Acronyms and Abbreviations in Telecommunications

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Acronyms and Abbreviations in Telecommunications 7th edition

InterConnect Communications

Written and published by:

InterConnect Communications Ltd Merlin House, Station Road, Chepstow, Monmouthshire. NP16 5PB United Kingdom Telephone: +44 (0) 1291 638400 Facsimile: +44 (0) 1291 638401 Internet: http://www.icc-uk.com E-mail: [email protected]

Copyright:

©2005 InterConnect Communications Ltd All trademarks acknowledged 7th Edition ISBN 1 870935 34 9

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, by photocopying, recording or otherwise, without the prior permission of the publisher. Readers’ comments and enquiries are invited and should be sent to InterConnect Communications at the above address. The Authors may use or distribute any of the information supplied, for the purpose of updating this booklet or otherwise without any incurring any obligation whatsoever. Every effort has been made to ensure that the information in this booklet is correct at the time of publication. InterConnect Communications Ltd does not assume any responsibility for errors or omissions in respect of this publication. We would like to thank everyone who has contributed terms for this edition.

Foreword

Acronyms and Abbreviations in Telecommunications

1

Welcome to the seventh edition of InterConnect Communications’ guide to Acronyms and Abbreviations in Telecommunications. This handbook is published to assist purchasers, suppliers, administrations and communications network operators in their daily work.

The alphabetical listing of terms covers voice, data, radio spectrum, communications products, services, standards, regulation and regulatory authorities. For this new edition, we have reviewed the entire contents for relevance to the fast-changing electronic communications industry and incorporated a substantial number of additional entries to reflect developments in the sector. Our authors welcome comments and contributions to aid the continued improvement of this publication. I hope you find it useful in your business. Fintan Healy Managing Director

2

A

Acronyms and Abbreviations in Telecommunications

A3

GSM Authentication Algorithm

A8

SM Cipher Key Generating Algorithm (GSM)

A5

GSM Stream Cipher Algorithm

AA

Auto Answer

AAL

ATM Adaptation Layer

AARP

AppleTalk Address Resolution Protocol

AAA AAR

AARTS AAV AB

ABC A-bis

ABM

Authentication, Authorisation, Accounting Automatic Alternate Routing

Automatic Audio Remote Test Set

Alternate Access Vendors

Answer Back

Advanced Broadband Communications BSC-BTS Interface

Asynchronous Balanced Mode (HDLC)

ABR

Available Bit Rate (ATM)

ABS

Alternate Billing Service

ABR

Area Border Router

AC

Access Charge

AC

Authorisation Code

AC AC

Area Code

Access Control (Token Ring FDDI)

AC

Authentication Centre

ACA

Automatic Circuit Assurance

ACA

Australian Communications Authority

Acronyms and Abbreviations in Telecommunications

ACC

Automatic Callback Calling

ACD

Automatic Call Distribution

ACCH ACDS ACE

Associated Control Channel Automatic Call Distribution Systems

Authentication Encryption

ACE

Advanced Communications Experiments

ACF

Advanced Communication Function

ACEK ACITS ACK

Authentication Encryption Key

Advisory Committee on Information Technology Standardisation (SOG-IT) Acknowledgement

ACNA

Access Carrier Name Abbreviation

ACQ

All Call Query (number portability)

ACRE

Authorisation and Call Routing Equipment

ACP

ACR ACS

ACSE

ACTE

ACTOM ACTS ACTS

Access Control Point

Allowed Cell Rate

Asynchronous Communications Server Association Control Service Element

Approvals Committee for Terminal Equipment

Advisory Committee on Technical and Operational Matters (of Inmarsat) Advanced Communications Technology Satellite

Advanced Communications Technologies and Services

ACU

Automatic Calling Unit

A-D

Analogue-to-Digital

AD

ADC

Abbreviated Dialling

Analogue-to-Digital Converter

3

4

ADC

Acronyms and Abbreviations in Telecommunications

Access Deficit Charge or Contribution

ADC

Analogue-to-Digital Conversion

ADCT

Adaptive Discrete Cosine Transform Coding (video coding)

ADCCP ADH

Advanced Data Communications Control Procedures Automatic Data Handling

ADIF

Analogue Digital Interface

ADP

Automatic Data Processing

ADPE

Automatic Data Processing Equipment

ADS

Asynchronous Data Switching

ADU

Automatic Dialling Unit

AECMA

Association Européenne des Constructeurs de Matériel Aerospatial (European Association for the Construction of Aero-Space Equipment)

ADM ADPCM ADPSSO ADSL ADX

Add Drop Multiplexer

Adaptive Differential Pulse Code Modulation Automatic Data Processing System Security Officer

Asymmetric Digital Subscriber Line

Automatic Data Exchange

AECN

Alternate Exchange Carrier Name (US)

AEROM

Electrically Alterable Read Only Memory

AENOR AF

AFC AFC AFE

Associación Espanola de Normalización (Standards Association Spain) Audio Frequency

Area Frequency Coordinator

Automatic Frequency Control Analogue Front End

Acronyms and Abbreviations in Telecommunications

AFIPS

American Federation of Information Processing Societies

AFNOR

Association Française de Normalisation (Standards Association France)

AFMS

AFUTT AGC

AGCH

AGCOM

Administrative Frequency Management System

Association Française des Utilisateurs du Téléphone et des Télécommunications (French Telegraphs and Telephone Users’ Association)

Automatic Gain Control Access Grant Channel

Autorità per le Garanzie nelle Comunicazioni (Italy)

AGE

Aerospace Ground Equipment

AH

Authentication Header (IPSec security protocol)

AGRAS

Air-Ground Radiotelephone Automated Service

AI

Artificial Intelligence

AIM

Ascend Inverse Multiplexing

AIM AIM AIN

AIO

AIOD AIP

Amplitude Intensity Modulation

Advanced Informatics for Medicine (Application Programme of DG XIII/F)

Advanced Intelligent Network

Asynchronous Input/Output

Automatic Identification of Outward Dialling Application Infrastructure Provider

AIP

Advanced Information Processing

AIS

Automated Information System

AIP AIS

AITS

Advanced Infrastructure Planning

Alarm Indication Signal

Acknowledged Information Transfer Service (ITU-T)

5

6

Acronyms and Abbreviations in Telecommunications

AJ

Anti-Jamming

ALBO

Automatic Line Build Out

ALC

Automatic Load Control

AL

ALC ALE ALE

ALEC

Access Line

Automatic Level Control

Automatic Link Establishment

Approval Liaison Engineer (UK)

Alternative Local Exchange Carrier (US)

ALI

Automatic Location Information

ALU

Arithmetic and Logic Unit

ALI AM

AM/PM/VSB AMA

AMADNS AMC AME AME

Analogue Line Interface Amplitude Modulation

Amplitude Modulation/Phase Modulation/Vestigial Sideband Automatic Messaging Accounting AMA Data Networking System

Administrative Management Complex Amplitude Modulation Equivalent

Automatic Message Exchange

AMI

Alternative Mark Inversion

AMPSSO

Automated Message Processing System Security Officer

AMPS

American Mobile Phone System (analogue cellular)

AMR

Adaptive Multi Rate

AN

Annunciator

AMTS ANACOM

Automated Maritime Telecommunications System

National Communications Authority (Portugal)

Acronyms and Abbreviations in Telecommunications

ANATEL

Agência Nacional de Telecomunicações do Brasil (Brazil)

ANC

All Number Calling

ANL

Automatic Noise Limiter

ANI

ANM ANR

Automatic Number Identification (ISDN) Answer Message

Automatic Network Routing

ANRC

National Regulatory Authority of Romania

ANRTI

National Regulatory Agency in Telecommunications and Informatics (Moldova)

ANRT

ANS ANS

Agence Nationale de Réglementation des Telecommunications (Morocco) American National Standard Advanced Network Services

ANSI

American National Standards Institute

AOA

Angle of Arrival

ANT AOC

ADSL Network Terminator

All Ones Code

AOC

Advice of Charge

AP

Attendant Position

AOS AP

Alternative Operator Services Anomalous Propagation

AP

Access Point (UPT)

APA

Access Provider Architecture

AP

Application Pilot

APC

Adaptive Predictive Coding

APDU

Application Protocol Data Unit

APCM

Adaptive Pulse Code Modulation

7

8

Acronyms and Abbreviations in Telecommunications

API

Application Programming Interface

APL

Analogue Private Line

APLT

Advanced Private Line Termination

APK APL

APNSS

Amplitude Phase-Shift Keying

Average Picture Level

Analogue Private Network Signalling System

APON

ATM Passive Optical Network

APPC

Advanced Program-to-Program Communications

APS

Automatic Protection Switching

APP

APPN APT APT

Applications Portability Profile

Advanced Peer-to-Peer Networking

Application Pilot Transfer (Group) Telephony Applications System

AR

Alternative Recall

AR

Alternate Route

AR ARA

ARD

ARDIS ARE

ARESEP ARIN

Access Rate

Access Registration Point (UPT) Automatic Ring Down

Advanced Radio Data Information Service

Autorité de Régulation (Mauritania)

Autoridad Reguladora de los Servicios Públicos (Costa Rica)

American Registry for Internet Numbers

ARINC

Aeronautical Radio Incorporated (Aviation)

ARP

Address Resolution Protocol

ARM

Asynchronous Response Mode (HDLC)

Acronyms and Abbreviations in Telecommunications

ARPU ARPT

ARPTC ARQ ARS

ARSR ART

Average Revenue Per User

Autorité de Régulation de la Poste et des Telecommunications (Algeria)

Autorité de Régulation de la Poste et des Télécommunications du Congo ( DR Congo)

Automatic Repeat Request Automatic Route Selection

Air Route Surveillance Radar

Audible Ringing Tone

ART

Autorité de Régulation des Telecommunications (France)

ART&P

Autorité de Réglementation des Secteurs de Postes et Télécommunications (Togo)

ART

ARTEL ARTEL ARU ARU AS AS AS

ASAM ASCI

ASCII

ASCU ASI

ASIC

Agence de Régulation des Télécommunications (Senegal) Agence de Régulation des Télécommunications (Gabon)

Autorité Nationale de Régulation des Télécommunications (Burkina Faso) Audio Response Unit Alarm Relay Unit Analogue Signal

Answer Supervision Anti Spooling

ATM Subscriber Access Multiplexer

Advanced Speech Cal Items

American Standard Code for Information Interchange Agent-Set Control Unit ATM Service Interface

Application-Specific Integrated Circuit

9

10

ASK

Acronyms and Abbreviations in Telecommunications

Amplitude Shifting Key

ASN

Auxiliary Signal Network

ASN.1

Abstract Syntax Notation 1 (ISO)

ASN

ASOG ASP ASP ASP

ASR

ATM Switching Network

Access Service Ordering Guidelines Adjunct Service Point

Application Service Provider

Advanced Speech Processor

Airport Surveillance Radar

ASR

Automatic Send and Receive

ASR

Automatic Speech Recognition

ASR ASR

Access Service Request Answer:Seize Ratio

ASTIC

Anti-Sidetone Induction Coil (Circuit)

AT

Attentuation

AT

Assistive Technology

AT&T

American Telephone and Telegraph Corporation

ASVD AT AT

ATB

ATC

ATCI ATD

ATDM

ATDMA

Analogue Simultaneous Voice and Data

Access Tandem

Asynchronous Transfer Mode All Trunks Busy

Adaptive Transform Coding

Agence des Télécommunications de Côte d’Ivoire Asynchronous Time Division Switching

Asynchronous Time Division Multiplexing

Advanced Time Division Multiple Access

Acronyms and Abbreviations in Telecommunications

ATE

Automatic Test Equipment

ATH

ATM Transmission Hierarchy

ATE

ATIS

Automatic Telephone Exchange Alliance for Telecommunications Industry Solutions

ATIS

Automatic Transmitter Identification System

ATM

Asynchronous Transfer Mode

ATM ATM

ATMM ATS

ATSC ATU

Active Traffic Management Automated Teller Machine

ATM Management Process

ATM Transmission System

Advanced Television Systems Committee

ADSL Transmission Unit

ATU-C

ADSL Transmission Unit, Central

ATRP

Telecommunications, Broadcasting and Post Agency (Slovenia)

ATU-R

ADSL Transmission Unit, Remote

AU

Alternative Use

AUC

Authentication Centre

AUP

Acceptable Use Policy

AU

AUI

AUSM

AUTODIN

AUTOSEVOCOM AUTOVON

Adaptation Unit

Attachment Unit Interface ATM User Service Module

Automatic Digital Network

Automatic Secure Voice Communications Network Automatic Voice Network

11

12

AVD

Acronyms and Abbreviations in Telecommunications

Alternate Voice Data

AVI

Audio Video Interleave

AVM

Audio Visual Management

AVM AW

AWG

AWGN AXE

ATM Voice Multiplexer

Administrative Weight

American Wire Gauge

Additive White Gaussian Noise

Automatic Cross-Connection Equipment (also known as ACE)

B

Acronyms and Abbreviations in Telecommunications

B2B

Business-to-Business

B3ZS

Binary/Bipolar Three Zero Substitution (line-code)

B2C

B6ZS B8ZS

Business-to-Consumer

Binary 6-Zero Substitution (line-code) Binary 8-Zero Substitution (line-code)

BA

Balanced Asynchronous (HDLC)

BABT

British Approvals Board for Telecommunications

BA

BACP

Basic Access

Bandwidth Allocation Control Protocol (PPP ISDN)

BAIC

Barring of All Incoming Calls

BAOC

Barring of All Outgoing Calls

BBS

Bulletin Board Service

BALUN BAP

BBSK Bc

BCA

Balanced, Unbalanced Device Bandwidth Allocation Protocol Binary Phase Shift Keying

Committed Burst

Bhutan Communications Authority

BCC

Block Check Character

BCD

Binary-Coded Decimal

BCF

Budget Cross-Flow Model

BCI

Bit-Count Integrity

BCCH B-CDMA BCH

Broadcast Control Channel Broadband Code Division Multiple Access

Bose-Chaudhuri-Hocquenghem (forward error correction technique)

13

14

BCLB

Acronyms and Abbreviations in Telecommunications

Broadband Connectionless Bearer Service (ATM)

BCOB

Broadband Connection-Oriented Bearer Service (ATM)

Bd

Baud

BDF

Building Distribution Frame

BCPN BDCS

Business Customer Premises Network

Broadband Digital Cross-Connect System

BDSL

See VDSL

BECN

Backward Explicit Congestion Notification

BDT

B-ED

BEMS BEP

Telecommunication Development Bureau of the ITU

Best-Effort Delivery

Business Exchange Measured Service

Back-End Processor

BER

Basic Encoding Rules

BER(T)

Bit Error Rate (Test)

BEX

Broadband Exchange

BFWA

Broadband Fixed Wireless Access

BER

BETRS

BFO Beat BH

BHCA

Bit Error Rate

Basic Exchange Telecommunications Radio Service

Frequency Oscillator

Busy Hour

Busy Hour Call Attempts

BICC

Bearer Independent Call Control

BIH

International Time Bureau

B-ICI

BIOS BIP

Broadband Intercarrier Interface (ATM) Basic Input-Output System Bit Interleaved Parity

Acronyms and Abbreviations in Telecommunications

BIPT

B-ISDN

Belgian Institute for Posts and Telecommunications

Broadband Integrated Services Digital Network

BIT

Built-In Test

BIU

Bus Interface Unit

BLEC

Building Local Exchange Carrier (US)

BLOB

Binary Large Object

BNI

Broadband Network Interface

BNN

Boundary Network Node

BOC

Bell Operating Company (USA)

BOOTP

Bootstrap Protocol

BITE B-LE

BLER(T) BLSR BNM BNS

BONDING BORSCHT

Built-In Test Equipment

Broadband Local Exchange (B-ISDN)

Block Error Rate (Test)

Bidirectional Line Switch Ring

Broadband Network Module

Broadband Network Service

Bandwidth On Demand Interoperability Group Battery supply, Overvoltage protection, Ringing current, Supervision, Coding, Hybrid conversion, Testing

BOT

Build-Operate-Transfer Agreement

BP

Bypass

BPDU

Bridge Protocol Data Unit

BP BP

BPI

BPSK

Band Pass

Breakeven Point

Baseline Privacy Interface

Binary Phase Shifting Key

15

16

Acronyms and Abbreviations in Telecommunications

BPV

Bipolar Violation

BQB

Bluetooth Qualification Body

BR

Radiocommunication Bureau

BPVR BQP

BRA

BRAS

Bipolar Violation Ratio

Bluetooth Qualification Programme Basic Rate Access

Broadband Access Server

BRC

Block Redundancy Check

BRI

Basic Rate Interface (ISDN)

BRLU

Broadband Remote Line Unit

BS

Bearer Service

BSA

Basic Serving Arrangement

BSC

Base Station Controller

BSE

Basic Service Element

BRF

BRITE BS BS

BSA BSC BSGL BSI

BSIC BSP BSP BSS

Bridge Relay Function

Basic Rate Interface Transmission Equipment Base Station Bellset

Business Segmented Accounts

Binary Synchronous Communication Branch Systems General Licence (UK)

British Standards Institute

Base Transceiver Station Identity Code Bell System Practice (US) Building Service Provider

Base Station System / Subsystem

Acronyms and Abbreviations in Telecommunications

BSS

Basic Synchronised Subset

BSS

Billing Support System

BSS

Business Support System

BSS BSSMAP

Broadband Switching System Base Station Systems Management Application Part

BT

Busy Tone

BT

British Telecommunications PLC

B-TA

Broadband Terminal Adapter (B-ISDN)

BT BT

BTA

BTAM B-TE

Block Terminal

Burst Tolerance (ATM)

Botswana Telecommunications Authority

Basic Telecommunications Access Method

Broadband Terminal Equipment (B-ISDN)

BTN

Billing Telephone Number

BTO

Build-Transfer-Operate (see also BOT)

BTNR/BTR BTRC BTS

BUS BVI BW

BXM

British Telecom Network Requirement

Bangladesh Telecommunication Regulatory Commission Base Transceiver Station Terminal

Broadcast and Unknown Server

Bridge Group Virtual Interface

Bandwidth

Broadband Switch Module

17

C

18

C/kT

Acronyms and Abbreviations in Telecommunications

Carrier-to-Receiver Noise Density

C/O

Cut-Off

CA

Call Appearance

CAA

Civil Aviation Authority (UK)

