) Signaling Point. An SS7 network node: SCP, SSP or STP

SP(2) ANSI standards proposal number

SPA JAIN Service Provider APIs

SPASM Subscriber Parameter Administration Security Mechanism

SPC SS7 Signaling Point Code. Also PC

SPDU Session PDU

SPI Service Provider Identification

SPINA Subscriber PIN Access

SPINI Subscriber PIN Intercept

SPL Service Programming Lock. A method of preventing a mobile from changing from the service the subscriber has contracted with

SPMC Signaling Point Management Cluster

Spool Simultaneous Peripheral Operations On-Line. Writing a print or other file to a special area of memory or disk so that it can be printed (or otherwise processed) while other computer operations are ongoing.

SPS Serving PS

SQM Subscription Quality of Service Manager

SQN Sequence number (used for authentication/encryption). Its use can prevent replay attacks, where the same information is transmitted by a fraudulent device as by the legitimate device.

SRC WAP Specification Requirements Committee

SRD CTIA Standards Requirement Document

SRES Expected response to authentication challenge for GSM authentication. Compare with AUTHR

SRF Service Resource Function. Most important part of an IP

SRNC Serving RNC

SRNS Serving RNS

SS Supplementary/Supplemental Service

SS7 Signaling System Number 7 (common channel telecommunications packet switching)

SSCF Service-Specific Coordination Function. Maps between SAAL and higher layer protocols (e.g. SS7 MTP Layer 3). This includes responsibility for link changeover and flow control See ATIS T1.645

SSCOP Service Specific Connection-Oriented Protocol. Part of SAAL that provides reliable point-to-point communications with sequencing, retransmission on error, flow control, keep-alive, connection control. See ATIS T1.637.

SSD Shared Secret Data. A secondary key used in most CAVE operations

SSD-A Portion of SSD used for Authentication

SSD-B Portion of SSD used for voice, data and signaling encryption

SSF Service Switching Function. An IN term for a switch

SSID Service Set Identifier. An identifier of an 802.11 network.

SSL Secure Socket Layer. Secures TCP connections (e.g. for m-commerce)

SSN Sub-system number. Along with PC, identifies an SS7 network

application or a virtual SS7 network entity

SSO Single Sign On. Having one set of authentication data to access many services.

SSP Service Switching Point (e.g. MSC). An SS7 SP that contains switching and signaling functions.

ST End of pulsing signal. An MF tone

Stage I The portion of a standard that describes the external behavior of a standard or capability

Stage II The portion of a standard that describes the flow of messages through a network to implement Stage I behavior

Stage III The portion of a standard that completely describes a protocol, to the level of bit encoding of messages and parameters, based on Stage II message flows

STK SIM Toolkit

STM Synchronous transport mode

STP SS7 signaling transfer point (i.e. packet switch). An SS7 SP that provides routing services. Compare with Router

STU-III Secure Telephone Unit - III. US government telephone encryption system

SUA SCCP User Adaptation Layer. Replaces SCCP and M3UA. Resides above SCTP and below the application in an IP telecom signaling protocol stack.

SUPL OMA Secure User-Plane Location architecture for LCS with intelligent, IP-enabled mobile devices.

surveillance Lawfully (hopefully) authorized monitoring of communications

SV See SVN

SVC Switched Virtual (data) Circuit

SVN GSM Software Version Number. A 2 digit code identifying a line of mobiles. See IMEISV

SVP Switched Virtual Path

SWAP Shared Wireless Access Protocol. Being defined by HRFWG. Operates in the 2.4 GHz ISM band. Abandoned in 2003.

SWG 3GPP Sub-Working Group

SYNC Synchronization

Synchronous Data that is transmitted as a regular, precisely clocked, stream of bits. A pattern of bits is used as a filler for times when there is no data to transmit. Compare with Asynchronous

SyncML A standard for synchronizing mobile devices.

