# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

#

1-ESS	x-ESS series of "Electronic Switching Systems" from AT&T/Lucent
3G	Third Generation (Mobile Network)
3GPP	Third-Generation Partnership Project
3WC	Three Way calling
4GL	Fourth-Generation Language
800 or 888	Freephone
802.x	Series of LAN standards developed by IEEE
911	Emergency telephone number in North America

# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 

A

AAV	Alternative Access Vendor
ABR	Available Bit Rate
AC	Access Control, or Alternating Current, or Authentication Center (also AUC)
ACD	Automatic Call Distributor
ACE	Authentication Encryption
ACEK	Authentication Encryption Key
ACK	Acknowledgement
ACP	Access Control Point
ACRE	Authorization and Call Routing Equipment
ADM	Add-Drop Multiplexer (SDH Element)
ADPCM	Adaptive Differential Pulse Code Modulation
ADSL	Asymmetric Digital Subscriber Line
AGRAS	Air-Ground Radiotelephone Automated Service
AIOD	Automatic Identification of Outward Dialed calls
AIN	Advanced Intelligent Network (ANSI IN Standard)
A-key	Authentication key
ALI	Automatic Location Information
AM	Amplitude Modulation
AMPS	Advanced Mobile Phone System
ANI	Automatic Number Identification
ANS	Advanced Network Services
ANSI	American National Standards Institute
ANSI-41	ANSI standard for mobile management (ANSI/TIA/EIA-41)
ANT	ADSL Network Terminator
AOA	Angle of Arrival
AOL	America On Line (ISP)
API	Application Programming Interface
APPC	Advanced Program-to Program Communications (IBM SNA)
APPN	Advanced Peer-to-Peer Network (IBM SNA)
ARCnet	Attached Resource Computer Network (Datapoint)
ARDIS	Advanced Radio Data Information Service
ARP	Address Resolution Protocol
ARPA	Advanced Research Projects Agency
ARPU	Average Revenue Per User
ARPANET	ARPA Network
ARQ	Automatic Repeat Request
ARS	Automatic Route Selection
ASCII	American Standard Code for Information Interchange
ASIC	Application-Specific Integrated Circuit
ASN.1	Abstract Syntax Notation 1 (ISO)
ASP	Application Service Provider
ASR	Automatic Send Receive, Automatic Speech Recognition
AT&T	American Telephone & Telegraph
ATIS	Alliance for Telecommunications Industry Solutions (formerly ECSA)
ATM	Asynchronous Transfer Mode, Automatic Teller Machine
ATSC	Advanced Television Systems Committee
AUI	Attachment Unit Interface
AWG	American Wire Gauge
AXE 10	Series of electronic telephone exchanges from L.M. Ericsson

# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 

B

B2B	Business-to-Business
B2C	Business-to-Consumer
B8ZS	Binary Eight Zero Substitution
BACP	Bandwidth Allocation Control Protocol
BBS	Bulletin Board System
Bellcore	Bell Communications Research, Inc. (Now Telcordia)
BEP	Back-End Processor
BER	Bit Error Rate
BERT	Bit Error Rate Test (or Tester)
BIOS	Basic Input-Output System
B-ISDN	Broadband ISDN
BOC	Bell Operating Company (USA)
BONDING	Bandwidth On Demand Interoperability Group
bps	bits per second
BRI	Basic Rate Interface (ISDN)
BS	Base Station
BSC	Base Station Controller, or Binary Synchronous Communications (IBM)
BSS	Base Station Sub-system (GSM)
BSS	Business Support Systems
BTS	Base Transceiver Station

# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 

C

CAD	Computer-Aided Design
CAM	Computer-Aided Manufacturing
CAMEL	Customized Applications for Mobile-network Enhanced Logic (GSM/ETSI)
CAN	Campus Area Network
CANARIE	Canadian Network for Advancement of Research, Industry, Education
CAP	Competitive Access Provider
CAPS	Common ISDN API Service
CARS	Cable Antenna Relay Services
CASE	Computer-Aided Software Engineering
CATV	Cable Television or Community Antenna Television
CAVE	Cellular Authentication and Voice Encryption
CB	Citizens Band
CBR	Constant Bit Rate
CCC	Clear Channel Capability
CCCH	Common Control Channel
CCD	Charge Coupled Device
CCIR	Comité Consultatif International des Radiocommunications (now ITU-R)
CCITT	Comité Consultatif International des Télégraphes et Téléphones (now ITU-T)
CCR	Customer Controlled Reconfiguration
CCS	Common Channel Signaling
CCSS6	Common Channel Signaling System # 6
CD-R	Compact Disk-Recordable
CD-ROM	Compact Disk-Read-Only Memory
CDMA	Code Division Multiple Access
CDO	Community Dial Office
CDPD	Cellular Digital Packet Data
CDR	Call Detail Record
CENTREX	Central Office Exchange (PBX-like Service)
CEPT	Conference of European Posts and Telecommunications
CERN	Centre Européen de Recherche Nucléaire
CGSA	Cellular Geographic Service Areas
CIR	Committed Information Rate
CLASS	Custom Local Area Signaling Services
CLEC	Competitive Local Exchange Carrier
CLI	Calling Line Identification
CMA	Communications Management Association
CMIP	Common Management Information Protocol (ISO)
CMIS	Common Management Information Services (ISO)
CMISE	Common Management Information Service Element (ISO)
CMOS	Complementary Metal Oxide Semiconductors
CMRS	Commercial Mobile Radio Service
CNET	Centre National d'Études en Télécommunications (France Telecom)
CNI	Calling Number Identification
CO	Central Office
Codec	Coder/decoder
CON	Concentrator
COO	Cell of Origin
CORBA	Common Object Request Broker Architecture (OMG)
COT	Central Office Terminal
cPCI	Compact Peripheral Component Interconnect
CPE	Customer Premises Equipment
CPN	Cisco Powered Network (Ingredient Band)
CPP	Calling Party Pay
CPS	Cycles per second (Hertz)
CPU	Central Processing Unit
CRC	Cyclic Redundancy Check
CRM	Customer Relationship Management
CSA	Carrier Servicing Area
CSM	Communications Services Management
CSMA/CD	Carrier Sense Multiple Access with Collision Detection
CSR	Customer Service Representative
CSU	Channel Service Unit
CT	Cordless Telecommunications
CTI	Computer Telephony Integration
CTIA	Cellular Telecommunications Industry Association
Cu	Copper Local Loop
CUG	Closed User Groups

# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 

D

D-AMPS	Digital Advanced Mobile Phone Service
DA	Destination Address
DAP	Demand Access Protocol
DARPA	Defense Advanced Research Projects Agency
DAT	Digital Audio Tape
dB	deciBel
DBMS	Database Management System
DBS	Direct Broadcast Satellite
DCE	Data Communications Equipment, or Distributed Computing Environment
DCU	Distribution and Control Unit
DDD	Direct Distance Dialing
DDS	Dataphone Digital Service
DECT	Digital Enhanced (formerly, European) Cordless Telecommunication
DES	Data Encryption Standard
DLCS	Digital Loop Carrier System
DLL	Dynamic Link Library
DLU	Digital Line Unit
DM	Distributed Management
DME	Distributed Management Environment (OSF)
DMI	Distributed Management Interface
DMS	Digital Multiplex Switch (Nortel Networks Switching Product Family DMS 100, 200, …)
DMT	Discrete Multitone
DMTF	Desktop Management Task Force
DNA	Digital Network Architecture (Digital Equipment Corporation)
DNS	Domain Name Service DoD Department of Defense (USA)
DOS	Disk Operating System
DOV	Data Over Voice
DPCM	Differential Pulse Code Modulator
DS	Digital Service, Digital Signal
DS-0	Digital Signal, Level 0 (64 kbps)
DS-1	Digital Signal, Level 1 (1.544 Mbps)
DS-1C	Digital Signal, Level 1C (3.152 Mbps)
DS-2	Digital Signal, Level 2 (6.312 Mbps)
DS-3	Digital Signal, Level 3 (44.736 Mbps)
DS-4	Digital Signal, Level 4 (274.176 Mbps)
DSI	Digital Speech Interpolation
DSL	Digital Subscriber Line
DSP	Digital Signal Processor
DSS	Decision Support System
DSU	Digital Service Unit
DTAM	Document Transfer and Manipulation (ISO)
DTE	Data Terminal Equipment
DTMF	Dual-Tone MultiFrequency
DTU	Data Transfer Unit
DTV	Digital Television
DVB	Digital Video Broadcasting
DWDM	Dense Wavelength Division Multiplexing
DXI	Data Exchange Interface

# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 

E

E2E	End-to-End
E-911	Enhanced emergency telephone number (USA)
E&M	Ear and Mouth, or recEive and transMit (signaling)
E-TDMA	Expanded Time Division Multiple Access
EAI	Enterprise Application Integration
EBCDIC	Extended Binary Coded Decimal Interchange Code (IBM)
EC	European Community
ECMA	European Community Manufacturers Association
ECSA	Exchange Carrier Standards Association (now ATIS)
EDGE	Enhanced Data for GSM Evolution
EDI	Electronic Data Interchange
EEROM	Electronically Erasable Read-Only Memory
EF&I	Engineering, Furnishing and Installation
EFT	Electronic Funds Transfer
EHF	Extremely High Frequency (more than 30 GHz)
EIA	Electronic Industries Association
EIR	Equipment Identity Register
EISA	Extended Industry Standard Architecture
EMEA	Europe, Middle East & Africa (Business Region)
EML/EMS	Element Management Layer/ Element Management Service
EMS	Enhanced Messaging Services
ENS	Enhanced Network Services
EOT	End of Transmission
EPI	External Provisioning Interface
ERMES	European Radio Message System (standard for pagers)
ERP	Enterprise Resource Management
ESCON	Enterprise System Connection (IBM)
ESMR	Enhanced Specialized Mobile Radio
ETSI	European Telecommunications Standard Institute
EU	European Union

# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 

F

FASB	Financial Accounting Standards Board (USA)
FAT	File Allocation Table
FC	Frame Control, or Fiber Channel
FCAPS	Fault, Configuration, Accounts, Performance, Security (ISO)
FCC	Federal Communications Commission (USA)
FCS	Frame Check Sequence
FDD	Frequency Division Duplex
FDDI	Fiber Distributed Data Interface
FDIC	Federal Deposit Insurance Corporation (USA)
FDMMA	Frequency Division Multiplexing Multiple Access
FEP	Front-End Processor
FHSS	Frequency Hopping Spread Spectrum
FIFO	First-In First-Out
FITL	Fiber In The Loop
FM	Frequency Modulation
FMS	Fraud Management System
FO	Fiber Optic
FOD	Fax on Demand
FR	Frame Relay
FRAD	Frame Relay Access Device, or Assembler/ Disassembler
FRS	Family Radio Service
FSK	Frequency-Shift Keying
FSS	Fixed Satellite System
FTAM	File Transfer, Access, and Manipulation (ISO)
FT1	Fractional T1
FTP	File Transfer Protocol (TCP/IP)
FTS	Federal Telecommunications System
FTTB	Fiber To The Building
FTTC	Fiber To The Curb
FTTK	Fibre To The Kerb
FTTH	Fiber To The Home
FWA	Fixed Wireless Access

# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 

G

GAN	Global Area Network
GATT	General Agreement on Tariffs and Trade
Gb	gigabit
GB	gigabyte
GDS	Generic Digital Services
GEO	Geostationary-Earth-Orbit
GHz	gigaHertz (billions of cycles per second)
GIS	Geographic Information System
GMRS	General Mobile Radio Service
GOSIP	Government Open Systems Interconnection Profile (USA)
GPRS	General Packet Radio Service
GPS	Global Positioning System
GRX	GPRS Roaming Exchange
GSA	General Services Administration (USA)
GSM	Global System for Mobile telecommunications, or Groupe Spécial Mobile
GUI	Graphical User Interface
GVPN	Global Virtual Private Network

# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 

H

H0	High-capacity ISDN channel operating at 384 kbps
H11	High-capacity ISDN channel operating at 1.536 Mbps
H323	ANSI standard for format over IP
HDLC	High-level Data Link Control (ISO)
HDSL	High-bit-rate Digital Subscriber Line
HDTV	High-Definition Television
HF	High Frequency (3 MHz to 30 MHz)
HFC	Hybrid Fiber/Coax
HIC	Head-end Interface Converter
HLR	Home Location Register
HomePNA	Home Phoneline Networking Alliance
HPPI	High-Performance Parallel Interface
HTML	HyperText Markup Language
HTTP	HyperText Transfer Protocol
HVAC	Heating, Ventilation, and Air Conditioning
Hz	Hertz (cycles per second)

# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 

I

I/O	Input/Output
IA5	International Alpha Set No. 5
IAB	Internet Architecture Board
IAC	Install And Commission
IANA	Internet Assigned Numbers Authority
ICANN	Internet Corporation for Assigned Names and Numbers
ICI	Interexchange Carrier Interface
ICMP	Internet Control Message Protocol
ICR	Intelligent Call Routing
ICS	Intelligent Calling System ID Identification
IDDD	International Direct Dialing Designator
iDEN	integrated Dispatch Enhanced Network
IDPR	Interdomain Policy Routing
IEC	International Electrotechnical Commission, or InterExchange Carrier
IEEE	Institute of Electrical and Electronics Engineers
IESG	Internet Engineering Steering Group
IETF	Internet Engineering Task Force
ILEC	Incumbent Local Exchange Carrier
IM	Instant Messaging
IMAP	Internet Mail Access Protocol (IETF)
IMEI	International Mobile Equipment Identity
IMN	Intelligent Mobile Network
IMT-2000	International Mobile Telecommunications 2000 (ITU)
IMSI	International Mobile Subscriber Identity
IN	Intelligent Network
IN7	Compaq SS7 stack (previously DECss7)
INAP	Intelligent Network Application Part (IN)
INMS	Integrated Network Management System
INTELSAT	International Telecommunications Satellite Organization