CAC

Carrier Access Code

CACS

Centralised Alarm Control System

C/S CA

CABS CAC

CAD CAE CAF CAI

CALC

CALEA CAM CAM

CAMA

CAMEL

Client/Server

Certification Authority

Carrier Access Billing System

Connection Admission Control (ATM) Computer Aided Design

Computer-Aided Engineering Controllable ATM Fabric

Common Air Interface

Customer Access Line Charge

The Communications Assistance for Law Enforcement Act (US) Computer Aided Manufacturing

Content Addressable Memory

Centralised Automatic Message Accounting

Customised Applications for Mobile Network Enhanced Logic

CAN

Campus Area Network

CAN

Cosmopolitan Area Network

CAN

Competitive Access Network

Acronyms and Abbreviations in Telecommunications

CAP

CAMEL Application Protocol

CAP

Competitive Access Provider

CAP CAP

CAPEX

Carrierless Amplitude Modulation/Phase Modulation

Customer Administration Panel Capital Expanditures

CAPI

Common ISDN API

CARS

Cable Antenna Relay Services

CAPS CAS

Common ISDN API Service

Channel Associated Signalling

CAS

Centralised Attendant Service

CASE

Computer-Aided Software Engineering

CAS

Cordless Access Service

CASE

Computer Aided System Engineering

CAT

Carrier Access Tariff

CASP

CATscan CATV

Communications Application Service Provider

Computed Axial Tomodensitometry Scanner

Cable Television / Community Antennae Television

CAU

Controlled Access Unit (Token Ring)

CAZ

Communications Authority of Zambia

CAVE CB

Cellular Authentication and Voice Encryption

Cell Broadcast

CB

Central Battery

CB

Citizens Band

CB CBAC

C-BAT

Channel Bank

Context-Based Access Control Cost-Benefit Analysis Toolkit

19

20

CBDS

Acronyms and Abbreviations in Telecommunications

Connectionless Broadband Data Service (ETSI)

CBI

Cross-Border Interconnect

CBRA

Constant Bit-Rate Adapter

CBS

Common Base Station

CBR CBS

CBX CC

Constant Bit Rate (ATM) Central Battery Signalling

Computerised Branch Exchange

Common Carrier (US)

CC

Cost Component

CCA

Carrier-Controlled Approach

CC

CCA CCB

Cross-Connect

Current Cost Accounting

Call Control Block

CCB

Coin Collecting Box

CCC

Clear Channel Capability

CCD

Charge Coupled Device

CCBS CCCH CCF

CCH CCK

CCIR CCIR CCIS

Completion of Calls to Busy Subscribers Common Control Channel

Call Control Function

Connections per Circuit per Hour

Communications Commission of Kenya

Comité Consultatif International de Radiodiffusion (International Radiodiffusion Consultative Committee)

Comité Consultatif International des Radiocommunications (Consultative Committee on International Radiocommunications) Common Channel Interoffice Signalling

Acronyms and Abbreviations in Telecommunications

CITC

CCITT CCL

Communication and Information Technology Commission (Saudi Arabia) Comité Consultatif International Télégraphique et Téléphonique (Consultative Committee on International Telegraphy and Telephony)

Continuous Communications Link

CCLC

Carrier Common Line Charge

CCR

Common Control Redundancy

CCS

Call Connect System

CCP

CCR

Calling Card Platform

Customer Controlled Reconfiguration

CCS

Common Channel Signalling

CCSA

Common Control Switching Arrangement

CCS

CCSS6 CCSS7

Hundred Call Seconds per Hour

Common Channel Signalling System No.6

Common Channel Signalling System No.7

CCT

Circuit

CCU

Common Control Unit

CD

Call Deflection

CCTV CCW CD

CD ROM

Closed-Circuit Television

Cable Cutoff Wavelength Carrier Detect

Compact Disc Read Only Memory

CD

Collision Detection (LAN)

CDAA

Circularly Disposed Antenna Arrays

CD

CDC

Compact Disc

Call Directing Code

21

22

Acronyms and Abbreviations in Telecommunications

CDC

Control Data Corporation

CDF

Channel Definition Format

CDDI CDF CDF

CDMA CDO

CDPD

CDPSK

Copper Distributed Data Interface Combined Distribution Frame

Cumulative Distribution Function Code Division Multiple Access

Community Dial Office

Cellular Digital Packet Data

Coherent Differential Phase-Shift Keying

CDR

Call Detail Record

CDU

Central Display Unit

CDVT

Cell Delay Variation Tolerance

CDT

CDV C-E CE CE

CEB

Control Data Terminal Cell Delay Variation

Communications-Electronics Conditioning Equipment

Conformité Européenne (European conformity mark)

Comité Electrotechnique Belge (Electrotechnical Committee Belgium)

CEC

Commission of the European Communities

CEI

Comparably Efficient Interconnection

CELEX

European Community Legislation Database

CEI

CEIR

CELP

Comitato Electrotecnico Italiano (Electrotechnical Committee Italy) Central Equipment Identity Register

Code Excited Linear Prediction Compression

Acronyms and Abbreviations in Telecommunications

CENELEC

CENTREX CEP

CEPT CER

CERN CERT CES CFA

Comité Européen de Normalisation Electrotechnique (European Committee for Standardisation and European Committee for Electrotechnical Standardisation) Central Office Exchange (PBX-like Service)

Circular Error Probable

Conférence Européenne des Postes et Télécommunications (European Conference of Post and Telecommunication Administrations)

Cell Error Ratio

Centre Européen pour la Recherche Nucléaire (European Centre for Nuclear Research) Computer Emergency Response Team

Circuit Emulation Service

Carrier Facility Assignment

CFB

Call Forward Busy

CFNR

Call Forward No Reply

CFE

CFR

CFRAD CFS

Contractor-Furnished Equipment Code of Federal Regulations (US) Cisco Frame Relay Access Device

Common Functional Specifications

CGI

Common Gateway Interface

CHAP

Challenge Handshake Authentication Protocol

CGSA

Cellular Geographical Service Area

ChR

Channel Reliability

CI

Computer Interconnect

CI

CIAS CIC

23

Cell Identity

Circuit Inventory and Analysis System

Carrier Identification Code

24

Acronyms and Abbreviations in Telecommunications

CIC

Content Indicator Code

CID

Caller Identification

CICS CID CID

CIDR

Customer Information Control System Channel ID

Craft Interface Device Terminal

Classless Inter-Domain Routing

CIF

Common Intermediate Format

CIGREF

Club Informatique des Grandes Entreprises Françaises (IT Society for major French companies)

CIFAX CILE CIM CiR

CIR CIR

CISPR CIT

Ciphered Facsimile

Call Information Logging Equipment Computer Integrated Manufacturing Circuit Reliability

Channel Impulse Response

Committed Information Rate

International Special Committee on Radio Interference

Computer Integrated Telephony

CIX

Commercial Internet Exchange

CLASS

Custom Local Area Signalling Service

CL

Connectionless

CLAW

Common Link Access for Workstations

CLEC

Competitive Local Exchange Carrier

CLI

Command Language Interpreter

CLE CLI CLI

Customer Local Equipment

Calling Line Identity/Identification Command Line Interface

Acronyms and Abbreviations in Telecommunications

CLID

Calling Line Identification (ISDN CLASS)

CLIR

Calling Line Identification Restriction

CLNS

Connectionless Network Service (ISO ITU-T)

CLR

Cell Loss Ratio

CLIP

CLNP CLP CLS

CLTS CM CM

CMA CMA

Calling Line Identity Presentation

Connectionless Network Protocol (ISO ITU-T) Cell Loss Priority

Call Logging System

Connectionless-Mode Transport Service

Communications Management

Configuration Management

Communications Management Association Construction and Maintenance Agreement

CMC

Coherent Multi Channel (optical transmission)

CMIP

Common Management Information Protocol

CMI

CMIS

CMISE CMNS

Coded Mark Inversion

Common Management Information Service

Common Management Information Service Element (ISO) Connection-Mode Network Service

CMOS

Complementary Metal Oxide Semiconductors

CMRR

Common-Mode Rejection Ratio

CMR

CMRS CMT CMT

25

Cellular Mobile Radio

Commercial Mobile Radio Service

Comisión del Mercado de las Telecomunicaciones (Spain) Connection Management

26

CMTS

Acronyms and Abbreviations in Telecommunications

Cable Modem Termination System

CN

Core Network

CNAE

Customer Network Access Equipment

CNA

CNAM

Change of Number Announcement Caller Name

CNC

Comisión Nacional de Comunicaciones (Argentina)

C-Net

Analogue Cellular System Standard

CNCA

Carrier Non-Compatible Applications

CNI

Calling Number Identification

CNM

Customer Network Management

CNI

CNMS

Change of Number Interception

Customer Network Management System

CNR

Carrier-to-Noise Ratio

CO

Central Office

CNS CO

CO FRAD COAM COAX

Complementary Network Service

Call Office

Central Office Frame Relay Access Device

Customer Owned and Maintained Equipment

Coaxial Cable

COBOL

Common Business-Oriented Language

CODEC

Coder/Decoder

COFDM

Coded Orthogonal Frequency Division Multiplex

CoC

CODIT

COFETEL CTU

Certificate of Conformity

Code Division Test Bed

Comisión Federal de Telecomunicaciones (Mexico) Czech Telecommunication Office

Acronyms and Abbreviations in Telecommunications

COG

Centralised Ordering Group

COLP

Connected Line Identification Presentation

CO-LAN

Central Office-Based Local Area Network

COLR

Connected Line Identification Restriction

COMJAM

Communications Jamming

COMINT compandor

COMPUSEC ComReg Comsat

COMSEC

Communications Intelligence Compressor-Expander Computer Security

Commission for Communications Regulation (Ireland) Communications Satellite Corporation

Communications Security

CON

Concentrator

CONATEL

Comisión Nacional de Telecomunicaciones (Honduras)

CONATEL

Comisión Nacional de Telecomunicaciones (Venezuela)

CONATEL CONATEL CONEX CONP CONS

Consejo Nacional de Telecomunicaciones (Ecuador)

Comisión Nacional de Telecomunicaciones (Paraguay)

Connectivity Exchange

Connection-Oriented Network Protocol

Connection-Oriented Network Service

COO

Cell of Origin

COPS

Common Open Policy Service

COP

Code of Practice

CORBA

Common Object Request Broker Architecture (OMG)

COSINE

Cooperation for Open Systems Interconnection Networking in Europe (EUREKA-8)

CoS

Class of Service

27

28

COST

Acronyms and Abbreviations in Telecommunications

Cooperation for R&D in Science and Technology

COT

Central Office Terminal

COT

Customer Office Terminal

COT CP

CPAF

CPAS

Continuity Test (SS7) Common Practices

Customer Premise Access Facility Cellular Priority Access Services

CPB

Cell Priority Bit

cPCI

Compact Peripheral Component Interconnect

CPCS

Common Part Convergence Sublayer

CPC

CPCS CPE

Calling Party Category

Call Processing Control System

Customer Premises Equipment

CPI-C

Common Programming Interface for Communications

CPN

Customer Premises Network

CPS

Carrier Pre-Selection Service

CPSS

Control Packet Switching System

CPN CPP CPS

CPT

Calling Party Number Calling Party Pays

Cycles per Second (Hertz)

Compatibility Test

CPU

Central Processing Unit

CQ

Custom Queuing

CR

Channel Reliability

CPU CQL

Computing and Processing Unit

Card Query Language

Acronyms and Abbreviations in Telecommunications

CR

Circuit Reliability

CRA

Communications Regulatory Agency (Bosnia and Herzegovina)

CRA CRAFT CRAG

Call Routing Apparatus

Cooperative Research Action For Technology

Cellular Radio Advisory Group

CRC

Communications Regulation Commission (Bulgaria)

CRC

Cyclic Redundancy Code

CRC CREDFACS CRIMP

Communications Regulatory Commission (Mongolia) Conduit, Raceway, Equipment Ducts, and FACilitieS. (cabling infrastructure elements) Cross Impact Model

CRITICOM

Critical Intelligence Communications

CROM

Control Read-Only Memory

CRM CRS CRS

CRT CRT CRT CRT CRTC CS CS CS

Customer Relationship Management

Channelised Reserved Services Customer Reservation System

Cathode Ray Tube

Comisión de Regulación de Telecomunicaciones (Colombia)

Comité de Régulation des Télécommunications (Mali)

Connexion au Réseau Terrestre (French switching equipment)

Canadian Radio-Television and Telecommunications Commission Carrier Selection

Carrier System

Circuit Switched

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30

CS1 CS2

CSA CSA CSA

Acronyms and Abbreviations in Telecommunications

Capability Set 1

Capability Set 2

Called Sub Answered

Canadian Standards Association Carrier Serving Area

CSC

Carrier Selection Code

CSC

Common Signalling Channel

CSD

Circuit Switched Data

CSC CSCW CSDN CSDN

Circuit-Switching Centre

Computer Supported Cooperative Work Circuit Switched Data Network

Circuit Switched Digital Network

CSE

CAMEL Service Environment

CSI

Called Subscriber Identification

CSI

Carrier Scale Internetworking

CSM

Communications Services Management

CSF CSI CSI

CSMA

CSMA/CA CSMA-CD CSPDN

Customer Service Function

CAMEL Service Indicator

Customer-Sited Interconnection Carrier Sense Multiple Access

Carrier Sense Multiple Access with Collision Avoidance (LAN) Carrier Sense Multiple Access with Collision Detection Circuit Switched Public Data Network

CSR

Customer Service Representative

CSU

Channel Service Unit

CSTA

Computer Supported Telephony Application

Acronyms and Abbreviations in Telecommunications

CSU

Circuit Switching Unit

CSV

Circuit Switched Voice

CSU

Customer Service Unit

CT

Call Transfer

CT

Cordless Telecommunications Mobility

CT CT

Conformance Test

Cordless Telephone

CT

Cross Talk

CT-2

Second Generation Digital Cordless Telephone

CT-1 CTC

CTD CTE CTI

European Analogue Cordless Telephone System

Call Termination Charge Cell Transfer Delay

Channel Translation Equipment

Computer Telephony Integration

CTIA

Cellular Telecommunications Industry Association

CTO

Commonwealth Telecommunications Organisation

CTR

Common Technical Regulations

CTN

C-TPS CTS CTS

CTU

Corporate Telecommunication Network Cut-Through Packet Switching

Clear to Send / Clear to Transmit

Conformance Testing Service

Circuit Terminating Unit

CU

Control Unit

CVD

Chemical Vapour Deposition

CUG CVSD

Closed User Group

Continuously Variable Slope Delta Modulation

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32

cw

Acronyms and Abbreviations in Telecommunications

Carrier Wave

cw

Composite Wave

CW

Call Waiting

cw

CX cxr

Continuous Wave Composite Signalling

Carrier

D

Acronyms and Abbreviations in Telecommunications

D/A

Digital-to-Analogue

DA

Demand Analysis

DAA

Data Access Arrangement

D/L DA

DAB

Downlink

Destination Address (LAN) Digital Audio Broadcasting

DAC

Dual Attached Concentrator

DAI

Digital Audio Interface (104 kbit/s)

DAM

Dynamic Amplitude Modulation

DACS DAL

Digital Access Cross Connect Service

Direct Access Line

DAMA

Demand Assigned Multiple Access

DAP

Demand Access Protocol

D-AMPS DARPA DAS

Digital AMPS (also known as IS-136)

Defense Advanced Research Projects Agency (US)

Directory Access System

DAS

Dual Attachment Station (FDDI)

DASS

Digital Access Signalling System

DASD DAT

DATV DAU dB

dBa

Direct Access Storage Device

Digital Audio Tape

Digitally Assisted TV

Data Adapter Unit

Decibel

Decibels Adjusted

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34

DBMS

Acronyms and Abbreviations in Telecommunications

Database Management System

DBS

Direct Broadcasting by Satellite

DC

Direct Current

DBS

Database System

DC

Dry Circuit

DCC

Data Communications Channel

DCA DCCH DCD

Data Communications Agreement Dedicated Control Channel

Data Carrier Detect

DCE

Data Circuit-Terminating Equipment

DCE

Distributed Computing Environment

DCE DCF DCF

Data Communications Equipment

Data Communications Function Block (TMN) Data Count Field

DCL

Direct Communications Link

DCN

Data Communications Network

DCME DCOM

DCOSS

Digital Circuit Multiplication Equipment

Distributed Component Object Model

Digital Central Office Switch Simulator

DCP

Digital Communications Protocol

DCPSK

Differentially Coherent Phase-Shift Keying

DCPN

Domestic Customer Premises Network

DCS

Digital Cellular System

DCS

Digital Crossconnect System

DCS DCS1800

Digital Communication Systems Digital Communications System 1800 MHz

Acronyms and Abbreviations in Telecommunications

DCT

DCU

Discrete Cosine Transform

Digital Concentrator Unit

DCU

Distribution and Control Unit

DDBS

Distributed Data Base System

DCWV DDD

Direct-Current Working Volts Direct Distance Dialling

DDE

Dynamic Data Exchange

DDI

Direct Dialling In

DDF

DDM DDM

Digital Distribution Frame Digital Data Multiplexer

Distributed Data Management

DDN

Defense Data Network (US)

DDR

Double Data Rate

DDS

Digital Data Service

DE

Discard Eligible

DEK

Data Encryption Key

DDR DDS DDS

DECT DEL

DELTA DEM

demarc demux DEN

Dial-on-Demand Routing

Dataphone Digital Service

Direct Digital Synthesis

Digital Enhanced Cordless Telecommunications

Direct Exchange Line

Developing European Learning through Technological Advance Digital Elevation Model

Demarcation Point

Demultiplexer

Document Enabled Networking

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36

Acronyms and Abbreviations in Telecommunications

dequeue

Double-Ended Queue

DES

Direct Extension Select

DES DES

Data Encryption Standard

Destination End Station

detem

Detector/Emitter

DFC

Data Flow Control

DF

DFS

DFSK

Directional Finding Distributed File System

Double-Frequency Shift Keying

DG

Directorate General (European Commission)

DHCP

Dynamic Host Configuration Protocol

DIA

Document Interchange Architecture

DIEL

Advisory Committee on Telecommunications for Disabled and Elderly People (UK)

DGPS

DHTML DID

DILIC DIN DIP

Differential Global Positioning System

Dynamic Hypertext Mark-up Language

Direct Inward Dialling

Dual Inline Integrated Circuit

Deutsches Institut für Normung (German Standards Institute) Dual In Line Package (integrated circuits)