Systemic Interference

RF interference within a channel used in a wireless system that emanates from other elements of the system itself, and thus has predictable characteristics. For example, transmissions on the same

channel form other base stations (intended for other mobiles). Contrast with Non-systemic Interference and Intermodulation Interference

T T-BCSM Terminating BCSM

T-SGW Trunk SGW

T1(1) Group of standards committees related mostly to wireline standards, such as SS7, but also North American GSM standards

T1(2) A digital link carrying 24 DS0 channels. Used mostly within North America. Compare with E1

T1A1 Renamed the ATIS Network Performance, Reliability and Quality of Service Committee in 2004.

T1E1 Renamed the ATIS Network Interface, Power, and Protection Committee in 2004.

T1M1 OA&M standards committee for North American wireline networks. Renamed as the ATIS Telecom Management and Operations Committee in 2004.

T1P1 Personal Communications (i.e. US GSM) standards committee for North America. Renamed the ATIS Wireless Technologies and Systems Committee in 2004.

T1S1 SS7 standards committee for North America. Split into the ATIS Packet Technologies and Systems Committee and the Protocol Interworking Committee in 2004.

T1X1 Renamed the ATIS Optical Transport and Synchronization Committee in 2004.

T3 Physical device carrying one DS3 service

TA(1) Terminal Adaptor

TA(2) Timing Advance. An adjustment in the time of cellular transmission based on the distance of a terminal from a base station. This can be used to estimate the distance of a terminal and determine its approximate location.

TAC(1) Total Access Communications. A name used by Motorola in several products, such as TACS, DataTAC

TAC(2) Type Approval Code. 6 digit part of IMEI that is assigned by a central authority (e.g. national telecom regulatory body)

TACS TAC System. Basically AMPS in the 900 MHz frequency band

TADIG GSMA Technology and Documentation Interoperability Group.

Tandem Any switch that is used to receive and route traffic (e.g. phone calls), but neither originates nor terminates them

TAP(1) Transfer Account Procedure. A billing record format used mainly by GSM carriers

TAP(2) Telocator (now PCIA) Alphanumeric Protocol for paging, now also

used for SMS.

TAPS TETRA Adcanced Packet Service. A European data system based on GPRS and EDGE designed to work with TETRA. Ideal data performance is 600 kbps with frequency hopping and 466 kbps without. Defined by ETSI TS 101.962.

TAR Temporary Alternative Routing

Target MSC The destination MSC for an inter-system handoff

TBCD Telephony BCD. Digit 0 is encoded as 10, as on a rotary dial phone

TCAP Transaction Capabilities Application Part. Message packaging standard used by TIA/EIA-41, LNP, 800 and other SS7-based applications. Defined in ANSI T1.114

TCB Telecommunication Certification Body. A national authority for the certification of radio devices.

TCC Telephony Country Code

TCG Trusted Computing Group

TCH Traffic Channel. Often classified as full rate(FR) or half rate (HR)

TCP Transmission Control Protocol. A protocol that provides for reliable delivery of messages over the internet. See UDP and IP

TCP/IP TCP used over IP

TD-CDMA TDD mode of operation for UTRA

TDD(1) Telephone Device for the Deaf. See TTY

TDD(2) Time Division/Domain Duplex. See TDMA

TDES Triple DES. An encryption algorithm with a strength of about 112 bits. See AES, DES.

TDM Time Division Multiplexing. See also TDMA

TDMA Time Division/Domain Multiple Access. Modulation technique used by D-AMPS and GSM

TDOA Time Difference of Arrival. See TOA and OTDOA

TDP Trigger Detection Point. See IN

TDS-CDMA Time Division Synchronization CDMA. Chinese 3G radio access proposal

TDSO CDMA Test Data Service Option

TE Data Terminal Equipment. A personal computer, for example

TEG WAP Telematics Expert Group

Teleservice A telecommunications service provided between two telecommunications terminals (e.g. a call between two phones or a short message between two wireless devices). Contrast with Bearer capability

Tera Prefix to indicate one trillion (e.g. Tera-bit). Abbreviated T

Termination The process of reaching the destination of a call. Not to be confused with Disconnection

tESN An ESN for a phone, that is neither a pESN nor a UIMID

TETRA Terrestrial Trunked Radio. A European PAMR system using 25 kHz channels.