DIS

Draft International Standard

DISN

Defence Information System Network

DISA

DISNET DJSU DKT

Direct Inward System Access

Defence Integrated Secure Network

Digital Junction Switching Unit Digital Key Telephone

Acronyms and Abbreviations in Telecommunications

DL

DLC

Dial Level

Digital Loop Carrier

DLCI

Data-Link Connection Identifier

DLE

Digital Local Exchange

DLCS DLG DLL

Digital Loop Carrier System

Digital Line Graph

Dynamic Link Library

DLSw

Data Link Switching

DLU

Digital Line Unit

DM

Disconnected Mode (HDLC)

DLTE DM DM

DMA DMA DMB

DMC DME DME DMI

Digital Local Tandem Exchange Delta Modulation

Distributed Management Direct Memory Access

Data Management Amendment

Dynamic Multipoint Bridging

Desktop Multimedia Conferencing Distance Measuring Equipment

Distributed Management Environment

Distributed Management Interface

DMOQ

Direct Measures of Quality

DMS

Digital Multiplex Switch

DMS DMS

DMSU DMT

Defence Message System

Digital Multiplexer System

Digital Main Switching Unit Discrete Multitone

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38

DMTF DNA

DNIC DNIS

DNPA DNS

DNSIX DNU

Acronyms and Abbreviations in Telecommunications

Desktop Management Task Force

Digital Network Architecture

Data Network Identification Code (X121) Dialled Number Identification Service Data Numbering Plan Area

Domain Name Service

Department of Defense Intelligence Information System Network Security for Information Exchange (US) Digital Networking Unit

DO

Design Objective

DOD

Direct Outward Dialling

DOSE

Direction of Arrival by Signal Elimination

DOVE

Data Over Voice Equipment

DOCSIS DoS

DOV DP

Data Over Cable Services Interface Specifications Denial of Service

Data Over Voice Dial Pulsing

DP

Dialling Plan

DPCM

Differential Pulse Code Modulator

DP

Distribution Point

DPE

Data Processing Equipment

DPNSS

Digital Private Network Signalling System

DPIT

DPSK DQ

DQDB

DQPSK

Designated Profile Interoperability Testers Differential Phase-Shift Keying

Directory Enquiries Service

Distributed Queue Dual Bus

Differential Quadrature Phase Shifting Key

Acronyms and Abbreviations in Telecommunications

DR

Distortion Ratio

DRNC

Drift Radio Network Controller

DRX

Discontinuous Reception

DS

Digital Signal

DS

Direct Support

DRAM DRSI DS DS DS DS

DSA DSA

Dynamic Random-Access Memory

Destination Station Routing Indicator Data Set

Direct Sequence Dual Signalling (Loop-Disconnect and DTMF)

Duplex Signalling

Dial Service Assistance Data Service Unit

DSA

Directory Service Agent

DSAP

Destination Service Access Point

DSA DSB

Distributed Systems Architecture Double-Sideband

DSB-RC

Double-Sideband Reduced Carrier Transmission

DSC

Digital Selective Calling

DSCS

Defense Satellite Communications System (US)

DSB-SC

DS-CDMA

Double-Sideband Suppressed-Carrier Transmission Direct-Sequence Code Division Multiple Access

DSE

Data Switching Equipment

DSI

Detailed Spectrum Investigation of Radio uUsage (as conducted by CEPT/ERO)

DSG

Data Systems Group

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40

Acronyms and Abbreviations in Telecommunications

DSI

Digital Speech Interpolation

DSLAM

Digital Subscriber Line Access Multiplexer

DSL

DSMA

Digital Subscriber Line

Digital Sense Multiple Access

DSN

Derived Services Network

DSR

Data Signalling Rate

DSS

Dial Selective Signalling

DSS

Digital Subscriber Signalling System (ISDN B-ISDN)

DSP

DSRR DSS DSS DSS DSS

DSSCS DSTE DSU DSU

DSVD DT DT

DTAM DTAP

Digital Signal Processor

Digital Short Range Radio

Decision Support System

Digital Switched Services

Direct Sequence Spread Spectrum Direct Station Selection

Defence Special Service Communications System

Data Subscriber Terminal Equipment

Data Service Unit

Digital Service Units

Digital Simultaneous Voice and Data

Data Terminal

Dial Tone

Document Transfer and Manipulation (ISO)

Direct Transfer Application Part

DTE

Data Terminal Equipment

DTH

Direct-to-Home

DTG

Date-Time Group

Acronyms and Abbreviations in Telecommunications

DTLU

Digital Terminal Line Unit

DTMF

Dual Tone Multi Frequency

DTM

Digital Terrain Model

DTN

Data Transmission Network

DTS

Digital Transmission System

DTP

Detail Test Plan

DTU

Data Transfer Unit

DTU

Direct to User

DTU DTV

DTX

Data Tape Unit

Digital Television

Discontinuous Transmission

DUA

Directory User Agent

DVL

Direct Voice Link

DVB

DVM

DVMRP

Digital Video Broadcasting Data over Voice Multiplexer

Distance Vector Multicast Routing Protocol

DVRA

Distance Vector Routing Algorithm

DWDM

Dense Wavelength Division Multiplexing

DXC

Digital Cross Contact

DVT

DWMT DXI

Digital Video Terminal

Discreet Wavelet Multi-Tone

Data Exchange Interface (ATM SMDS)

41

E

42

Acronyms and Abbreviations in Telecommunications

E&M

Ear and Mouth (handset)

E&M

Receive and Transmit (signalling)

E&M

Earth and Magnet

E/O

Electro-Optical Conversion

EA

Evaluation Authority

E2E EACEM EAI

End-to-End

European Association of Consumer Electronics Manufacturers

Emergency Access Interface

EAI

Enterprise Application Integration

EBC

Element-Based Charging

EBITDA

Earnings before Income Tax, Depreciation and Amortisation

EAS EBIT EBO

E-Bone EBS

EBU EBX EC EC

ECBF ECC

Extended Area Service

European Broadband Interconnection Trial

Embedded Base Organisation

European Backbone (Pan-European Network Backbone Service) Emergency Broadcast System

European Broadcasting Union Electronic Branch Exchange Earth Coverage

Earth Curvature

European Citizen’s Band Federation

Electronically Controlled Coupling

Acronyms and Abbreviations in Telecommunications

ECC

Enhanced Call Completion

ECCM

Electronic Counter-Countermeasures

ECCA ECET

ECFRN ECHO

European Cable Communication Association European Country in Economic Transition

European Consultative Forum for Research Networking

European Commission Host Organisation

ECI

European Cooperation in Informatics

ECITC

European Committee for IT Testing and Certification

ECIP ECM

ECMA ECP

European Cooperation in Information Processing Electronic Countermeasures

European Computer Manufacturers’ Association

European Common Proposal

ECS

European Communications Satellite

ECSA

Exchange Carriers’ Standards Association (now ATIS)

ECSA ECTA

ECTEL ECTEL ECTF

ECTRA ECTS

ECTUA EDC

European Computing Software Association European Competitive Telecommunications Association

European Conference of Telecommunications and Electronics Industries

National Telecommunications Regulatory Commission (Grenada) Enterprise Computer Telephony Forum

European Committee for Telecommunications Regulatory Affairs Electronic Custom Telephone System

European Council of Telecommunications Users’ Association

Error Detection and Correction

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44

Acronyms and Abbreviations in Telecommunications

EDGE

Enhanced Data-Rates for GSM Evolution

EDI

Electronic Data Interchange

EDH

EDIFACT EDM

EDNS

Electronic Document Handling

Electronic Data Interchange for Administration Commerce and Trade (ANSI) Electronic Distance Measurement

Enterprise Defined Network Services

EDP

Electronic Data Processing

EECM

End-to-End Call Manager

EDTV

EEHO

EEMA

EEPROM

Extended-Definition Television

Either End Hop Off

European Electronic Mail Association

Electrically Erasable Programmable Read-Only Memory

EEROM

Electronically Erasable Read-Only Memory

EETT

National Committee of Communications & Posts (Greece)

EESS EF&I

Earth Exploration-Satellite Service

Engineering, Furnishing and Installation

EFCI

Explicit Forward Congestion Indication

EFR

Enhanced Full Rate

EFF

EFS

EFT

Electronic Frontier Foundation

End of Frame Sequence (LAN) Electronic Funds Transfer

EFTA

European Free Trade Association

EGP

Exterior Gateway Protocol

EFTPOS EGSM

Electronic Funds Transfer at Point of Sale

Extended Global System for Mobile Communications

Acronyms and Abbreviations in Telecommunications

EH

Electronic Highways

EI

Engineering Instruction

EHF EI

EIA

Extremely High Frequency

Expansion Interface

Electronics Industry Association

EIB

European Investment Bank

EIR

Equipment Identity Register

EICTA EIRP EIS

EISA

European Information Communications Technology Industry Association Effective or Equivalent Isotropically Radiated Power

Emergency Information System

Extended Industry Standard Architecture

EIUF

European ISDN User Forum

EL

Elevation

ELB

Emergency Location Beacon

ELECTROOPTINT

Electro-Optical Intelligence

ELINT

Electronics/Electromagnetic Intelligence

ELR

Earth Leg Recall

EKTS ELAN EL-display ELF

ELMI

Electronic Key Telephone Sets

Emulated LAN

Electro-Luminescent Display

Extremely Low Frequency

Enhanced Local Management Interface

ELSEC

Electronics Security

EMA

Electronic Messaging Association

ELT

Emergency Locator Transmitter

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46

Acronyms and Abbreviations in Telecommunications

EMA

Enterprise Management Architecture

EMC

Electromagnetic Compatibility

EMAG

ETSI MIS Advisory Group

EMCON

Emission Control

EME

Electromagnetic Environment

EMD EMI

EML/EMS EMP

Equilibrium Mode Distribution

Electromagnetic Interference

Element Management Layer/ Element Management Service Electromagnetic Pulse

EMR

Electromagnetic Radiation

EMS

Electronic Message System

EMRP EMS EMS

EMSEC EMU EMV

EMW EMW

Equivalent Monopole Radiated Power

Enhanced Messaging Services

Expanded Memory Specification

Emanations Security

Electromagnetic Unit

Electromagnetic Vulnerability

Electromagnetic Warfare

Electromagnetic Wave

EN

Norme Européenne (European Standard)

ENFIA

Exchange Network Facilities For Interstate Access (US)

ENO

European Numbering Office

ENF

ENG/OB ENS

European Numbering Forum

Electronic News Gathering/Outside Broadcast Enhanced Network Services

Acronyms and Abbreviations in Telecommunications

ENS

Enterprise Network Services

ENSO

ETSI National Standardisation Organisations (ETSI)

EO

End Office

EOC

Embedded Operation Channel

EOF

End of File

ENV EO

EOD EOL

EOM EOP EOP EOS

European Pre-standard

Executive Order End of Data

End of Line

End of Message

End of Program

End Output

End of Selection

EOT

End of Tape

EOTC

European Organisation for Testing and Certification

EOT

EOW EPD EPI

End of Transmission

Engineering Orderwire Early Packet Discard

External Provisioning Interface

EPIRB

Emergency Position Indicating Radio Beacons

EPOST

Electronic Point of Sale Terminal

EPMU

EPROM

Equal Proportionate Mark-Up

Erasable Programmable Read-Only Memory

EPS

End of Frame Sequence (LAN)

ER

Earth Recall

EPSCS

Enhanced Private Switched Communications System

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48

Acronyms and Abbreviations in Telecommunications

ER

Explicit Rate

ERC

European Radiocommunications Committee

ERG

European Regulators’ Group

ERLINK

Emergency Response Link

ER

ERDF ERL

ERMES ERO ERP ERP ES

Essential Requirement

European Regional Development Fund

Echo Return Loss

European Radio Message System (standard for pagers)

European Radiocommunications Office Effective Radiated Power

Enterprise Resource Planning

End System

ES

Expert System

ESAC

Emergency Switch Assistance Centre

ESC

Enhanced Satellite Capability

ESCON

Enterprise System Connection (IBM)

ESA ESB

ESC

ESD ESD

European Space Agency

European Standardisation Board

European Standardisation Council Electrostatic Discharge

European Standards Database

ESDI

Enhanced Small Device Interface

ESF

Extended SuperFrame

ESF ESI

ESIG

European Science Foundation

End System Identifier (ATM ISO)

European SMDS Interest Group

Acronyms and Abbreviations in Telecommunications

ESM

Electronic Warfare Support Measures

ESMTP

Extended Simple Mail Transfer Protocol

ESMR ESN

Enhanced Specialised Mobile Radio

Equipment Serial Number

ESO

European Standardisation Organisation

ESP

Encapsulating Security Payload (IPSec security protocol)

ESP ESP ESP

ESPRIT ESRP ESS ESS

ETACS

EBIT Service Project

Enhanced Service Provider

Extended Services Processor

European Strategic Programme for Research and Development

Ente Regulador de los Servicios Públicos (Panama)

Electronic Switching System

European Standardisation System

Extended Total Access System

ETCI

Electro-Technical Council of Ireland

E-TDMA

Enhanced TDMA

ETD

ETN

ETNO ETO ETP

Extension Trunk Dialling

Electronic Tandem Network

Association of European Public Telecommunications Network Operators European Telecommunications Office

European Telecommunications Platform

ETR

ETSI Technical Report

ETS

European Telecommunications Standard

ETS

ETSA

Emergency Telecommunications Services European Telecommunication Services Association

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50

Acronyms and Abbreviations in Telecommunications

ETSI

European Telecommunications Standard Institute

EUREKA

European Research Co-operation Agency

EURESCOM

European Institute for Research and Strategic Studies in Telecommunications

EUMETSAT EUREKA-95 EUROBIT EurOSINET EUSIDIC

EUTELSAT EV

European Meteorological Satellite Organisation

European Research Project on HDTV

European Association of Manufacturers of Business Machines and Data Processing Equipment European OSI Network

European Association of Information Services

European Telecommunications Satellite Organisation

European Videocommunications

EW

Electronic Warfare

EWP

ETSI Work Programme

EWOS EXCSA EXZ

European Workshop for Open Systems

Exchange Carriers Standards Association

Excessive Zeros

F

Acronyms and Abbreviations in Telecommunications

F

Frequency

FAC

Fully Allocated Costs

FAN

Flexible Access Network

FAA FACCH FAQ FAS FB

Federal Aviation Administration (US)

Fast Association Control Channel

Frequently Asked Questions

Frame Alignment Sequence (T-1 and E1)

Framing Bit

FC

Fibre Channel

FC

Functional Component

FCC

Federal Communications Commission (USA)

FCS

Federation of Communications Services (UK)

FC FCAPS FCCH FCS FD

Frame Control

Fault, Configuration, Accounts, Performance, Security (ISO) Forward Control Channel Frame Check Sequence Full Duplex

FDC

Fully-Distributed Costs

FDDI

Fibre Distributed Data Interface

FDM

Frequency Division Multiplexing

FDMMA

Frequency Division Multiplexing Multiple Access

FDD

FDHM FDMA

Frequency Division Duplex

Full Duration at Half Maximum

Frequency Division Multiple Access

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52

FDP

FDX FEC

FECN

FED-STD

Acronyms and Abbreviations in Telecommunications

Floor Distribution Point

Full Duplex

Forward Error Correction

Forward Explicit Congestion Notification Federal Standard (US)

FEI

Federation of the Electronics Industry (UK)

FEP

Front-End Processor

FEMA FET

FEXT FFSK FFT FG

FH

FH/DS FHSS FIAG FIB

FICORA FIFO FIPS

Federal Emergency Management Agency (US)

Field Effect Transistor Far End Cross Talk Fast FSK

Fast Fourier Transform

Feature Group

Frequency-Hopping

Frequency-Hopping Direct Sequence

Frequency-Hopping Spread Sequence

Framework Interconnection Agreement Guidelines

Focused Ion Beam

Finnish Communications Regulatory Authority First In/First Out

Federal Information Processing Standards

FIR

Finite Impulse Response

FITL

Fibre In The Loop

FLS

Fallback/Fall-Forward Line Sensing

FIRMR FLOPS

Federal Information Resources Management Regulations

Floating-Point Operations Per Second

Acronyms and Abbreviations in Telecommunications

FLT

Full Line Terminal Multiplexer

FM

Function Management

FM

Frequency Modulation

FMC

Fixed Mobile Convergence

FMS

Fraud Management System

FMH FNC FO

FOC

Function Management Header (SNA)

Federal Networking Council (US)

Fibre Optic

Final Operational Capability

FOC

Full Operational Capability

FoIP

Fax over Internet Protocol

FOD FOIRL FOT

FOTP

Fax on Demand

Fibre Optic Interrepeater Link

Frequency of Optimum Transmission

Fibre Optic Transmittance Procedure

FOTS

Fibre Optics Transmission Systems

FPIS

Forward Propagation Ionospheric Scatter

FR

Frame Relay

FPD

FPLMTS

Flat Panel Display

Future Public Land Mobile Telecommunication System

FR

Frequency Response

FRAD

Frame Relay Access Device

FRBS

Frame Relay Bearer Service

FRAD FRASM FRF

Frame Relay Assembler/ Disassembler Frame Relay Access Service Module

Frame Relay Forum

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54

Acronyms and Abbreviations in Telecommunications

FRIACO

Flat Rate Internet Access Call Origination

FRS

Frame Relay Service

FRM FRS

FSAN

FSDPSK FSK

Functional Reference Model

Frame Relay Switch

Full Service Access Network

Filtered Symmetric Differential Phase-Shift Keying

Frequency Shifting Sequence

FSL

Flexible Service Logic

FT

Fibre Optic T-Carrier

FTAM

File Transfer Access & Management

FSS

FT1

FTF

FTP

FTPF FTS

FTSC

FTTB

FTTC

Fixed-Satellite Service

Fractional T1

Federal Telecommunications Fund (US) File Transfer Protocol

File Transfer Protocol Filter

Federal Telecommunications System (US)

Federal Telecommunications Standards Committee (US)

Fibre to the Building

Fibre to the Curb (North America)

FTTCab

Fibre to the Cabinet

FTTH

Fibre to the Home

FTTEx FTTK

FTTN FUNI FVC

Fibre to the Exchange Fibre to the Kerb (UK)

Fibre to the Neighbourhood

Frame User-to-Network Interface (ATM) Forward Voice Channel

Acronyms and Abbreviations in Telecommunications

FWA

Fixed Wireless Access

FWM

Four Wave Mixing

FWHM

Full Width At Half Maximum

FX

Fixed Service

FXO

Foreign Exchange Office

FX

FXS

Foreign Exchange Service Foreign Exchange Station

55

G

56

Acronyms and Abbreviations in Telecommunications

G.lite

G.992.2 Standard for Asymmetric DSL Technology

GA

General Assembly (ETSI)

G/T

Antenna Gain-to-Noise-Temperature

GAC

Governmental Advisory Committee (ICANN)

GAP

Generic Access Profiles

GAN GASP

GATT GBH

GCAC GCC

Global Area Network

Gatekeeper Synchronisation Protocol

Global Agreement on Tariffs and Trade

Group Busy Hour

Generic Connection Admission Control

Generic Conference Control

GCCC

Global Customer Care Center

GDF

Group Distribution Frame

GCRA GDS

Generic Call Rate Algorithm Generic Digital Services

GEA

Gigabit Ethernet Alliance

GEO

Geostationary Earth Orbit

GFC

Generic Flow Control (ATM)

GGCL

Government-to-Government Communications Link

GGSN

Gateway GPRS Support Node

GEN

GETS GFI

GGP

Global European Network Government Emergency Telecommunications Service

Genera Format Identifier (X25) Gateway-to-Gateway Protocol

Acronyms and Abbreviations in Telecommunications

GIBN

Global Interoperability of Broadband Networks

GIO

General Interest Obligations

GII

GIO GIS

Global Information Infrastructure

Generic Interface for Operations (SMDS) Geographical Information System

GIX

Global Internet eXchange

GMDSS

Global Maritime Distress and Safety System

GLONASS

Global Navigation Satellite System

GMPCS

Global Mobile Personal Communication by Satellite

GMSC

Gateway Mobile Services Switching Centre

GNCC

Georgian National Communications Commission

GMRS

GMSK GNOC GNS

General Mobile Radio Service

Gaussian Minimum Shifting Keying

Global Network Operation Centre Get Nearest Server

GOF

Glass Optical Fibre

GOSIP

Government Open Systems Interconnection Profile

GoS

GPIB

GPRS GPS GR

GRE

GRX GS

GSA

Grade of Service

General Purpose Interface Bus General Packet Radio Service

Global Positioning System

GPRS Register

Generic Routing Encapsulation GPRS Roaming Exchange Ground-Start Signalling

General Services Administration (US)

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58

Acronyms and Abbreviations in Telecommunications

GSA

Global Mobile Suppliers Association

GSLB

Groupe Spécial Large Bande (CEPT group on broadband telecommunications)

GSA

GSM GSM MS

GSM PLMN GSM900 GSMP

GSM-R GSN

GSM System Area

Global System for Mobile (second-geration mobile telephony standard) GSM Mobile Station

GSM Public Land Mobile Network

Global System for Mobile 900 MHz

Global Service Management Platform

GSM for Railways

GPRS Support Node

GSO

Geostationary Orbit

GSS

Group Switching Subsystem

GTD

Geometric Theory of Diffraction

GSS

GSTN GTP GTP

Generic Service State

General Switched Telephone Network Government Telecommunications Programme

GPRS Tunnelling Protocol

GTR

General Technical Requirements (Russia)

GVPN

Global Virtual Private Network

GTS

Government Telecommunications System

H

Acronyms and Abbreviations in Telecommunications

H Channel

High-Speed Channel (ISDN)

HARCENELEC

Agreement for Electrical Cords and Cables

HBS

Home Base Station

HACMP HBN

HCA

HCDS HCM

High-Availability Cluster Multiprocessing

High Bandwidth Networking Historic Cost Accounting

High-Capacity Digital Services

High Capacity Multiplexing

HCS

Hard Clad Silica [fibre]

HCV

High Capacity Voice

HCSPR HD

Hundred Call Seconds Per Hour

Half Duplex

HD

Harmonic Distortion

HDF

Hand-Over Distribution Facility

HDDV HDLC

HDML HDSL

High Definition Digital Video

High-Level Data Link Control

Handheld Device Markup Language

High-Data-Rate Digital Subscriber Line

HDT

Host Digital Terminal

HDTV

High Definition Television

HDTM HDWDM HDX HEC

Half-Duplex Transmission Module (X25)

High Density Wavelength Division Multiplex

Half-Duplex

Header Error Control

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60

Acronyms and Abbreviations in Telecommunications

HEHO

Head End Hop Off

HEPnet

High-Energy Physics Network

HEMP HERF

HERO HERP HES HF

High-Altitude Electromagnetic Pulse

Hazards of Electromagnetic Radiation to Fuel

Hazards of Electromagnetic Radiation to Ordnance Hazards of Electromagnetic Radiation to Personnel

Home Electronic System(s)

High Frequency

HFC

Hybrid Fibre/Coax

HIC

Head-End Interface Converter

HFDF HiCap

HIPERLAN HIPPI HIS

HLC

High-Frequency Distribution Frame

High-Capacity Digital Services

High Performance Local Area Network

High Performance Parallel Interface

Hospital Information System

High Layer Compatibility (ISDN)

HLC

High Level Committee (ITU)

HLR

Home Location Register

HLL

HNPA

HOSTID HP/PN

High Level Language

Home Numbering Plan Area Host Identifier

Hybrid Private/Public Networking

HPC

High Probability of Completion

HPPI

High-Performance Parallel Interface

HPLMN HPR

Home Public Land Mobile Network

High Performance Routing

Acronyms and Abbreviations in Telecommunications

HS

High Speed

HSC

Hierarchical Cell Structure

HSCSD

High Speed Circuit Switched Data

HSCSD

High Speed Circuit Switched Data

HSLAN

High Speed LAN

HSSI

High-Speed Serial Interface (ANSI)

HSPSD HTML HTTP HV

HW

High-Speed Packet Switched Data

Hypertext Markup Language

Hypertext Transfer Protocol (IETF)

High Voltage

Hardware

61

I

62

I&A I&C

I&M I/F

I/O IA

Acronyms and Abbreviations in Telecommunications

Identification and Authentication

Installation and Checkout

Installation and Maintenance

Interface

Input/Output

International Alphabet [CCITT]

IAB

Internet Architecture Board

IACS

Integrated Access and Crossconnect System

IAC

IAFIS

Install and Commission

Integrated Automated Fingerprint Identification System

IAHC

Internet International Ad Hoc Committee

IANA

Internet Address Naming Authority

IBC

Integrated Broadband Communication

IBN

Integrated Broadband Network

IAM

IARU IBCN IBS IC

Initial Address Message (SS7)

International Amateur Radio Union

Integrated Broadband Communications Network International Business Service (INTELSAT)

Incoming

IC

Integrated Circuit

ICANN

Internet Corporation for Assigned Names and Numbers

IC

ICASA ICCB

Interconnect

Independent Communications Authority of South Africa

Internet Control and Configuration Board

Acronyms and Abbreviations in Telecommunications

ICD ICD

ICGB ICI ICI

Internal Cable Distribution

International Code Designator (ISO)

Institut des Communications de la Guinée-Bissau Incoming Call Identification

Intercarrier Interface (SMDS)

ICI

Interexchange Carrier Interface (US)

ICNI

Integrated Communications, Navigation, and Identification

ICMP ICP

Internet Control Message Protocol

Internet Control Protocol

ICR

Initial Cell Rate

ICS

Implementation Conformance Statement

ICR ICS

ICSA

Intelligent Call Routing

Intelligent Calling System ID Identification

International Computer Security Association

ICT

Information and Communication Technologies

ICW

Interrupted Continuous Wave

IDA

Infocomm Development Authority of Singapore

ICTA ID

IDA

Information and Communication Technologies Authority (Mauritius) Identification

Integrated Data Access

IDC

Insulation Displacement Connection

IDDD

International Direct Distance Dialling

IDD

IDDD iDEN

International Direct Dialling

International Direct Dialling Designator Integrated Dispatch Enhanced Network

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64

IDF IDI

Acronyms and Abbreviations in Telecommunications

Intermediate Distribution Frame

Initial Domain Identifier (ISO)

IDLC

Integrated Digital Loop Carrier (Telephony)

IDNX

Integrated Digital Network Exchange

IDN IDP

Integrated Digital Network Initial Domain Part

IDP

Internet Datagram Protocol

IDR

Intermediate Data Rate/Intelsat Digital Route

IDPR IDS

IDTV IE

Inter-Domain Policy Routing

Intrusion Detection System

Improved-Definition Television

Information Element

IEC

Interconnection Extension Circuit

IEC

International Electrotechnical Commission

IEEE

Institute of Electrical and Electronic Engineers (UK)

IEC IEE

IEPG IES

Interexchange Carrier

Institution of Electrical Engineers (UK) Internet Engineering Planning Group

Industry Executive Subcommittee

IES

Information Exchange Services

IETF

Internet Engineering Task Force

IESG IETF

I-ETS IF

IFFT

Internet Engineering Steering Group Internet Engineering Task Force

Interim European Telecommunications Standard

Intermediate Frequency Inverse FFT

Acronyms and Abbreviations in Telecommunications

IFIP IFL

IFRB IFS

IGMP

International Federation for Information Processing

International Frequency List

International Frequency Registration Board (now Radio Regulations Board ) Ionospheric Forward Scatter

Internet Group Management Protocol

IGP

Internet Gateway Protocol

IHL

Internet Header Length (IP)

IIR

Infinite Impulse Response

IITF

Information Infrastructure Task Force

IGRP IHS IIT

IKE

ILD

Interior Gateway Routing Protocol In-House System

Integrated Information Transport Internet Key Exchange

International Long Distance

ILEC

Incumbent Local Exchange Carrier (US)

IM

Instant Messaging

ILR IM IM

Institut Luxembourgeois de Régulation Intensity Modulation Intermodulation

IMA

Invere Multiplexing over ATM

IMCC

ISDN Management and Co-ordinating Committee

IME

International Mobile Station Equipment Identity

IMAP IMD

IMEI

Internet Message Access Protocol

Intermodulation Distortion

International Mobile Equipment Identity

65

66

IMN

Acronyms and Abbreviations in Telecommunications

Intelligent Mobile Network

IMO

International Maritime Organisation

IMP

Intermodulation Products

IMP IMS

Interface Message Processor

Internet Management System

IMSI

International Mobile Station Identity

IMT

International Mobile Telecommunications

IMSI

International Mobile Subscriber Identity

IMTC

International Multimedia Conferencing Consortium

IMUX

Intelligent Multiplexer

IN

Intelligent Network (AIN)

INACOM

Institut Angolais des Communications (Angola)

IMTS

IMUX INA

INAP

Improved Mobile Telephone Service

Inverse Multiplexer

Information Networking Architecture Intelligent Network Application Part

INCA

Inter Network Call Accounting system

INE

Intelligent Network Element

INLSP

Integrated Net Layer Security Protocol

INCM INFOSEC INMARSAT INMS INS

INTAP

Instituto Nacional das Comunicações de Moçambique (Mozambique)

Information Systems Security

International Marine Satellite Organisation

Integrated Network Management System

Inertial Navigation System

Interoperability Technology Association for Information Processing

Acronyms and Abbreviations in Telecommunications

INTELSAT INTT

INTUG

INWATS IO

International Satellite Organisation

Instance Nationale des Télécommunications (Tunisia)

International Telecommunications User Group Inward Wide-Area Telephone Service

Input/Output

IOC

Integrated Optical Circuit

IOC

Initial Operational Capability

IOC

Inter Office Channel

IOC IOC

Independent Operating Company (US)

Input-Output Controller

IOCC

I/O Channel Controller

IONL

Internal Organisation of the Network Layer

ION

IOPS IOT IP IP

Integrated Optical Network

Internet Operators’ Providers Services

Inter-Office Trunk

Intellectual Property

Intelligent Peripheral

IP

Interexchange Plant

IPA

Intermediate Power Amplifier

IP

Internet Protocol

IPC

Information Processing Center

IPCP

Internet Protocol Control Protocol

IPC

IPM IPM IPM

Interprocess Communication Impulses Per Minute

Interference Prediction Model

Internal Polarisation Modulation

67

68

IPM

Acronyms and Abbreviations in Telecommunications

Interruptions Per Minute

IPN

Intelligent Peripheral Node

IPoATM

Internet Protocol over ATM

IPNS

ISDN PBX Networking Specification

IPR

Intellectual Property Rights

ips

Interruptions Per Second

IPSO

IP Security Option

IPS

IPSec IPT

IPv6 IPX IQF IR IR

Instructions Per Second

Internet Protocol Security Internet Protocol Telephony Internet Protocol Version 6

Internetwork Packet Exchange (NetWare)

Intrinsic Quality Factor Infrared

Internet Registry

IRAC

Interdepartment Radio Advisory Committee

IRB

Integrated Routing and Bridging

IRAS

Internet Routing and Access Service

IRC

International Record Carrier

IrDA

Infrared Data Association

IRC

IRG

Internet Relay Chat

Independent Regulators’ Group (Europe)

IrLAN

Infrared LAN

IRN

Intermediate Routing Node

IrLAP IRP

Infrared Link Access Protocol Independent Routing Processor

Acronyms and Abbreviations in Telecommunications

IRPA

International Radiation Protection Association

IRQ

Interrupt Request

IRSG

Internet Research Steering Group

IRR IRT

IRTA IRTF

Internal Rate of Return (Financial Modelling) Integrated Rural Telematics

Integrated Regional Telematics Architecture Internet Research Task Force

IS

In-Service

IS

Interim Standard (ISO)

IS

Information Systems

IS

Intermediate System (ISO)

ISAC

Information Society Activity Centre (European Commission)

ISA ISB

Industry Standard Architecture

Independent Side Band

ISC

International Switching Centre

ISDN

Integrated Services Digital Network

ISD ISE

International Subscriber Dialling (now IDD)

Integrated Service Engineering

ISI

In Span Interconnection

ISL

Inter-Switch Link

IS-IS ISM ISM ISM ISN

Intermediate System-to-Intermediate System

Industrial, Scientific, and Medical (applications and frequency bands) Internetwork Status Monitor

ISDN Standards Management

Information Systems Network

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70

ISO

Acronyms and Abbreviations in Telecommunications

International Organisation for Standardisation

ISOC

Internet Society

IS-PBX

Integrated Services Private Branch Exchange

ISP

ISPO ISR

Internet Service Provider

Information Society Promotion Office (European Commission) International Simple Resale

ISSI

Inter-Switching System Interface

ISV

Independent Software Vendor

ISUP ISVR

ISDN User Part

International Simple Voice Resale

IT

Information Technology

IT&T

Information Technologies & Telecommunications

IT

ITA

Information Type

International Telegraph Alphabet

ITC

International Teletraffic Congress

ITN

Independent Telecommunication Network

ITS

Insertion Test Signal

ITM ITR ITS

Isochronous Transmission

Intelligent Text Retrieval

Institute for Telecommunication Sciences

ITSC

Interregional Telecommunications Standards Conference

ITSP

Internet Service Telephony Provider

ITSO ITST

ITSTC

International Telecommunications Satellite Organisation National IT and Telecom Agency (Denmark)

Information Technology Steering Committee

Acronyms and Abbreviations in Telecommunications

ITT&B ITU

ITU-R ITU-T ITUSA

Information Technologies Telecommunications & Broadcasting International Telecommunications Union

International Telecommunication UnionRadiocommunications

International Telecommunication UnionTelecommunications

Information Technology Users Standards Association

IUC

Interconnection Usage Charge

IVDS

Interactive Video Data Services

IVN

Intervening Network (ETSI)

IVR

Interactive Voice Response

IWF

Inter-Working Function

IVDM IVDT IVPN IVS

IWU

Integrated Voice Data Multiplexer

Integrated Voice and Data Terminal

International Virtual Private Networks

Interactive Video Service

Inter-Working Unit (ETSI TC BT)

IXC

Inter-Exchange Mileage

IXIT

Implementation Extra Information for Testing

IXC

Inter-Exchange Carrier (US)

71

J

72

JADSL

JANET

Acronyms and Abbreviations in Telecommunications

ADSL for ISDN

Joint Academic Network (UK)

JCCR

Joint Committee on Cellular Roaming

JDBC

Java Database Connectivity

JEEC

Joint ECMA ETSI Programme Committee

JPEG

Joint Photographic Experts Group (ISO)

JCG JDC JIT

JRTIC JSC

JTACS

Joint Co-ordination Group (CEN/CENELEC/ETSI) Japan’s Digital Cellular Just In Time

Joint Radiophone Technical Interfaces Group Joint Spectrum Centre (US) Japanese TACS System

JTC

Joint Technical Committee (EBU/ETSI and ISO/IEC)

JTM

Job Transfer and Management

JTCG JUNET

Joint Technical Co-ordination Group Japan UNIX Network Nationwide

K

Acronyms and Abbreviations in Telecommunications

K/D KA

Keyboard/Display

Keep Alive Signal

Kbps

Kilo bits per second

KCC

Korea Communications Commission

KDR

Keyboard Data Recorder

KBS

KDC KDS kHz

KMC KS

KSR

KSU

Knowledge-Based System

Key Distribution Centre

Key Distribution Service

Kilohertz

Key Management Centre

Kearny Specification (US)

Keyboard Send/Receive Device

Key Service Unit

kT

Noise Power Density

KTU

Key Telephone Unit

KTS

Key Telephone System

73

L

74

l/m L1

Acronyms and Abbreviations in Telecommunications

Lines per Minute

Layer 1 (physical layer)

L2

Layer 2 (data link layer)

LADS

Local Area Data Service

L3

Layer 3 (network layer)

LAI

Location Area Identification or Identity

LAN

Local Area Network

LANS

Local Area Network Services

LAMs LANE LAP

Line Adaptor Modules

LAN emulation

Link Access Procedure (X25)

LAP-B

Link Access Protocol-Balanced

LAPF

Link Access Procedure to Frame mode bearer services (FR ISDN)

LAPD

LAPM

Link Access Procedure for the D-channel (ISDN) Link Access Procedure for Modems (V42)

LAPX

Link Access Procedure Half-Duplex (X32)

LATA

Local Access and Transport Area (US)

LB

Local Battery

LBO

Line Buildout

LC

Limited Capability

LASS LATS LBA LBS

Local Area Signalling Services Loop Access Test System

Location Based Advertising Location-Based Services

Acronyms and Abbreviations in Telecommunications

LCD

Liquid Crystal Display

LCI

Logical Channel Identifier

LCN

Local Communication Network

LCM

Line Concentrator Module

LCN

Logical Channel Number (X25)

LCR

Least Cost Routing

LD

Long Distance

LCP

LCV LD LD

Link Control Protocol Line Code Violation

Loop Dial

Loop Disconnect

LDC

Long Distance Carrier

LDDI

Local Distributed Data Interface (ANSI)

LDCELP LDM LDN

Low-Delay Code Excited Linear Prediction Compression Limited Distance Modem

Listed Directory Number

LE

Local Exchange (ISDN)

LEC

LAN Emulation Client.