TFO Tandem (or Transcoder) Free Operation. Elimination of the Voice Coder from a digital mobile-to-mobile call (assuming that both mobiles are capable of using the same type)

TFT Traffic Flow Template. Used to determine the QoS that applies to a specific packet.

TG Task Group of ITU-R

Thermal Noise Radio frequency noise associated with thermal activity. At a typical temperature of 300 degrees Kelvin (26.84 degrees Celsius), thermal noise is -174 dBm per hertz, or 114 dBm in a 1 MHz channel.

Thousands block pooling

The ability to share a block of 10,000 NANP phone numbers in groups of 1,000 between carriers. Individual phone numbers within the block can then be ported (using LNP) to other carriers

throughput The actual traffic supported, as opposed to the raw bandwidth. Bandwidth that does not result in throughput may be due to packets containing errors, retransmissions, errorneous routing and many other causes. See goodput and badput

TIA Telecommunications Industry Association. A trade association that, among other things, defines standards for cellular and PCS, specifically AMPS, NAMPS, CDMA and TDMA

TIA-136 ANSI version of the TDMA air interface standard. Replaces IS-136 and TIA/EIA-136

TIA/EIA A prefix for a standard produced by the TIA in association with the EIA

TIA/EIA-124 Wireless call detail and billing record format for online transfer. Replaces IS-124

TIA/EIA-136 ANSI version of the TDMA air interface standard. Replaces IS-136. Replaced by TIA-136

TIA/EIA-41 Wireless intersystem operations standard. Previously called IS-41

TIA/EIA-41-D Intersystem Operations Standard. Replaces IS-41

TIA/EIA-634 A-interface standard between BS and MSC

TIA/EIA-683 OTASP for CDMA

TIA/EIA-93 Wireless-PSTN interface standard. Replaces IS-93

TIA/EIA-95 CDMA air interface standard

TIA/EIA-95-B Third generation CDMACDMA air interface standard. Replaces IS-95

TIFF Tagged Image File Format. Supports up to 24 bit color. Files tend to be large, but high quality. Perhaps because of the file size, it is not supported by many browsers. cf GIF, JPEG, PNG

TIPHON Telecommunications and Internet Protocol Harmonization over Networks

Title III A surveillance that is authorized to collect content (e.g. voice communications. Contrast with pen register and trap and trace

TKIP Temporal Key Integrity Protocol. A modification to WEP that increases security by frequently changing keys.

TL1 Telcordia (formerly Bellcore) MML language for telecommunications network monitoring.

TLDN Temporary Local Directory Number. A number used for routing calls from the Home MSC to MSC-V in ANSI-41. Compare with MSRN

TLLI Temporary Link Level Identity

TLS Transport Layer Security

TLV Tag, Length Value. Encoding of parameters by including an identifier (tag), length (of value) and the actual parameter contents (value). Used by BER and TCAP, for example. cf AVP

TM3 TIA committee for standardization of Terrestrial Mobile Multimedia Multicast. Created in 2005. Also known as TR-47

TMN Telecommunications Management Network. A network management protocol, used to logically define managed objects

TMO Trunked Mode Operation. A cellular-like mode of operation of a PAMR system. Compare with DMO.

TMSI Temporary mobile station identity. Used as a shorter, more private, mobile identifier. Identifies the system that assigned it, and not directly the MS

TMUI GSM term for TMSI

TNRN Terminating Network Routing Number

TOA Time of Arrival. A technique for location a radio by comparing the time of signal arrival at multiple points. Compare with AOA

TON Type of Number

TOS Type Of Service

TPDU Transport PDU

TPP Terminating Party Pays. The mobile pays for airtime, whether it is making or receiving a call. cf CPP

TR(1) 3GPP Technical Report. These are informative, as opposed to TS

TR(2) TIA Technical Review standards committee prefix

TR-45 TIA Standards Committee responsible for AMPS-based cellular and PCS standards, including TDMA and CDMA digital

TR-45.1 TIA analog cellular standards subcommittee

TR-45.2 TIA Standards Subcommittee responsible for intersystem protocols

TR-45.3 TIA TDMA digital cellular/PCS standards subcommittee

TR-45.4 TIA BS/MSC "A" interface standards subcommittee

TR-45.5 TIA CDMA digital cellular/PCS standards subcommittee

TR-45.6 TIA CDPD standards subcommittee

TR-45.7 TIA OA&M cellular standards subcommittee. Now defunct.