LE_ARP

LAN Emulation Address Resolution Protocol Protocol

LEC

Local Exchange Carrier

LEO

Low Earth Orbit

LECS LEOS LES LF

LAN Emulation Configuration Server

Low Earth Orbit Satellites LAN Emulation Server

Low Frequency

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76

Acronyms and Abbreviations in Telecommunications

LFB

Look-Ahead-For-Busy

LI

Length Indicator

LFR LIDB LIFO

LIMO LIS

Less Favoured Region

Line Information Database (ISDN)

Last In First Out Limited Mobility

Logical IP Subnet

LJU

Line Jack Unit

LLB

Line LoopBack

LLC

Logical Link Control

LL

LLC LLU

LMDS LMF

Leased Lines

Low Layer Compatibility (ISDN) Local Loop Unbundling (see also ULL) Local Multipoint Distribution System

Language Media Format

LMI

Local Management Interface

LMR

Land Mobile Radio

LMOS LMS

LMSS LMT LNA LNA

Loop Maintenance Operations System Location and Monitoring Service Land Mobile Satellite Service

Local Maintenance Terminal

Launch Numerical Aperture

Low Noise Amplifier

LNB

Low Noise Block

LNP

Local Number Portability

LNM

LAN Network Manager

Acronyms and Abbreviations in Telecommunications

LNR LO

Last Number Redial

Local Oscillator

LOB

Line Of Bearing

LORAN

Long-Range Radio Aid To Navigation System

LOF

LOS LOS LP LP

Lowest Operating Frequency Line Of Sight

Loss Of Signal

Linear Programming Linearly Polarised

LP

Linking Protection

LPA

Linear Power Amplifier

LP

Log-Periodic

LPC

Linear Predictive Coding

LPD

Low Probability Of Detection

LPD LPI

LQA

Low Power Device

Low Probability of Intercept

Link Quality Analysis

LRAIC

Long Run Average Incremental Costs

LRIC

Long Run Incremental Costs

LSB

Lower Sideband, Least Significant Bit

LSI

Line Status Indication

LRC LS

LSI

LSL

LSPSD

Longitudinal Redundancy Check Loop-Start Signalling

Large Scale Integrated or Integration Link Support Layer

Low-Speed Packet Switched Data

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78

LSRP LST LT

LTA LTC

LTE

LTU

Acronyms and Abbreviations in Telecommunications

Link-State Routing Protocol

Loudspeaking Telephone

Line Termination

Lesotho Telecommunications Authority

Line Traffic Coordinator

Line Terminating Equipment Line Termination Unit

LU

Logical Unit (IBM)

LULT

Line-Unit-Line Termination

LUF

Lowest Usable Frequency

LUNI

LAN Emulation User-to-Network Interface

LV

Low Voltage

LUNT LVD

Line-Unit-Network Termination

Low Voltage Directive (European Union)

M

Acronyms and Abbreviations in Telecommunications

M/W MA

Microwave

Medium Adaptor

MAC

Media Access Control

MAC

Move, Add, and Change

MAC MAC MAC MACRA MAE

Medium Access Control (protocol layering context) Multiplexed Analogue Components

Standards Multiplex of Analogue Components (time division multiplex technique for TV/HDTV transmission) Malawi Communications Regulatory Authority Metropolitan Access Exchange

MAE

Metropolitan Area Exchange

MAI

Mobile Allocation Index

MAN

Metropolitan Area Networks

MAP

Mobile Application Part

MAF

Malware MAP

MAP/TOP MAPI MAPS MAR

MARS

Management Application Function (TMN) Malicious Software

Manufacturing Automation Protocol

Manufacturing Automation Protocol/Technical and Office Protocol Messaging Applications Programming Interface (Microsoft) Maps Application Provisioning System

Memory Address Register

Multicast Address Resolution Server

79

80

maser MAT

MATSE

Acronyms and Abbreviations in Telecommunications

Microwave Amplification by the Stimulated Emission of Radiation Maintenance Acceptance Test

Mobile Automatic Telephone System - Europe

MAU

Maximum Attachment Unit

MAU

Medium Attachment Unit (Ethernet)

MAU MAU

MBFT

M-Bone Mbps

MBR MBS MC MC

MCA MCA MCC MCC

Medium Access Unit

Multistation Access Unit

Multipoint Binary Transfer File

Multimedia Backbone

Megabits per second

Maritime Business Radio

Mobile Broadband System

Management Centre

Message Centre

Malta Communications Authority Micro Channel Architecture

Maintenance Control Circuit

Mobile Country Code

MCCOI

Multimedia Communications Community of Interest

MCF

Message Communication Functions (TMN)

MCM

Multicarrier Modulation

MCDV MCLR

MCMC MCPC

Maximum Cell Delay Variation

Maximum Cell Loss Ratio

Malaysian Communications and Multimedia Commission Multiple Channel Per Carrier

Acronyms and Abbreviations in Telecommunications

MCPR MCR MCS

Multimedia Communication Processing and Representation Minimum Cell Rate (ATM) Master Control System

MCS

Multipoint Communication Service

MCTD

Maximum Cell Transfer Delay

MCT

Model Compatibility Test

MCU

Metered Calling Unit

MCVF

Multi-Channel Voice Frequency

MCU

Multipoint Control Unit

MCW

Modulated Continuous Wave

MDB

Management Database

MD

MDBS MDF

MDIS MDN MDN

MDNS

Mediation Device

Mobile Database Station

Main Distribution Frame

Mobile Data Intermediate System

Message Disposition Notification Mobile Directory Number

Managed Data Network Service

MDR

Memory Data Register

MDT

Manufacturer’s Delegated Testing

MDS

MDT

MDTRS ME ME

Moderate Speed Digital Subscriber Line Mean Downtime

Mobile Digital Trunked Radio Systems

Maintenance Entities Mobile Equipment

81

82

MEA

MEECN MEF

MEG

MEO

MEOS MERS MES

Acronyms and Abbreviations in Telecommunications

Modern Equivalent Asset

Minimum Essential Emergency Communications Network Maintenance Entity Function

Mobile Experts Group

Medium Earth Orbit

Medium Earth Orbit Satellites

Most Economical Route Selection

Master Earth Station

MExE

Mobile Station Application Execution Environment

MF

Medium Frequency

MF MF

MFD

MFLOPS MFSK

Mediation Function Multi Frequency

Mode Field Diameter

Millions of Floating Point Operations Per Second Multiple Frequency-Shift Keying

MG

Master Group

MHF

Medium High Frequency

MGW MHRP MHS MHS MHS

MHz, Mhz MIB

MIC

Media GateWay

Multi Host Routing Protocol

Message Handling Service Message Handling Source

Message Handling System

Megahertz

Management Information Base

Management Integration Consortium

Acronyms and Abbreviations in Telecommunications

MIC

Medium Interface Connector

MIC

Microphone

MIC

Minimum Ignition Current

MIC MIC MIC

MICP MID MID

Microwave Integrated Circuit Monolithic Integrated Circuit Mutual Interface Chart

Mobile Internetworking Control Protocol Message Identifier (ATM SMDS) Multiplexing Identifier (ATM)

MIDA

Multiple Integrated Digital Access (UK)

MIL-STD

Military Standard (US)

MILNET MIME

Military Network (US)

Multipurpose Internet Mail Extension

MIN

Mobile ID Number

MIPS

Millions of Instructions per Second

MIP MIS

Medium Interface Point

Management Information Services

MIS

Management Information System

MIX

Multiservice Interchange

MLC

Multilink Control Field (X25)

MLP

Multilink Protocol (X25)

MIT

MJPEG MLE

MLPP MLS

Massachusetts Institute of Technology Multi Joint Photography Experts Group

Maximum Likelihood Estimator Multilevel Precedence And Preemption

Mobile Location Services

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84

MLS

Acronyms and Abbreviations in Telecommunications

Multiple Listing Service

MMB

Milli-Metric Band (ETSI)

MMF

MultiMode Fibre

MMDS MMI

MMoIP MMP MMS

MMSI

Multichannel Multipoint Distribution System

Man Machine Interface

Multimedia Mail over IP

Multichassis Multilink PPP

Multimedia Message Service

Maritime Mobile Service Identities

MNO

Mobile Network Operator

MO

Magneto-Optical Modem Modulator/Demodulator

MNP

Mobile Number Portability

MOC

Mobile Originating Call

MOD

Demodulation

MOD

Modification

MOCVD MOD MOD

Modem

Metallo-Organic Chemical Vapour Deposition

Model

Modulation

Modulator-Demodulator

MOH

Music on Hold

MOP

Maintenance Operations Protocol

MOM

Method of Movements

MOS

Mean Opinion Score (voice quality score)

MOU

Minutes of Use

MoU MP

Memorandum of Understanding Multiplexing

Acronyms and Abbreviations in Telecommunications

MP3

MPEG Audio Layer 3

MPC

Multi Frequency Code

MPF

Metallic Path Facility

MPEG MPLS

Motion Pictures Expert Group MultiProtocol Label Switching

MPOA

Multiprotocol over ATM

MPPP

Multilink Point-to-Point Protocol

MPP

MRA

Multichannel Point-to Point Protocol

Mutual Recognition Agreement

MRCF

Maximum Rate of Exchange of Frequency

MS

Mobile Station

MS

Managed Services

MSB

Most Significant Bit

MSC

Mobile Switching Centre

MSE

MExE Service Environment

MSC MSDT MSG MSI

MSIN

MSISDN MSISDN MSK

MSN

MSO

Mobile Switching Centre Multi-Services Distant Terminal

Message

Mid-Span Interconnection

Mobile Station Identification Number

Mobile Subscriber International Subscriber Identity Number Mobile Station International ISDN Minimum Shifting Key

Microsoft Network

Mobile Switching Office

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Acronyms and Abbreviations in Telecommunications

MSO

Multiple Service Operator

MSRN

Mobile Station Roaming Number

MSS

MAN Switching System

MSP MSS

MSSHO

MS-SPRING MST MT

MTA MTA

Multiplex Section Protection

Mobile Satellite Systems

Mobile Speed Sensitive Handover

Multiplex Section Shared Protection Ring

Multi-Service Terminal

Mobile Termination

Mail Transport Agent

Message Transfer Agent

MTBF

Mean Time Between Failures

MTBO

Mean Time Between Outages

MTC

Mobile Terminated Call

MTP

Message Transfer Part

MTBM MTBPM MTF

MTP

Mean Time Between Maintenance Mean Time Between Preventive Maintenance

Modulation Transfer Function Multicast Transport Protocol

MTS

Message Telecommunications Service

MTS

Message Transfer System

MTS MTSO MTSR

MTTR MTU

Message Toll Service

Mobile Telephone Switching Office Mean Time to Service Restoral

Mean Time to Repair

Maximum Transmission Unit

Acronyms and Abbreviations in Telecommunications

MTU

Multi-Tenant Unit

MU

Message Unit

muldem

Multiplexer/Demultiplexer

MUX

Multiplexer

MUF

MUNDI

Maximum Usable Frequency

Multiplexed Network for Distributive and Interactive Services

MUXing

Multiplexing

MVDS

Multipoint Video Distribution System

MVDS MVIP

Microwave Video Distribution System

Multi Vendor Integration Protocol

MVNO

Mobile Virtual Network Operator

MVS

Multiple Virtual Storage

MVPRP MWI

MWV

Multivendor Problem Resolution Process

Message Waiting Indicator

Maximum Working Voltage

87

N

88

Acronyms and Abbreviations in Telecommunications

NA

Network Adaptor

NA

Numerical Aperture

NA

Network Aspects

NACD

Network Automatic Call Distribution

NACSEM

National Communications Security Emanation Memorandum

NACS

NACSIM NADF

NetWare Asynchronous Communication Services

National Communications Security Information Memorandum North American Directory Forum

NADN

Nearest Active Downstream Neighbour

NAM

Numeric Assignment Module

NAK

NAMAS

N-AMPS NANOG NANP

NANPA

Negative Acknowledgement

National Measurement Accreditation Service

Narrowband Advanced Mobile Phone System

North American Network Operator’s Group North American Numbering Plan

North American Numbering Plan Administration

NAP

Network Access Point (Internet)

NASA

National Aeronautics and Space Administration

NATA

North American Telecommunications Allocation

NAP NAT

NAU

NAUN

Network Access Provider (US)

Network Address Translation

Network Addressable Unit

Nearest Active Upstream Neighbour

Acronyms and Abbreviations in Telecommunications

NAVSTAR-GPS

Navigational Satellite Timing and Ranging--Global Positioning System

NB

Notified Body

NBFM

Narrowband Frequency Modulation

NBDP

Narrow Band Direct Printing

NBH

Network Busy Hour

NBRVF

Narrowband Radio Voice Frequency

NBMA NBSV

NonBroadcast MultiAccess Narrowband Secure Voice

NC

Network Computer

NCC

Namibian Communications Commission

NCC

Network Control Centre

NCA NCC NCCF

National Communications Authority (Ghana)

Nigerian Communications Commission

Network Communication Control Facility

NCCN

Network Charge Change Notice

NCO

Numerical Control Oscillator

NCP

Network Connection Point

NCC

NCOP NCP NCP NCP NCS NCS

NCSC

New Common Carrier (Japan) Network Code of Practice

Network Configuration Process Network Control Point

Network Control Programme

National Communications System

Net Control Station

National Communications Security Committee

89

90

Acronyms and Abbreviations in Telecommunications

NCTE

Network Channel Terminating Equipment

NDIS

Network Device Interface Standard

NE

Network Element

NECA

National Exchange Carrier Association

NDCS NDS

NEBS NEF

NEMS NEP

NER NES

NET

Network Data Control System Network Distribution System

New Equipment Building Specifications Network Element Function Block

Network Element Management Server

Noise Equivalent Power

Network Efficiency Ratio Noise Equivalent Signal

Norme Europeenne de Telecommunications

NetBEUI

NetBIOS Extended User Interface

NETC

National Electronics Test Centre (Ireland)

NetBIOS NETID NEXT NF

Network Basic Input/Output System Network Identifier

Near End Cross Talk

Noise Figure

NGN

Next-Generation Network

NHRP

Next Hop Routing Protocol

NHH NHS NI

NIC NIC

National Communications Authority (Hungary)

Next Hop Server

Network Interface

Network Information Centre (Internet Registry)

Network Interface Card (LAN)

Acronyms and Abbreviations in Telecommunications

NICC

Network Interoperability Consultative Committee

NICS

NATO Integrated Communications System

NICE NID NID NID

Network Information and Control Exchange Network Information Database Network Interface Device

Network Inward Dialling

NII

National Information Infrastructure

NIS

Network Information Service

NIOD N-ISDN NIST NIT

Network Inward/Outward Dialling

Narrow-band Integrated Services Digital Network (ISDN)

National Institute of Standards and Technology (US)

Networking Interworking Tests

NIU

Network Interface Unit

NL

Network Layer

NIUF NL

NLD

NLDM NLP

NLPID NLSP NM NM

NMC

NMDS

North American ISDN Users Forum Number of Unallocated Channels on Link National Long Distance

Network Logical Data Manager

National Level Programme

Network Layer Protocol Identifier NetWare Link Services Protocol

Network Management

Network Module

Network Management Centre

Narrow-band Multi-service Delivery System

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92

NML/NMS NMP

Acronyms and Abbreviations in Telecommunications

Network Management Layer/Network Management Service Network Management Protocol

NMR

Nuclear Magnetic Resonance Scanner

NMSI

National Mobile Station Identification Number

NN

Network Node

NNI

Network Node Interface (ATM)

NOA

Nature of Address

NMS

NMT NNG NNI

NOAF NOC

Network Management System

Nordic Mobile Telephone System

National Number Group

Network-to-Network Interface Network Operator Facility

Network Operations Centre

NOCC

Network Operations Control Centre

NORC

Network Operators Research Committee

NP

Network Performance

NOD NOS NP

NPA

Network Outward Dialling

Network Operating System Number Portability

Numbering Plan Area

NPC

Network Parameter Control (ATM)

NPI

Numbering Plan Identification

NPT

Norwegian Post and Telecommunications Authority

NPDU NPR

Network Layer Protocol Data Unit

Noise Power Ratio

Acronyms and Abbreviations in Telecommunications

NRA

NREN NRI

NRM NRM

National Regulatory Authority

National Research and Education Network (US)

Net Radio Interface

Network Resource Manager Normal Response Mode

NRZ

Non-Return-to-Zero

NRZ-S

Non-Return-to-Zero Space

NRZ-M NS/EP NSA

NSAP

NSAPA

Non-Return-to-Zero Mark

Telecommunications National Security or Emergency Preparedness Telecommunications National Security Agency (US) Network Service Access Point

Network Service Access Point Address

NSC

Network Service Centre

NSOs

National Standards Organisations

NSP

Native Signal Processing

NSS

Network Switching Sub-System (GSM)

NSF

NSP NSP

National Science Foundation (US) Network Service Provider

Network Service Protocol

NSS

Network Subsystem

NSTAC

National Security Telecommunications Advisory Committee (US)

NSSG NT NT

NTA

Network Solutions and Service Group

Network Termination (ISDN) New Technology

Nepal Telecommunications Authority

93

94

Acronyms and Abbreviations in Telecommunications

NTC

National Telecommunications Commission (Philippines)

NTE

Network Terminating Equipment

NTCN

National Telecommunications Coordinating Network

NTI

Network Terminating Interface

NTN

Network Terminal Number

NTMS NTO NTP NTP

NTRA NTRC NTRC NTS

NTSA NTSC NTT

NTTA NTU

NVRAM

NVT ASCII NXX

National Telecommunications Management Structure

Network Terminal Option

Network Termination Point Network Time Protocol

National Telecommunications Regulatory Authority of Egypt National Telecommunications Regulatory Commission (St Lucia) National Telecommunications Regulatory Commission (St Vincent and the Grenadines) Number Translation Services

Networking Technical Support Alliance

National Television Standards Committee Nippon Telegraph & Telephone (Japan)

Network Termination and Testing Apparatus

Network Termination Unit NonVolatile RAM

Network Virtual Terminal ASCII Nailed Line

Network Numbering Exchange

O

Acronyms and Abbreviations in Telecommunications

O&M

Operations and Maintenance

OAC

Operator Assisted Calls

OB

Outside Broadcast

OA&M OAM&P

Operations, Administration and Maintenance

Operations, Administration, Maintenance and Provisioning

OBC

Out-of-Band Connection

OC

Operations Centre

OBM OC

Optimised Bandwidth Management

Optical Carrier (SONET)