TR-47 See TM3

Traffic Channel A portion of a radio channel used to transmit one direction of a digital voice conversation. Compare with Voice Channel

Transcoding Conversion from one voice (or other media format) coder to another. Multiple transcoding operations can seriously reduce the end-to-end quality.

Transparent Data that is, to lower protocol layers, simply a sequenced collection of bits. Good protocol design tries to make all protocol layers transparent to all others, although often violations of this principal are necessary

trap and trace Collection of the identity of a part originating a call for surveillance purposes

TRAU Transcoding Rate and Adaptation Unit

TrFO Transcoding Free Operation. Establishment of a call without a transcoder.

Triplet A group of 3 security data elements used in GSM authentication. Composed of network challenge random number (RAND), expected user response (SRES) and Cipher Key (CK)

TS 3GPP Technical Specification. Normative, as opposed to TR

TSAR Teleservice segmentation and reassembly for TIA/EIA-136

TSB TIA Telecommunications Systems Bulletin. Often used as an addendum or erratum to a published interim standard

TSG Technical Specification Group. Part of the 3GPP and 3GPP2 processes

TSG CN 3GPP TSG for CN standardization

TSG GERAN 3GPP TSG for GSM standardization

TSG N 3GPP2 TSG for inter-system network protocols. Replaced by TSG-X.

TSG RAN 3GPP TSG for W-CDMA standardization

TSG S 3GPP2 TSG for service and system aspects (requirements, architecture, Stage 1 descriptions etc.).

TSG SA 3GPP TSG for defining services and architecture of W-CDMA 3G systems

TSG-A 3GPP2 TSG for the IOS

TSG-C 3GPP2 TSG for the cdma2000 radio interface

TSG-N 3GPP2 TSG for network procotols. Replaced by TSG-X

TSG-P 3GPP2 TSG for packet data protocols. Replaced by TSG-X

TSG-T 3GPP TSG for terminal and UIM standardization

TSG-X 3GPP2 TSG for the core network. Formed by the merger of TSG-N and TSG-P

TSI Time Slot Interchange

TT Translation Type. Defines the type of routing address used by GTT (e.g. E.164 directory number, E.212 IMSI etc.).

TTA Telecommunications Technology Association. Standardizes wireless network protocols in Korea

TTC(1) Telecommunication Technology Committee. Telecommunications standardization in Japan

TTC(2) Terminating Toll Center

TTCN Tree and Tabular Combined Notation. ISO/International Electrotechnical Commission IEC 646-3 is a notation for the specification of tests for communication systems. A TTCN–specified test suite is a collection of various test cases together with all of the declarations and components needed.

TTY A device used by the deaf or hearing-impaired to communicate text messages over telephone systems. It runs at 45.45 bps. See TDD

Tunnel An extra protocol addressing layer used to carry data where the inner addressing layer will not take it. Often used in IP, e.g. as part of Mobile IP or VPN

Tunneling Sending data transparently through a foreign network. Usually implies the use of a larger than optimal number of protocol layers

TUP Telephone User Part. Forerunner protocol to SS7 ISUP

TWG GSMA Terminal Working Group

TX Abbrevation for transmission or transmitter

U U/L Uplink (e.g. from mobile to base station). Compare with D/L.

UA(1) User Agent. An application operating on behalf of a user device (e.g. phone or computer). See MM1.

UA(2) GSM Unnumbered Acknowledge

UAProf WAP UA Profiles Drafting Committee. Or a reference to the profiles that they generate.

UASL Indian Unified Access Services Licence. Replaces CMSP. This allows both GSM and CDMA carriers, as well as other technologies, to be implemented.