OCC

Other Common Carriers

OCHC

Operator Call Handling Centre

OCCA OCR

Open Cooperative Computing Architecture Optical Character Recognition

OCR

Optical Character Reader

OCU

Orderwire Control Unit

OCTPR OD

ODA

Office of the Commissioner of Telecommunications & Postal Regulation (Cyprus)

Optical Density

Open Document Architecture

ODBC

Open Database Connectivity

ODI

Open Data-Link Interface

ODS

Operational Data Store

ODF

ODIF

Optical Distribution Frame

Open Document Interchange Format

95

96

ODSI

OECD

Acronyms and Abbreviations in Telecommunications

Open Directory Services Interface

Organisation for Economic Cooperation and Development

OEIC

Opto-Electronic Integrated Circuit

OFC

Optical Fibre, Conductive

OFCOM

Office of Communications (UK)

OEM

OFCOM OFCP

Original Equipment Manufacturer

Office Fédéral de la Communication (Switzerland - see also BAKOM) Optical Fibre, Conductive, Plenum

OFCR

Optical Fibre, Conductive, Riser

OFM

Optical Frequency Multiplexing

OFDM

Orthogonal Frequency Division Multiplex

OFN

Optical Fibre, Nonconductive

OFNR

Optical Fibre, Nonconductive, Riser

OID

Object Identifier

OLAP

Online Analytical Processing

OFNP OHD OIM

Optical Fibre, Nonconductive, Plenum On Hook Dialling

OSI Internet Management

OLC

Optical Loop Carrier

OLO

Other Licensed Operator

OLR

Overall Loudness Rating

OLI

OLO OLTE OMA

Optical Line Inlet

Optical Line Outlet

Optical Line Terminating Equipment Object Management Architecture

Acronyms and Abbreviations in Telecommunications

OMA

Open Mobile Alliance

OMC

Operations and Maintenance Centre

OMERT

Office Malagasy d’Études et de Régulation des Télécommunications (Madagascar)

OME OMF

Operator Mobile Exchange

Object Management Framework

OMG

Object Management Group

OMT

Operations and Maintenance Terminal

OMP

Open Market Provision

ONA

Open Network Architecture

ONC

Open Network Computing

ONP

Open Network Provision

ONAL ONMS ONPCCP ONU

Off-Network Access Line

Open Network Management System

ONP Consultative and Co-ordination Platform

Optical Network Unit

OOE

Organisation Outside ETSI

OPEX

Operating Expanditures

OOP opm

OPMODEL OPSEC OPTA OPX

OQPSK OR

Object-Oriented Programming Operations Per Minute Operations Model

Operations Security

Onafhankelijke Post en Telecommunicatie Authoriteit (NRA of the Netherlands) Off Premises Extension

Orthagonal Quadrature PSK

Off-Route Aeronautical Mobile Service

97

98

Acronyms and Abbreviations in Telecommunications

ORB

Object Request Broker

ORM

Optically Remote Switching Module

ORDR

Optical Time Domain Reflectometry

OS

Operations Systems

OSF

Open Software Foundation

OSA OSF

OSHA

Open Service Architecture

Operations Systems Function Block

Occupational Safety and Health Administration (US)

OSI

Open Switching Interval

OSI/NMF

OSI Network Management Forum

OSI OSINET

OSIPTEL OSI-RM OSIRM

OSITOP OSP

OSPF

Open Systems Interconnection (ISO interface specifications) OSI Network

Organismo Supervisor de Inversión Privada en Telecomunicaciones (Peru)

Open Systems Interconnection--Reference Model

Open Systems Interconnection Reference Model (ISO ITU-T) Open Systems Interconnection/Technical and Office Protocol Outside Plant

Open Shortest Path First

OSRI

Originating Stations Routing Indicator

OSS

Operation Support Systems

OTA

Over-the-Air

OSS

OSSN

One Stop Shopping

Originating Stations Serial Number

Acronyms and Abbreviations in Telecommunications

OTAM OTAR

OTDR

Over-the-Air Management of Automated HF Network Nodes Over-the-Air Rekeying

Optical Time Domain Reflectometer

OTE

Operator Tandem Exchange

OUI

Organisational Unique Identifier

OW

Orderwire

OTRT OUR

Office Tchadien de Régulation des Télécoms (Chad)

Office of Utilities Regulation (Jamaica)

99

P

100

Acronyms and Abbreviations in Telecommunications

p/a r

Peak-to-Average Ratio

P2P

Person-to-Person

P/P

PABX

Point-to-Point

Private Automatic Branch Exchange

PAC

Programme Advisory Committee (ETSI)

PACS

Personal Access Communications System

PACE

Priority Access Control Enabled

PACT

Public Access Cordless Telephony

PAL

Phase Alternation by Line (colour TV standard)

PAM

Pulse Amplitude Modulation

PAMR

Public Access Mobile Radio

PAD

PAL-M PAMA PAMS PAN PAP

Packet Assembler/Disassembler

Phase Alternation by Line - Modified Pulse-Address Multiple Access

Perceptual Analysis / Measurement System (ITU-based standard P.800) Personal Area Network

Password Authentication Protocol

PAR

Performance Analysis And Review

PAT

Port Address Translation

PARAMP PAX

Parametric Amplifier

Private Automatic Exchange

PBER

Pseudo-Bit-Error-Ratio

PBX

Private Branch Exchange

PBP

Packet Burst Protocol

Acronyms and Abbreviations in Telecommunications

PC

Carrier Power (of a radio transmitter)

PC

Path Control

PCA

Position of Closed Approach

PC

Printed Circuit

PCB

Power Circuit Breaker

PCB

Process Control Block

PCC

Prepaid Calling Card

PCB PCB

PCC

PCH

Printed Circuit Board

Public Call Box (payphone)

Primary Cross Connect Paging Channel

PCI

Peripheral Component Interconnect

PCI

Programmable Communication Interface

PCI

Pre-Connection Inspection

PCI

Protocol Control Information

PCM

Plug Compatible Module

PCIA PCM PCM

PCMCIA

Personal Communications Industry Association Process Control Module Pulse Code Modulation

Personal Computer Memory Card Industry Association

PCN

Personal Communications Network

PCO

Public Call Office

PCS

Personal Communication Services

PCN PCR PCS

101

Personal Communications Number Peak Cell Rate (ATM)

Personal Communication Space

102

PCS

Acronyms and Abbreviations in Telecommunications

Personal Communication System

PCS

Plastic-Clad Silica (fibre)

PCS1900

Personal Communications System 1900 MHz

PCS

PCSN PCSR PCT

Port Concentrator Switch

Private Circuit Switching Network Parallel Channels Signalling Rate

Private Communication Technology

PCU

Premises Control Unit

PDC

Personal Digital Cellular

PDE

Positioning Determination Entity

PDH

Plesiochronous Digital Hierarchy

PDA

PDD PDF

PDM

Personal Digital Assistant Post Dial Delay

Portable Document Format

Pulse-Duration Modulation

PDN

Packet Data Network

PDS

Power Distribution System

PDN PDS

PDT

PDU

Public Data Network

Protected Distribution System

Programmable Data Terminal

Protocol Data Unit

PE

Phase-Encoded

PEAN

Pan-European ATM Network

PE

PED

PEM

Public Enquiry

Portable Electronic Devices Privacy Enhanced Mail

Acronyms and Abbreviations in Telecommunications

PEP

PESQ PET PF, pf PF

PFD

PFM

PGT-10 PH

Peak Envelope Power (of a radio transmitter)

Perceptual Evaluation of Speech Quality (ITU-standard P.862) Planning Exercise in Telecommunications technologies (forerunner of RACE) Picofarad

Power Factor

Power Flux Density

Pulse-Frequency Modulation

The Conference of European Postal and Telecommunications Administrations’ general tariff principles study group. Personal Handyphone System

PHY

Physical Layer

PI

Protection Interval

PHY PI

PIC

Physical Sublayer

Programming Infrastructure

Plastic Insulated Cable

PIC

Primary Interexchange Carrier (US)

PIM

Personal Information Manager

PICS PIM

PIM DM PIM SM

Protocol Implementation Conformance Statement Protocol Independent Multicast PIM Dense Mode

PIM Sparse Mode

PIN

Personal Identification Number

ping

Packet Internet Groper

PIN

103

Positive-Intrinsic-Negative

104

Acronyms and Abbreviations in Telecommunications

PINX

Private Telecommunications Network Exchange

PIV

Peak Inverse Voltage

PITCOM

Parliamentary Information Technology Committee (UK)

PIXIT

Protocol Implementation Extra Information for Testing

PKI

Public Key Infrastructure

PKC PL PL

PLAR

Public Key Cryptology

Private Line Project Line

Private Line, Automatic Ringdown

PLC

Power Line Communications

PLCP

Physical Layer Convergence Procedure

PLC

PLIM

Programming Logic Controller

Physical Layer Interface Module

PLISO

Plesisochronous

PLMN

Public Land Mobile Network

PLL

Phase-Locked Loop

PLN

Private Line Network

PLR

Pulse Link Repeater

PLP PLS

PLSP

Packet Layer Protocol (X25)

Physical Signalling Sublayer PNNI Link State Packets

PLU

Primary Logical Unit

PM

Phase Modulation

PM PM PM

Mean Power

Physical Medium

Polarisation-Maintaining (optical fibre)

Acronyms and Abbreviations in Telecommunications

PM

Preventive Maintenance

PMA

Physical Medium Attachment

PMBX

Private Manual Exchange System

PM

PMBS PMD

PMN

Pulse Modulation

Packet Mode Bearer Service

Physical Medium Dependent (FDDI)

Public Mobile Network

PMO

Programme Management Office

PNNI

Private Network Node Interface (ATM)

PnP

Plug-and-Play

PMR PNO PNT

Private Mobile Radio

Public Network Operator

Private Network Termination

POC

Point of Connection

POET

Packet Over E3/T3

POD

Programmable Option Devices

POI

Point Of Interconnect

POP

Point of Presence

PON POP PoS

Passive Optical Network Post Office Protocol Point Of Sale

POSI

Promotion of OSI

POSIX

Portable Operating System Interface for Computer Environments

POSIT

POSTEL

Profiles for Open Systems Interworking Technologies

Directorate General of Posts and Telecommunications (Indonesia)

105

106

POTRAZ POTS P-P PP

PPC

Acronyms and Abbreviations in Telecommunications

Postal and Telecommunications Regulatory Authority of Zimbabwe Plain Old Telephone Service

Peak-to-Peak

Polarisation-Preserving (optical fibre)

Pay-Per-Call

PPCC

Prepaid Calling Card

PPP

Point-to-Point Protocol

PPM PPS

Pulse-Position Modulation

Precise Positioning Service

PPS

Pulses per Second

PQA

Product Quality Assurance

PRBS

Pseudo Random Bits Sequence

PPV PR

PRD PRF

Pay-per-View

Pulse Rate

Programme Reference Document

Pulse-Repetition Frequency

PRI

Primary Rate Interface (ISDN)

PRMD

Private Management Domain

PRM PRN

PROM PRP

Pulse-Rate Modulation

Pseudo Random Noise

Programmable Read-Only Memory Primary Routing Point

PRR

Pulse Repetition Rate

PRSIG

Pacific Rim SMDS Interest Group

PRS

Premium Rate Service

Acronyms and Abbreviations in Telecommunications

PRSL PS PS PS PS

PSB

PSC

PSD

PSDN

Primary Area Switch Locator

Packet Switched

Paging Systems

Permanent Signal

Power Supply

Public Service Board

Public Service Commission (US) Power Spectral Density

Packet Switched Data Network

PSE

Packet Switching Exchange

PSN

Packet-Switched Network

PSN

Public Switched Network

PSK

PSN PSP

PSPDN PSQM PST

PSTN PSU PT

PTA PTA

PTD PTF

107

Phase Shift Keying

People with Special Needs Personal Software Products

Packet Switched Public Data Network

Perceptual Speech Quality Measurement (ITU-standard P.861) Plug-and-Socket Terminated

Public Switched Telecommunications Network

Power Supply Unit

Payload Type

Pakistan Telecommunication Authority

Post and Telecom Administration (Iceland)

Post and Telegraph Department (Thailand)

Patch And Test Facility

108

Acronyms and Abbreviations in Telecommunications

PTI

Packet Type Identifier (X25)

PTM

Packet Transport Mode

PTI

Payload Type Identifier (ATM)

PTM

Plesiochronous Transmission

PTN

Public Telecommunication Network

PTO

Public Telecommunication Operator

PTS

Public Telecommunications System

PTM PTNX PTS

Pulse-Time Modulation

Private Telecommunications Network Exchange National Post and Telecom Agency (Sweden)

PTT

Post, Telephone and Telegraph

PTTC

Paper Tape Transmission Code

PTT

PTTI PU

Push-to-Talk

Precise Time And Time Interval

Pick-Up

PU

Power Unit

PUC

Public Utilities Commission (US)

PVC

Permanent Virtual Circuits

PU

PURA PVC

PVN PVP PW

PWB

PWM

Physical Unit

Public Utility Regulatory Authority (Gambia) Polyvinyl Chloride

Private Virtual Network

Permanent Virtual Paths

Private Wire

Printed Wiring Board

Pulse-Width Modulation

Acronyms and Abbreviations in Telecommunications

PWT PX

PXML

Personal Wireless Telephone

Private Exchange

Private Exchange Master List

109

Q

110

Q3

QA QA

QAFQ

Acronyms and Abbreviations in Telecommunications

Network Management Interface (ITU-T)

Quality Assurance

Q-Adapter (TMN)

Adapter Block (TMN)

QAIG

Signalling in Q-Point (private ISDN networks)

Q-bit

Qualified Data Bit (X25)

QAM QC

Quadrature Amplitude Modulation

Quality Control

QCIF

Quarter CIF

QLLC

Qualified Logical Link Control

QI

QMR QoS

QPD

Quality Index

Qualitative Material Requirement Quality of Service

Qualified Program Document

QPL

Qualified Product List

QPSX

Queued Packet Synchronous Exchange

QPSK QRC QRS

QRSS

Quadrature Phase Shift Key

Quick Reaction Capability Quasi-Random Signal

Quasi-Random Signal Sequence

QSIG

Unified international corporate network signalling standard

QUICK

Trenching Quicker Underground Integrated Cabling and Networking

QSTAG

Quadripartite Standardisation Agreement

R

Acronyms and Abbreviations in Telecommunications

R R

R&D R/T RA

Receiver

Route Service

Research & Development Real Time

Remote Access

RAC

Relay Access Card

RACH

Random Access Channel

RACE RADHAZ RADINT

Research and Development in Advanced Communications Technologies in Europe Electromagnetic Radiation Hazards

Radar Intelligence

RADIUS

Remote Dial-In User Service

RAIM

Receiver Autonomous Integrity

RADSL RAM RAM

Rate Adaptive Digital Subscriber Line

Random Access Memory

Reliability, Availability, And Maintainability

RAN

Radio Access Network

RARP

Reverse Address Resolution Protocol

RARE

Réseaux Associés pour la Recherche Européenne

RAS

Remote Access Server (Remote LAN)

RBBS

Residential Broadband Service

RBOC

Regional Bell Operating Companies (US)

RATT RBES RC

Radio Teletypewriter System

Rule-Based Expert Systems

Rate Centre

111

112

RC

Acronyms and Abbreviations in Telecommunications

Reflection Coefficient

RC

Reference Configuration

RC

Resource Controller

RC

Repeating Coil

RCC

Radio Common Carrier (US)

RCE

Remote Channel Extenders

RCC RCF

Reverse Control Channel Routing Control Field

RCO

RACE Central Office

RCU

Remote Control Unit

RCP

RCU

RCVR

Remote Copy Protocol

Remote Concentrator Unit Receiver

RD

Routing Domain (ATM ISO)

RD&T

Research Development and Technology

RD&E

RDBMS RDF

Research Development and Engineering Relational Database Management System

Route Designator Field

RDI

Remote Defect Identification

RDS

Radio Data Signal/System

RDP RDSS

RDTD RegTP REM

RACE Definition

Radio Determination Satellite Service

Restricted Differential Time Delay

Regulierungsbehörde für Telekommunikation und Post (German NRA) Ring Error Monitor

Acronyms and Abbreviations in Telecommunications

REN

Ringer Equivalent Number

RES

Radio Equipment and Systems

REP

RESP RET

Repeat

Response

Returning

RF

Radio Frequencies

RFH

Remote Frame Handler (ISDN)

RFA

Random Fixed Access

RFI

Radio Frequency Interference

RG

Research Group

RH

Relative Humidity

RFS RG

RHR RI

Ready for Service

Ring Ground

Radio Horizon Range

Routing Indicator

RIC

RACE Industrial Consortium

RII

Routing Information Indicator (Source Routing)

RIM

Receiver Intermodulation

RIF

RIM RIM

Routing Information Field (Source Routing) Radio Identity Model

Request Initialisation Mode (HDLC)

RIO

Reference Interconnection Offer

RISC

Reduced Instruction Set Computing

RJ

Registered Jack

RIP

RISE

Routing Information Protocol

Retrieval and Interchange of Standards in Europe

113

114

Acronyms and Abbreviations in Telecommunications

RJE

Remote Job Entry

RLR

Receive Loudness Rating

RLM RLSD RM

Redundant Link Manager

Receive Line Signal Detector

Resource Management

RMC

RACE Management Committee

RMU

Resource Management Units

RMON

Remote Network Monitoring

RNC

Radio Network Controller

RO

Read Only / Receive Only

ROC

Required Operational Capability

RNS

ROA ROCE ROH

Radio Network Subsystem

Recognised Operating Agency

Return on Capital Employed Receiver Off-Hook

ROI

Return On Investment

ROMP

Remote Operations Microprocessor

ROM RoR

Read-Only Memory Rate of Return

ROSE

Remote Operation Service Element (Application Layer)

RPC

Remote Procedure Call

RPI

Retail Price Index

RQ

Repeat-Request

RP

RPF

RPS

Registration Point

Reverse Path Forwarding Ring Parameter Server

Acronyms and Abbreviations in Telecommunications

RR

Radio Regulations (ITU)

RR

Register Recall (Timed Break)

RR

Repetition Rate

RR

115

Relative Rate

RRB

Radio Regulations Board

RSA

Rivest, Shamir, and Adelman (public-key cryptographic system)