UATI Unicast ATI. A 128 bit address for a HRPD device. A 32 bit short version is available for transmission.. The AAA returns the IMSI or MIN to the serving network. Compare with RATI

UCP Universal Computer Protocol. Part of ERMES is an ETSI paging system . The most commonly used operations are: 01 - Call Input Operation; 03 - Call Input With Supplementary Services Operation; Operation 30 - SMS Message Transfer Operation; and Operation 51 - Submit Short Message Operation.

UDH Universal Data Header

UDP User Datagram Protocol. An internet protocol providing basic services only. Compare with TCP

UDR RADIUS Usage Data Record. Captures accounting data for packet data sessions.

UDT SS7 MTP unit data message. Carries a payload of about 250 octet

UDTS UDT service message. Used to send error responses to UDT messages

UE User Equipment (e.g. phone and all peripherals such as USIM)

UEA UMTS Encryption Algorithm. May be null (no encryption) or Kasumi

UGID User Group Identification

UHDM CDMA Universal Handoff Direction Message

UHF Ultra-High Frequency. 300-3000 MHz (used in the US and Canada as television channels 14-83)

UIA UMTS Integrity Algorithm. One possibility is Kasumi

UICC UMTS IC Card

UID User Interactive Dialog

UIM User Identification Module (Smart Card). See SIM

UIMID UIM Identifier. Really just a 32-bit ESN assigned to a device that supports ANSI-136 or CDMA operation. See tESN.

UL Uplink. Radio link in the direction 'up' to network. Compare with DL

ULDCH 3GPP Enhanced Uplink DCH

Um Radio interface between MS and BSS/BSC

UML ETSI Universal Modelling Language

UMTS Universal Mobile Telecommunications System (a 3G initiative). See www.umts-forum.org. It operates in 5 MHz channels at 3.84 Mcps with 200 kHz between channels.

UNI User-Network Interface

UNICODE A text encoding method that, by using more than 8 bits, can code special characters for many languages. Standardized as ISO 10646. Compare with ASCII, EBCDIC and ISO-8859-1

Unique Challenge

A method of encryption using a unique random number (RANDU) as a challenge

Uplink Path from terminal to base-station

UPR CTIA User Performance Requirements document. Now know as SRD

UPT Universal Personal Communications

URI Uniform Resource Identifier. A superset of URL and URN. If an object is on the internet and does not have one of these it really doesn't exist.

URL Uniform Resource Locator. Form of internet address usable by a browser. Of the format "<scheme>:<scheme-specific-part>". http, ftp and mailto are examples of schemes. The remainder of the URL is defined by the scheme, with some restrictions on the characters that can be used. Illegal ASCII characters can be included with the %XX notation, where XX is the two digit hexadecimal value of the

character.

URN Uniform Resource Name

USAT USIM Application Toolkit

USCF User Selected Call Forwarding. Allows an incoming call to be diverted before it is answered, either to a preset number, or to a number specified at the time of diversion. Closely related to AH

USIM User Services Identity Module or Universal Subscription Identity Module. SIM for UMTS. See UIM

USSD GSM Unstructured Supplementary Service Data

Ut The 3GPP interface between the UE and AS.

UTC Universal Coordinated Time (don't ask)

UTM Universal Transverse Mercator.

UTRA Universal Terrestrial Radio Access.

UTRAN Universal Terrestrial RAN. The BS, BTS etc. for W-CDMA/UMTS

UU-SIGNAL User to User Signaling

UWB A radio technology that uses short very high speed bursts of data over short distances. It is controversial because some claim that it can share spectrum with other users, and others claim that it will cause unacceptable interference.

UWC Universal Wireless Consortium. Promotes D-AMPS technologies around the world

UWC/136 TDMA digital cellular/PCS based on the IS-136 or TIA/EIA-136 standards

UWCC Universal Wireless Communications Consortium. Proponent of TDMA digital systems based on UWC/136. Disbanded at the end of 2001.