RS

RSCV RSH RSL

RSM RSP

Remote Station

Route Selection Control Vector Remote Shell Protocol

Received Signal Level

Remote Switching Module

Route/Switch Processor

RSRB

Remote Source-Route Bridging

RSS

Remote Switch Subsystem

RSS

RSVP

Radio Subsystem

Resource Reservation Protocol

RT

Real Time

RT

Ringback Tone

RTA

Remote Trunk Arrangement

RT RT

RTC/RTS

Remote Terminal Routing Type

Regional Tele Centre/Regional Tele Server

RTCP

Real-Time Control Protocol

RTF

Rich Text Format

RTCP

RTP Control Protocol

116

Acronyms and Abbreviations in Telecommunications

RTP

Rapid Transport Protocol

RTP

Routing Table Protocol

RTP RTS

RTSC RTSE RTSP

RTTE RTTE-CA RTTY RTU RTU RTU

rt-VBR RTX

Real-Time Transport Protocol Request to Send

Regional Telematic Service Centre

Remote Transfer Service Element (Application Layer) Real Time Streaming Protocol

Radio and Telecommunication Terminal Equipment (also R&TTE) Radio and Telecommunication Terminal Equipment Compliance Association Radio Teletypewriter

Radio Termination Unit

Remote Telemetry Units Right to Use

Real Time Variable Bit Rate

Request to Transmit

RU

Request/Response Unit

RUO

Reference Unbundling Offer

RVWG

Reliability and Vulnerability Working Group

RUDP RVA RWI

RWT RX Rx

RXLEV

Reliable User Data Protocol

Reactive Volt-Ampere

Radio and Wire Integration Right When Tested

Receiver

Reception

Received Signal Level

Acronyms and Abbreviations in Telecommunications

RXQUAL RZ

Received Signal Quality Return-to-Zero

117

S

118

Acronyms and Abbreviations in Telecommunications

SxS

Step-by-Step

S/N

Signal to Noise Ratio

SA

Selective Availability

SA

Subscribers’ Apparatus

S/H S/R SA SA

SAA

SAACH

Sample and Hold

Send and Receive

Source Address

Switched Access

Systems Application Architecture (IBM) Slow Associated Control Channel

SAAL

Signalling ATM Adaptation Layer (ATM)

SABME

Set Asynchronous Balanced Mode Extended (HDLC)

SABM

Set Asynchronous Balanced Mode (HDLC)

SAC

Service Access Code

SAC

Stand-Alone Costs

SAC SAER SAM

Single-Attached Concentrator Service and Equipment Record System Administration Module

SAP

Service Advertising Protocol

SAPI

Service Access Point Identifier (LAPD)

SARM

Set Asynchronous Response Mode (HDLC)

SAP

SAR SAS

Source Access Point

Segmentation and Re-assembly (ATM) Simple Attachment Scheme

Acronyms and Abbreviations in Telecommunications

SAS

Single Attachment Station

SAS

Statically Assigned Socket

SATAN

System Administrator Tool for Analysing Networks

SAT SB

SBSVC SC

SIM Application Toolkit

Synchronisation Burst

Selective Broadcast Signalling Virtual Channel (BISDN) Self-Contained

SC

Signalling Converter

SC

Standards Committee (ISO)

SC SCA

SCADA

Switching Centre

System Communication Architecture Supervisory Control and Data

SCC

Specialised Common Carrier

SCDC

Single Commutation Direct Current

SCEF

Service Creation Environment Function

SCCP SCE SCF

SCH SCP SCP

Signalling Connection Control Part

Service Creation Environment Service Control Function

Synchronisation Channel

Service Control Point

Session Control Protocol

SCPC

Single Channel per Carrier

SCR

Silicon-Controlled Rectifier

SCR SCR

Semiconductor-Controlled Rectifier Sustained Cell Rate (ATM)

119

120

SCRA

Acronyms and Abbreviations in Telecommunications

Small Call Routing Apparatus

SCSI

Small Computer Systems Interface

SCTE

Society of Cable Telecommunications Engineers

S-DAB

Satellite Digital Audio Broadcasting

SDF

Specialised Database Functions (TMN)

SCSR

SCVF

SDCCH SDH SDK

SDLC SDLS SDM

Single Channel Signalling Rate

Single Channel Voice Frequency

Standalone Dedicated Control Channel

Synchronous Digital Hierarchy (ITU-T)

Software Development Kit

Synchronous Data Link Control

Single-Line Digital Subscriber Line Space Division Multiplexing

SDN

Software-Defined Network (AT&T)

SDSL

Single-Line Digital Subscriber Line

SDR

SDSU SDU SE SE

SECAM

Software Defined Radio

SMDS Data Service Unit

Service Data Unit

Support Entity

Support Equipment

Séquentiel à Mémoire (French colour TV standard)

SECORD

Secure Voice Cord Board

SEF

Support Entity Function

SECTEL SEMKO

Secure Telephone

Swedish Institute for Testing and Approval of Electrical Equipment

Acronyms and Abbreviations in Telecommunications

SES

Satellite Earth Stations

SETAMS

Systems Engineering, Technical Assistance, and Management Services

SET

SEVAS

121

Secure Electronic Transaction Secure Voice Access System

SEWG

Spectrum Engineering Working Group of CEPT ERC

SF

Single-Frequency

SFS

Single-Frequency Signalling

S-F SF

SFS SG

Store-and-Forward

Super Frame

Start of Frame Sequence (LAN)

Study Group (ITU-T)

SG

Supergroup

SGDF

Supergroup Distribution Frame

SGCP

SGML SGMP

Simple Gateway Control Protocol Standard Generalised Markup Language Simple Gateway Monitoring Protocol

SGNT

Special Grade Network Trunk

SHARES

Shared Resources HF Radio Programme

SGSN

Serving GPRS Support Node

SHF

Super High Frequency

SI

International System of Units

SIB

Service Independent Building Block

S-HTTP SI

SID

Service Hypertext Transport Protocol

Statutory Instrument (Ireland and UK) Sudden Ionospheric Disturbance

122

SID SIF

Acronyms and Abbreviations in Telecommunications

System ID Number

Signalling Information Field

SIG

SMD Interest Group

SIGET

Superintendencia General de Electricidad y Telecomunicaciones (El Salvador)

SIG

SIM

SIMD

SINAD SIN

SIO SIP SIP

SIR SIT

SITTEL

Special Interest Group

Subscriber Identity Module

Single Instruction Stream Multiple Data Stream

Signal-Plus-Noise-Plus-Distortion to Noise-PlusDistortion Ratio Suppliers Information Notes (British Telecom)

Scientific and Industrial Organisations (ITU-T) Session Initiation Protocol (IETF)

SMDS Interface Protocol

Sustained Information Rate (SMDS)

Superintendencia de Telecomunicaciones (Guatemala) Superintendencia de Telecomunicaciones (Bolivia)

SITA

Society of International Aeronautical Telecommunications

SJF

Shortest Job First

SLA

Service Level Agreement

SITS SKU SLC

SLEE SLI

SLIC SLIP

Special Investigation Test Schedule (UK)

Stock-Keeping Unit

Subscriber Loop Carrier

Service Logic Execution Environment

Service Logic Interpreter

Subscriber Loop Interface Circuit

Serial Line Internet Protocol (IETF)

Acronyms and Abbreviations in Telecommunications

SLM SLP

SLR

SLSA SLU

Service Level Management

Service Logic Program

Send Loudness Rating

Single Line Switching Apparatus

Sub-Loop Unbundling

SLUO

Sub-Loop Unbundling Operator

SMAF

Service Management Agent Function (TMN)

SMA

SMAP

SMART SMATV SMB

SMDR SMDS

Service Management Architecture

System Management Application Part

Strategy for Mobile Advanced Radio Telecommunications (initiative of DG XIII/D) Satellite Master Antenna Television

Server Message Block

Station Message Detail Recording

Switched Multimegabit Data Service (Bellcore)

SME

Small and Medium Size Business Enterprise

SMG

Special Mobile Group

SMF

SMG

Service Management Function (TMN)

Supermastergroup

SMI

Structure of Management Information

SML/SMS

Service Management Layer/Service Management Service

SMIP SMP SMP SMP SMP

Strategic Management Information Plan Significant Market Power

Simple Management Protocol Switching Module Processor Symmetric Multiprocessing

123

124

Acronyms and Abbreviations in Telecommunications

SMR

Specialised Mobile Radio

SMS

Satellite Multiservice System

SMRP SMS SMS

Simple Multicast Routing Protocol

Service Management System

Short Message Service

SMSC

Short Message Service Centre

SMT

Surface Mounting Technology

SMTP

Simple Mail Transfer Protocol

SMT

SMTA SN SN SN

Station Management

Single-Line Multi-Extension Telephone Apparatus

Sequence Number (ATM) Service Node

Station Number

SN

Subscriber Number

SNA

Special Network Access

SN

SNA

SNAP SNCP SNG

Switching Network

Systems Network Architecture (IBM) Subnetwork Access Protocol

Sub-Network Connection Protection

Satellite News Gathering

SNI

Subscriber Network Interface (SMDS)

SNP

Sequence Number Packet (NetWare)

SNMP SNP

SNPA SNR

Simple Network Management Protocol

Sequence Number Protection

Subnetwork Point of Attachment

Signal to Noise Ratio

Acronyms and Abbreviations in Telecommunications

SNRM

SNRME SO

Set Normal Response Mode (HDLC)

Set Normal Response Mode Extended (HDLC)

Switching Office

SOGIT/SOGITS

Senior Officials Group for Information Technology Standards

SOM

Start of Message

SOGT sonar

SONET SOP

SOR

Senior Officials Group for Telecommunications Sound Navigation and Ranging

Synchronous Optical Network

Standard Operating Procedure

Start of Record

SOW

Statement of Work

SP

Signalling Point

SP

SPAG

Service Provider

Standards Promotion and Application Group

SPARC

Scalable Performance Architecture

SPDU

Session Protocol Data Unit

SPCS SPF

Satellite Personal Communication Services Shortest Path First

SPID

Service Profile Identifier (ISDN)

SPM

Subscriber Private Meter

SPM

SPOC SPP

SPRK SPS

Space Switch Module

Single Point of Contact

Sequenced Packet Protocol

Public Utilities Commission (Latvia)

Signalling Protocols and Switching

125

126

Acronyms and Abbreviations in Telecommunications

SPS

Standard Postioning Service

SQE

Signal Quality Error

SR/TLB

Source-Route Translational Bridging

SPTN SQL

SRAM SRB

Single Protocol Transport Network

Structured Query Language

Static Random Access Memory (RAM)

Source-Route Bridging

SREJ

Selective Reject (HDLC)

SRI

SIP Relay Interface (SMDS)

SRF

Specialised Resources Function (TMN)

SRIC

Short Run Incremental Costing

SRP

Specialised Resource Point (IN)

SRNC SRT

Serving Radio Network Controller Source-Route Transparent Bridging

SRT

Source Routing Transparent

SRTS

Synchronous Residual Time Stamp

SS

Spread Spectrum

SS

Supplementary Service

SS7

Signalling System No. 7

SRTP SRTT SS SS6 SSAP SSB SSB

Sequenced Routing Table Protocol

Satellite Radio Transmission Technologies

Switching System

Signalling System No. 6 Source Service Access Point

Service Selection Barring Single Side Band

Acronyms and Abbreviations in Telecommunications

SSBSC

Single Sideband Suppressed Carrier

SSH

Secure Shell Encryption

SSF

Service Switching Function

SSL

Signal Station Location

SSN

Station Serial Number

SSP

Switch-to-Switch Protocol

SSM SSP

Single Segment Message (DQDB SMDS)

Service Switching Point

SSR

Solid-State Relay

SSSO

Specialised Satellite Services Operator

SST

Synchronous Service Transport

SSS

SST

SSUPS ST

Subscriber Switching Subsystem Spread Spectrum Technology

Solid-State Uninterruptible Power System

Signalling Terminal

STAG

Security Techniques Advisory Group (ETSI)

STBX

Set Top Box

STD

Synchronous Time Division

STAX STD

STDM

Standardisation Reference Database Subscriber Trunk Dialling

Statistical Time Division Multiplexing

STE

Signalling Terminal Equipment

STEM

Strategic Telecommunication Evaluation Model

STE

STFS STL

Spanning-Tree Explorer (LAN)

Standard Time and Frequency Signal

Standard Telegraph Level

127

128

Acronyms and Abbreviations in Telecommunications

STL

Studio-to-Transmitter Link

STM

Synchronous Transport Module (SDH)

STM STMR STP

Synchronous Transfer Mode

Sidetone Masked Loudness Rating

Shielded Twisted-Pair

STP

Signalling Transfer Point

STS

Synchronous Transport Signal (SONET)

STP

Standard Temperature and Pressure

STU

Secure Telephone Unit

SUBT

Subscriber Terminal

SVC

Signalling Virtual Channel (ATM)

STX

SUBTEL SVC SW

SWG SWR

Start of Transmission

Subsecretaría de Telecomunicaciones (Chile) Switched Virtual Circuit (Packet Switching)

Software

Standard Wire Gauge Standing Wave Ratio

SX

Simplex Signalling

SYNTRAN

Synchronous Transmission

SXS

SYSGEN

Step-by-Step Switching System

System Generation

T

Acronyms and Abbreviations in Telecommunications

TA

Terminal Adapter (ISDN)

TAC

Terminal Access Controller

TACS

Total Access Communications Systems

TABS TACACS TADIL TADS

TADSS

Telemetry Asynchronous Block Serial

Terminal Access Controller Access Control System Tactical Data Information Link

Teletypewriter Automatic Dispatch System

Tactical Automatic Digital Switching System

TAG

Technical Advisory Group

TAP

Transfer Account Procedure

TAPI

Telephony API

TAS

Suriname Telecommunications Authority

TAM TAP

TARM

Telecommunications Authority of Maldives

Transmission Access Point

Telephone Answering and Recording Machine

TASI

Time Assigned Speech Interpolation

TAXI 4B/5B

Transparent Asynchronous Transmitter/Receiver Interface 4-byte/5-byte

TAT TB

Trans-Atlantic Telecommunication (cable)

Technical Body (ETSI)

TB

Time Break

TBB

Trans-National Broadband Backbone

TB

Tbps

TBR

Transparent Bridging

Terabit Per Second

Technical Basis for Regulation (ETSI)

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130

TBR

Acronyms and Abbreviations in Telecommunications

Time Break Recall

TC

Toll Centre

TC

Transmission Convergence

TC TC

TCA

TCAM

Transmission Control

Transport Connection

Time of Closest Approach

Telecommunications Access Method (SNA)

TCAP

Transaction Capabilities Application Part

TCC

Telecommunications Centre

TCCF

Tactical Communications Control Facility

T-Carrier TCC TCF

Trunk Carrier

Terminating Call Control

Technical Construction File (EU R&TTE)

TCF

Technical Control Facility

TCIF

Telecommunications Industry Forum

TCM

Time Compression Multiplexing

TCH TCL TCP

TCP/IP TCRA

Traffic Channel

Interface Tool Command Line Interface Transport Control Protocol

Transmission Control Protocol /Internet Protocol (IETF)

Tanzania Communications Regulatory Authority

TCRL

Test Case Reference List

TCU

Telecommunications Control Unit (SNA)

TCS

TCU

Trusted Computer System

Trunk Coupling Unit

Acronyms and Abbreviations in Telecommunications

TCVXO

Temperature Compensated-Voltage Controlled Crystal Oscillator

TCXO

Temperature Controlled Crystal Oscillator

TD

Transmitter Distributor

TD

Time Delay

T-DAB

Terrestrial Digital Audio Broadcasting

TDD

Telecommunications Device for the Deaf

TDF

Time Division Filtering

TD-CDMA TDD TDM

Time Division Code Division Multiple Access

Time Division Duplexing

Time Division Multiplexing

TDMA

Time Division Multiple Access

TDMS

Transmission Distortion Measuring Set

TDMS

TDOA TDR

TDRSS

Time Division Multiplex System

Time Difference of Arrival

Time Domain Reflectometer

Tracking and Relay Satellite System

TDS

Time Division Switching

TE

Techno-Economic Evaluation

TE1

Terminal Equipment Type 1 (ISDN capable)

TD-SCDMA TE

TE2

TE&DA TEAM TED

Time Division Synchronised CDMA

Terminal Equipment

Terminal Equipment Type 2 (non-ISDN)

Techno-Economic Evaluation & Demand Analysis Techno-Economic Ad Hoc Meeting

Trunk Encryption Device

131

132

TEDIS TEHO

Acronyms and Abbreviations in Telecommunications

Trade Electronic Data Interchange Systems

Tail End Hop Off

TEI

Terminal Endpoint Identifier (LAPD)

TELCO

Telecommunications Company

TELRIC

Total Element Long Run Incremental Costs

TEK

TELCOR TEM

TEMA TeMIP TEMPEST TEMS

TERENA TeT

TETRA TFT

TFTP TFTS

Traffic Encryption Key

Instituto Nicaraguense de Telecomunicaciones y Correos (Nicaragua) Transverse Electric And Magnetic

Telecommunications Equipment Manufacturers Association

Telecommunications Management Information Platform (Compaq) Compromising Emanations

Telecommunications Management System

Trans-European Research and Education Networking Association Techno-Economic Oriented Tools Trans European Trunked Radio

Thin-Film Transistor

Trivial File Transfer Protocol

Terrestrial Flight Telephone System

TG

Trunk Group

THD

Total Harmonic Distortion

TGM THF

THL

Trunk Group Multiplexer

Tremendously High Frequency

Trans Hybrid Loss

Acronyms and Abbreviations in Telecommunications

THz

Terahertz

TI

Telecom Instruction

TIBS

Telecommunication Input Billing System (UK)

TIA

Telecommunications Industry Association (UK)

TIC

Token Ring Interface Coupler

TIE

Time Interval Error

TIG

Terminal Interoperability Group

TINA

Telecommunications Information Networking Architecture

TID TIFF TIM

TIOS TIP

TIPHON TIRKS TIS TJF TK

TKK

Terminal Identifier

Tag Image File Format

Transmitter Intermodulation

Transpath Input and Output Subsystem Terminal Interface Processor

Telecommunications & Internet Protocol Harmonisation Over Networks Trunk Information Record Keeping System (US)

Technical Information Sheets

Test Jack Frame

Response Timer

Telekom-Control-Kommission (Austria)

TL

Transmission Level

TLP

Transmission Level Point

TLS

Transparent LAN Service

TLH TLP TLS

133

Transport Layer Header

Transmission Level Point

Transport Layer Security (IETF)