V V and V Verification and Validation. A committee review of a standard before

formal ballot

VA Validation Authority

VAAA Visited AAA

VAD Voice Activity Detection. A system that not only detects the absence of voice, and prevents transmission of unecessary digitized voice during this time

VAR Value-added Reseller

VAS Value Added Service

VASP VAS Provider. A company that provides a service (e.g. web content) without being the carrier.

VC Virtual Circuit

VCI VC identifier

VDSL Very high speed DSL, providing about 58 Mbit/sec in both directions. Available as asymetric (see ADSL) or symmetric (see SDSL). See VDSL Alliance

VDSL Alliance Promoters of VDSL

VGC Voice Group Call

VGCS Voice Group Call Service

VHE Virtual Home Environment

VHF Very High Frequency. 30-300 MHz (used in the US and Canada as television channels 2-13)

VLAN Virtual LAN. A subset of a LAN where files and services not available to a user are hidden.

VLR Visitor Location Register

VMAC Voice Mobile Attenuation Code

VMS Voice Message System

VMSC See MSC-V

vocoder Voice Coder or codec

VOFDM Vector OFDMA

Voice Channel A radio channel used to transmit one direction of an analog voice conversation. Compare with Traffic Channel

Voice Coder Converts an analog voice signal into a digitally coded representation, and vice-versa. Wireless voice coders often also compress the voice into a bit rate from 8kbps to 13 kbps. Also called codec or vocoder

VoIP Voice over IP

VP(1) Voice Privacy (i.e. encryption)

VP(2) Virtual Path

VPI VP Identifier

VPIM Voice Profile for Internet Mail

VPLMN Visited PLMN

VPM Voice Privacy Mask

VPN Virtual Private Network

VSA RADIUS Vendor Specific Attribute. A field used to transmit data for a particular accounting application (e.g. cdma2000 packet data).

VSELP Vector Sum Excited Linear Prediction

W W-CDMA Physical layer of the FDD mode of operation of UTRA. A ‘European’

version of CDMA and the 3G evolutionary step planned for GSM. Operates in pairs of 5 MHz channels at 3.84 Mcps

W-LSB Window-Based LSB encoding for IP header compression (and decompression). Part of ROHC

W3C World Wide Web Consortium

WAE Wireless Application Environment. See WAP

WAG(1) Wireless Applications Group

WAG(2) WLAN Access Gateway

Walsh codes A group of 2N vectors or words which contain 2N binary elements which with themselves and their logical inverses form a mutually orthogonal set.

WAN Wide Area Network. Compare with LAN, MAN

WAP Wireless Application Protocol. A new protocol that is supposed to provide more efficient internet access from wireless phone. See also WML

WAP W3C WAP - W3C Coordination Committee

WAR WLAN Access Router. Manages traffic into and out of a wireless LAN.

WARC World Administrative Radio Convention

WASP Wireless Application Service Provider

WASU Wireless Access Subscriber Unit

WATM Wireless ATM

WATS Wide Area Telephone Service

WAVE See 802.11p

WBMP Wireless Bit MaP. A WAP graphic format

WCDMA See W-CDMA

WCMP Wireless Control Message Protocol. Protocol for reporting errors and performing loopback testing in WAP. Based on ICMP

WCTP Wireless Communications Transfer Protocol. An interface between internet applications and messaging service providers (e.g. paging carriers). Developed by wctp.org. See RXP

WDM Optical Wavelength Division Multiplexing

WDP Wireless Datagram Protocol. See WAP

WEMT CDMA Wireless Enhanced Messageing Teleservice

WEP Wired Equivalent Privacy. First security system for 802.11 WLAN. Has known security weaknesses in the algorithm and the use of fixed keys. WEP derives a 64 bit RC4 key from a 40 bit AP-specific key and a 24-bit IV that is unique to the session. Compare with WPA

WFQ Weighted Fair Queuing

WG Working Group

WGS-84 World Geodetic System 1984

WI Work Item

WID 3GPP WI Description.

WIF Wireless Interconnect Forum (managed by Telcordia)

WiFi IEEE 802.11b wireless LAN system

WIG WAP Interoperability Group

WIM WAP Identity Module

WiMax IEEE OFDM radio interface.

WIMS Wireless Multimedia Message Service

WIN Wireless Intelligent Network. Protocol with similar goals as IN, AIN and CAMEL

WIN Phase I Supports voice controlled services, incoming call screening and CNAP/CNAR

WIN Phase II Supports billing-related services, including Prepaid and Freephone (i.e. 1-800, including airtime)

WIN Phase III Supports location-based services, such as location sensitive billing and intelligent directory assistance

WIP WIN Implementation of PAS

WIPP Wireless Internet Protocol Partnership

WLA Optical Wavelength Adapter

WLAN Wireless LAN, of which the most popular is WiFi

WLL Wireless Local Loop. See FWA

WML Wireless Markup Language. An HTML-like page description and scripting language, that is an essential part of WAP. Compare with cHTML and XHTML

WMLSc WML Script

WNE Wireless Network Entity

WNO Wireless Network Operator. A carrier

WNP Wireless Number Portability. LNP for wireless phones

WNP Phase I The ability for a switch to route to a ported number in another switch

WNP Phase II The ability for a switch to allow numbers to be ported in or out of its number range

WNP Phase III The ability to support services such as short message service in a number portability environment

WP Working Party

WPA WiFi Protected Access. An enhanced version of WEP that does not rely on a static, shared key.

WPAN Wireless Personal Area Network. Standards are being defined by IEEE 802.15

WPG WAP WIreless Protocols Group

WPS Wireless Priority Service. See PACA, PS, NS/EP

Wr Interface between Proxy AAA and WLAN access network.

WRE Wireless Residential Extension - home base station

Ws Interface between Proxy AAA and Home system AAA.

WSDL Web Service Description Language

WSI Wireless Service Indication

WSP Wireless Session Protocol. See WAP

WTA Wireless Telephony Applications

WTAI WTA Interface

WTB US FCC Wireless Telecommunications Bureau

WTLS Wireless Transport Layer Security. See WAP

WTP Wireless Transaction Protocol. See WAP

WWAN Wireless WAN

www World-Wide Web

Wx Interface between AAA and HSS

WZ1 World Zone 1. An obsolete telephone numbering term for countries identified by country code 1 ( USA, Canada and some Caribbean nations)

X X.25 An ITU/CCITT defined general purpose packet switching protocol

X.500 The ISO directory protocol. See DAP, LDAP, DNS

xDSL Refers to all the DSL variants

XHTML Extensible HTML. A version of HTML defined by XML and designed to be extensible. This may also be the evolutionary path for cHTML and WML

XMAC Expected MAC

XML Extensible Markup Language. A meta-language that can be used to define languages like HTML and WML

XOR Exclusive OR. A boolean operation, often used in cryptography. The exclusive-or of two bits is 1 if they have the same value and 0 if they have different values. This operation has the nice property that no information is lost. For example, (A xor B) xor B = A and (A xor B) xor A = B. Try that on any other boolean operation!

XRES Expected response to authentication challenge. For AKA it is derived from RAND using f2. Compare with AUTHR

XUDT Extended UDT. Supports message segmentation

Y

Z Z.300 An ITU-T series of specifications related to MML

ZBTSI Zero Byte Time Slot Interchange (TSI). Bits 2 through 193 of each DS1 frame are scrambled to minimize the possibility of an all-zero octet. If all zero octets are still found, a group of all-ones is substituted. Due to its complexity this method is not often used.

ZCS Zero Code Suppression. The seventh bit of an all-0 octet is replaced by a 1-bit. Only applicable to voice because there is no way to remove this one bit error.

ZigBee A 'cable replacement' radio technology. Somewhat a competitor to Bluetooth although it is designed more for M2M applications (home, business and inustrial automation). It claims to be cheaper and use less power. It uses unlicensed bands at 2.4 GHz, 915 MHz (US) or 868 MHz (Europe). Data speeds are 20–250 kbps depending on the frequency band used. The communications range is from 10 to 75 meters. Developed by the ZigBee Alliance and standardized as IEEE 802.15.4

ZRP Zone Routing Protocol. An internet routing protocol that focuses on routing updates within a zone.