134

TM

Acronyms and Abbreviations in Telecommunications

Terminal Multiplexer

TM

Transmission and Multiplexing

TMF

Telecommunications Management Forum

TMA

Telecommunication Managers Association (UK)

TMN

Telecommunications Management Network

TMS

Time-Multiplexed Switch

TMRS TMS

TMSI

Traffic Measurement and Recording Systems

Transport Management System

Temporary Mobile Subsciber Identity

TO

Tandem Office

TO

Toll Office

TO TOA

Telecommunications Operator Time of Arrival

TOC

Turn of Cycle

TOPS

Traffic Operator Position System

TOP ToR

Technical Office Protocol Terms of Reference

TOS

Temporarily Out of Service

TP

Toll Plant or Point

TP

Transport Protocol (ISO)

ToS TP TP

Type of Service

Transaction Processing Twisted Pair

TPAU

Twisted Pair Attachment Unit

TPMR

Trunk Private Mobile Radio

TPDU

Transport Protocol Data Unit

Acronyms and Abbreviations in Telecommunications

TPON

Telephony over Passive Optical Network

TR

Token Ring

TQM

Total Quality Management

TR

Toll Restriction

TR VLAN

Token Ring Virtual LAN

TR

Transmit-Receive

TRA

Telecommunications Regulatory Authority (Bahrain)

TRA

Traffic Routing Administration

TRA TRAI

TRAC

TRANSEC TRAPI TRAU TRC TRC TRC

TRE

TRISL TRS

135

Telecommunications Regulatory Authority (Oman) Telecom Regulatory Authority of India

Technical Recommendations Application Committee Transmission Security Transport API

Transcoder and Rate Adaption Unit

Telecommunications Regulatory Commission (Jordan)

Telecommunications Regulatory Commission of Sri Lanka Transverse Redundancy Check

Telecommunications Regulatory Entity (Albania) Token Ring Inter-Switch Link

Telecommunications Relay Services

TRX

Transceiver

TS

Transmission Speed

TSAPI

Telephony Services Applications Programming Interface

TS

TSAP

Traffic Station

Transport Service Access Point

136

Acronyms and Abbreviations in Telecommunications

TSC

Transit Switching Centre

TSI

Time Slot Interchange

TSF TSI

TSK

Telephone Service Factor

Transmitting Subscriber Information Transmission Security Key

TSLRIC

Total Service Long Run Incremental Costs

TSP

Tag-Switched Path

TSM

Time Switch Module

TSP

Telecommunications Service Priority

TSR

Telecommunications Service Request

TSPS TSR

TSRM

Traffic Service Position System

Terminate and Stay Resident

Telecommunication Standards Reference Manual

TSS

Tandem Switching System

TSS

Telecommunications Terminal Equipment

TSS

Telecommunication Standardization Sector (ITU-T)

TT

Dial Repeating Tie Line/Dial Repeating Tie Trunk

TT

Trunk Type

TT TTL TTL TTP

TTPS

TTTEL TRF

TTTN

Touch-Tone Adaptor

Transistor-Transistor Logic Time-to-Live

Trail Termination Point (TMN) Trusted Third-Party Services

Trinidad and Tobago Telecommunications Authority

Tuned Radio Frequency

Tandem Tie Trunk Network

Acronyms and Abbreviations in Telecommunications

TTY

TeleType

TU

Tributary Unit

TTY TUA

TUD

Telecommunications Device for the Deaf Telecommunications Users Association (UK) Trunk Up-Down

TUG

Telecommunication User Group

TUNIP

TCP and UDP over Nonexistent IP

TULIP TUR TVR TW

TCP and UDP over Lightweight IP

Trunk Utilisation Report Teletel Vitesse Rapide

Travelling Wave

TWA

Two-Way Alternate (HDLC)

TWT

Travelling Wave Tube

TWS

TWTA

Two-way Simultaneous (HDLC) Travelling Wave Tube Amplifier

TWX

Teletypewriter

TX

Transmitter

TXE

Telephone Exchange Electronic

TXMTR

Transmitter

TWX TXD TXK TXS

Teletypewriter Exchange (Telex) Telephone Exchange Digital

Telephone Exchange Crossbar

Telephone Exchange Strowger

137

U

138

U/L UA

Acronyms and Abbreviations in Telecommunications

Uplink

Unbalanced Asynchronous (HDLC)

UA

Universal Access

UA

User Agent

UA UAN

UART UAS

UAWG UAX UBR

Unnumbered Acknowledgement (HDLC) User Access Node

Universal Asynchronous Receiver Transmitter

Unavailable Seconds

Universal ADSL Working Group

Unit Automatic Exchange

Unspecified Bit Rate (ATM)

UC

Unified Communications

UCC

Uganda Communications Commission

UCA UCD

UCM UCP

Utility Communications Architecture Uniform Call Distribution Universal Call Model

Universal Computer Protocol

UCS

Universal Communications Standards

UDI

Unrestricted Digital Information (ISDN)

UCSP UDLP UDP UDP

UDSL

Unified Communications Service Provider UniDirectional Link Protocol

User Datagram Protocol

User Datagram Protocol Unidirectional HDSL

Acronyms and Abbreviations in Telecommunications

139

UE

User Equipment

UI

Unnumbered Information (HDLC)

UITS

Unacknowledged Information Transfer Service (ITU-T)

UHF UISG UKAS

UKIUF

UKPOA ULF

Ultra High Frequency

Utility Industry Standards Group

United Kingdom Accreditation Service

UK ISDN User Forum

UK Paging Operators’ Association

Ultra Low Frequency

ULL

Unbundling the Local Loop

UM

Unified Messaging

ULP

Upper-Layer Protocol

Um

GSM Air Interface

UMS

Universal Messaging System

UMB UMTS UN

UNI

UNITE UNMA UP

Upper Memory Block

Universal Mobile Telecommunications System

Unbalanced Normal

User/Network Interface

User Network for Information Exchange on Telecommunications in Europe

Unified Network Management Architecture

Unnumbered Poll

UPC

Usage Parameter Control (ATM)

UPF

UnPlugFests

UPCS UPS

Universal Personal Communications Services Uninterruptable Power Supply

140

Acronyms and Abbreviations in Telecommunications

UPT

Universal Personal Telecommunications

UPTAC

UPT Access Code

UPTAA

UPT Access Address

URL

Uniform Resource Locator

URSEC

Unidad Reguladora de Servicios de Comunicaciones (Uruguay)

URM

URTiP US

USART USAT USB

Usage Reference Model

Office of Telecommunications and Post Regulation (Poland) Universal Service

Universal Synchronous Asynchronous Receiver Transmitter Ultra Small Aperture Terminal

Upper Sideband

USC

Universal Service Contribution

USIM

UMTS Subscriber Identity Module

USIM USO

Universal Subscriber Identity Module

Universal Service Obligation

USOC

Universal Service Order Code

USSD

Unstructured Supplementary Service Data

USP

USTA UT

Universal Service Provider

United States Telephone Association

Universal Time

UTC

Coordinated Universal Time

UTRA

Universal Terrestrial Radio Access

UTP

UTRAN

Unshielded Twisted Pair

Universal Terrestrial Radio Access Network

Acronyms and Abbreviations in Telecommunications

UUI

User-to-User Indentification

uv

Ultraviolet

UVM-C

Universal Voice Module-Channelised

UWB

Ultra-Wideband

UUS UVM

UVM-U

User to User Signalling

Universal Voice Module

Universal Voice Module-Unchannelised

141

V

142

Acronyms and Abbreviations in Telecommunications

V/D

Voice/Data

VA

Value-Added

VADS

Value Added Data Services

V/FoIP VAD

VADSL

Voice and Fax over Internet Protocol

Voice Activity Detection

Very High Speed ADSL (see VDSL)

VAN

Value-Added Network

VAP

Value Added Process

VANS VAR VAS VB

Value Added Network Services

Value-Added Reseller

Value Added Services

Virtual Bandwidth

VBI

Vertical Blanking Intervals

VBR

Variable Bit Rate (ATM)

VBR-RT

Variable Bit Rate-Real-Time (ATM)

VBNS VBR-NRT VC VC VC

VCA

Very High Speed Backbone Network Service Variable Bit Rate-Non-Real-Time (ATM)

Virtual Channel (ATM) Virtual Circuit (PSN)

Virtual Container (SDH)

Voice Connecting Arrangement

VCC

Virtual Calling Card

VCD

Virtual Circuit Descriptor

VCC

Virtual Channel Connection (ATM)

Acronyms and Abbreviations in Telecommunications

VCI

Virtual Channel Identifier

VCL

Virtual Channel Link

VCI

VCS

VDSL VDT

VDU

Virtual Circuit Identifier (ATM) Virtual Circuit Switch

Very High-Speed Digital Subscriber Line

Visual Display Terminal

Visual Display Unit

VF

Variance Factor

VFCT / VFCTG

Voice Frequency Carrier Telegraph

VF

VFDF

Voice Frequency

Voice Frequency Distribution Frame

VFO

Variable-Frequency Oscillator

VG

Voice Grade

VGF

Voice Grade Facility

VFTG VGA VHDSL

Voice-Frequency Telegraph

Video Graphics Adapter Very High Bit Rate Digital Subscriber Line

VHE

Virtual Home Environment

VI

Vector Identifier

VL

Vector Length

VLBR

Very Low Bit Rate

VLI

Virtual LAN Internetwork

VHF VIP

VLAN VLF

Very High Frequency

VINES Internet Protocol

Virtual LAN

Very Low Frequency

143

144

Acronyms and Abbreviations in Telecommunications

VLSI

Very Large Scale Integration

VM

Virtual Machine

VMAC

Virtual Media Access Control

VLSM VM

VMS

VMSC

Variable-Length Subnet Mask

Virtual Memory

Voice Messaging System

Voice Mail System Centre

VNL

Via Net Loss

VNS

Vehicle Navigation System

VNLF VNS

VoATM

Via Net Loss Factor

Virtual Network Service Voice Over ATM

vocoder

Voice-Coder

vodas

Voice-Operated Device Anti-Sing

vogad

Voice-Operated Gain-Adjusting Device

VoIP

Voice over Internet Protocol

VoD

VoFR VoHDLC volcas vox

VP

Video-on-Demand

Voice-over-Frame Relay Voice over HDLC

Voice-Operated Loss Control And Echo/Signalling Suppression Voice-Operated Relay Circuit Virtual Path

VPC

Virtual Path Connection

VPDN

Virtual Private Dial-up Network

VPDN

Virtual Private Data Network

Acronyms and Abbreviations in Telecommunications

VPI

Virtual Path Identifier

VPLMN

Visited Public Land Mobile Netwok

VPL

Virtual Path Link

VPN

Virtual Private Networks

VQA

Voice Quality Assessment

VRC

Vertical Redundancy Check

VRRP

Virtual Router Redundancy Protocol

VPT

VQT

VRML VSA

VSAM VSAT

Village Public Telephone

Voice Quality Testing

Virtual Reality Markup Language

Vector Signal Analyser

Virtual Storage Access Method

Very Small Aperture Terminal

VSB

Vestigial Sideband

VSM

Vestigial Sideband Modulation

VSI

VSWR

Virtual Switch Interface

Voltage Standing Wave Ratio

VT

Virtual Terminal (ISO)

VTAM

Virtual Telecommunications Access Method

VT

VTE

Virtual Tributary

Virtual Terminal Environment

VTOA

Voice and Telephony Over ATM

VTU

Video Teleconferencing Unit

VTP vu

Virtual Terminal Protocol

Unit of Volume

145

W

146

W3C

WAC

WACS

WADS

Acronyms and Abbreviations in Telecommunications

World Wide Web Consortium

Wide Area Communication

Wireless Access Communications System Wide Area Data Service

WAE

Wireless Application Environment

WAN

Wide Area Network

WARC

World Administration Radio Conference

WB/BB

Wide Band/Broadband

WC

Wire Centre

WCS

Wireless Communications Service

WDM

Wavelength Division Multiplex

WAIS WAP

WATS

WBDTS WCDMA W-DCS WDP

Wide Area Information Services Wireless Application Protcol

Wide Area Telecommunications Service

Wide Band Data Transmission Forum

Wideband CDMA

Wideband Digital Crossconnect System Wireless Datagram Protocol

WFQ

Weighted Fair Queuing

WGS

Worldwide Geodesic System

WG

WiFi/WiMAX WIN WIN

Working Group

Broadband wireless data technologies used for interconnecting computer equipment

Wireless In-Building Network

Wireless Intelligent Network

Acronyms and Abbreviations in Telecommunications

Winsock WLAN

Windows Socket API

Wireless Local Area Network

WLL

Wireless Local Loop

WM

Wireless Manager

WLS

WML WP

Wireless Location Services (SignalSoft) Wireless Markup Language

Workpackage

WPBX

Wireless Private Branch Exchange

WRC

World Radiocommunication Conference

WSF

Work Station Function Block

WPT WS

WSP

Wideband Packet Technology

Workstation

Wireless Session Protocol

WT

Wireless Transceiver

WTLS

Wireless Transport Layer Security

WTA

Wireless Telephony Application

WTO

World Trade Organisation

wv

Working Voltage

WWAN

Wireless Wide Area Network

WWW

World Wide Web

WTP

WVDC

WWDSA WWW3

Wireless Transaction Protocol

Working Voltage Direct Current Worldwide Digital System Architecture

World Wide Web Consortium

147

X, Y and Z

148

Acronyms and Abbreviations in Telecommunications

XA

Exchange Access (SMDS)

XC

Cross-Connect

XDF

Extended Distance Feature

X-Bar xcvr

xDSL xfmr

XID

xistor, xstr XMIT

Crossbar Telephone Exchange

Receiver

Generic Term for Digital Subscriber Line

Transformer

Exchange Identification (HDLC) Transistor

Transmit

XML

Extensible Markup Language

XMSN

Transmission

XMS

XMTD XMTR XNS

XOFF XON XPD

XSM r

Extended Memory Specification Transmitted

Transmitter

Xerox Network Systems

Transmitter Off

Transmitter On

Cross Polarisation Decoupling X Session Manage

XT

Crosstalk

Y2K

Year 2000

XTagATM ZBTSI

Extended Tag ATM

Zero Byte Times Slot Interchange

Acronyms and Abbreviations in Telecommunications

ZCS

Zero Code Suppression

ZIP

Zone Improvement Programme (US geographic codes)

ZD

Zero Defects

ZIS

Zone Information Socket

ZLE

Zero Latency Enterprise (Compaq)

ZIT

Zone Information Table

ZNIIS

Central Research Telecommunication Institute - Russia

ZST

Zone Standard Time

Zo

Characteristic Impedance

149

Numerics

150

0TLP

2G

2B1Q

3G

3GPP 3WC 4GL

4B/5B

Acronyms and Abbreviations in Telecommunications

Zero Transmission Level Point

2nd Generation Mobile Services

Two Binary, One Quaternary (ISDN and ADSL standard line code for transmission of two voice and data channels at 64 kbps and one data and signalling channel at 16 kbps) Third Generation Mobile Services

Third Generation Partnership Project

Three Way Calling

Fourth-Generation Language

4-byte/5-byte local fibre channel used for FDDI/ATM

6BONE

Experimental IPv6 Internet network.

10BaseF

10-Mbps baseband specification for Ethernet over fibreoptic cabling

8B/10B

10BaseFB

10BaseFL 10BaseFP 10BaseT 802.x

8-byte/10-byte local fibre channel

10-Mbps baseband Ethernet specification providing synchronous signalling backbone allowing additional segments and repeaters to be connected to a 10BaseF network.

10-Mbps baseband Ethernet specification intended to replace FOIRL

10-Mbps fiber-passive baseband Ethernet specification using fibre-optic cabling

An implementation of the Ethernet IEEE standard on unshielded twisted-pair wiring at 10 megabits per second. Set of IEEE standards for the definition of LAN protocols

Notes

Acronyms and Abbreviations in Telecommunications

151

About InterConnect Communications 152

Acronyms and Abbreviations in Telecommunications

InterConnect Communications is an established and widely respected supplier of consulting services to the telecommunications and wireless industry. Over the years, the company has assisted governments in Europe, the Middle East and Africa to introduce telecommunications sector reform, establish independent regulatory authorities and develop fair and transparent sector legislation.

InterConnect is now a wholly owned subsidiary of Telcordia Technologies. Telcordia is one of the world’s largest providers of operations support systems, network software and consulting and engineering services to the telecommunications industry. Consulting Services InterConnect’s specific consulting activities include assisting Governments and National Regulatory Authorities to: • • •

develop sector policy and electronic communications law establish and develop independent regulatory authorities define and implement specific supporting regulation i.e. – universal service or access policy and mechanisms – licensing and licence awards – interconnection policy and guidelines – tariff policies and associated regulation – numbering policy and management – equipment certification regimes

Acronyms and Abbreviations in Telecommunications

153

InterConnect also provides Governments and Regulators with expert advice on Radio Spectrum Management and Monitoring. This is an increasingly important activity and InterConnect has considerable practical experience in: • • • • •

development and implementation of radio spectrum policies development of national radio frequency plans, the planning of spectrum usage, and the assignment of frequencies to different users design, specification, procurement, installation and commissioning of spectrum management and monitoring systems creation of spectrum re-farming plans creation of operational systems and processes and institutional development

Specific activities to assist network operators and other organisations include: • • • • • • • •

assistance with the regulatory, commercial and technical aspects of network interconnection and local loop unbundling tariff setting for retail and wholesale business cost base analysis and control the provision of software models i.e. cost allocation network planning, design and build the application and implications of international, regional and national laws and regulations business planning and strategy commercial and technical due diligence

154

Acronyms and Abbreviations in Telecommunications

Training Services InterConnect provides both off-the-shelf and tailored training courses on regulatory, commercial and technical aspects of electronic communications.

In particular, InterConnect provides a highly successful range of courses for industry professionals under the TRMC brand. Since the first TRMC course ran in 2000, ongoing delegate demand has resulted in a steady increase in the number of courses scheduled each year and has also prompted the introduction of new courses on specific regulatory topics to meet delegate requirements.

Report Services InterConnect has a long tradition of producing industry standard reports and publications across a number of topics. The company also provides customers with independently researched and authored analysis to meet their specific requirements. Quality Assurance InterConnect undertakes all work in accordance with its ISO certified quality system.

Contact Us If you would like to discuss how InterConnect can assist you meet your objectives, please email us on [email protected] or by telephone on +44 (1291) 638400. More company information is available on our website www.icc-uk.com.

For more details on the full TRMC range of courses, please visit www.trmconline.com or email [email protected].