1-1SDoC	One Standard-One Test, Supplier's Declaration of Conformity
2B1Q	2 Binary 1 Quaternary (U.S. line coding for ISDN
2D-VLC	Two Dimensional Variable Length Coding
3G	Third Generation
3GPP	Third Generation Partnership Project (ETSI)
3WC	Three Way Call
4B3T	4 binary 3 trinary (European line coding for ISDN)
10MDSL	10 Mbit/s DSL
-A-
A/D	Analog to Digital
A&T	Architecture & Transport (DSL Forum Committee, formerly ATM)
A/TT	Analog Tie Trunk (TIA-646-B)
AAA	Authentication, Authorization and Accounting
AAC	Advanced Audio Coding
AACCH	Auxiliary Analog Control Channel
AAL	ATM Adaptation Layer
AAL(D)	Analog PSTN Access Line (Analog PBX Interface, TIA-646-B)
AAL5-CU	ATM Adaptation Layer 5 Composite User
AAP	Alternative Approval Procedures (ITU)
AASO	Advanced Audio Server Override (package)
AASB	Advanced Audio Server Base
AASS	Advanced Audio Server Set (package)
AAU	Advanced Audio Package
AAV	Authentication Algorithm Version
ABAC	Aggregate Bearer Admission Control
AbC	Approval by Correspondence
ABM	Aggregate Bearer Measurement
ABNF	Augmented Backus-Naur Form
ABR	Average Bit Rate
ABT	Adaptive Block Transform
AC	Advisory Circular
ac	alternating current
AC	Alternating Current
AC	Arithmetic Coding
AC	Authentication Center
AC	Auto Configuration (DSL Forum)
AC	Automatic Callback
ACA	Adaptive Channel Allocation
ACBO	Automatic Cross Band Operation
ACC	Analog Control Channel
ACC	Automatic Configuration Client
ACC	Automatic Congestion Control
ACCH	Associated Control Channel
ACD	Automatic Call Distribution
ACE	Advanced Coding Efficiency
ACELP	Adaptive CELP
ACF	Admission Confirm
ACF	Authentication Control Function
ACG	Automatic Code Gapping
ACI	Anonymous Call Interception
ACIL	Association of Independent Scientific, Engineering and Testing Firms
ACK	Acknowledgment
ACKS	Acknowledgments
ACM	Address Complete Message
ACOS	IEC Advisory Committee on Safety
ACR	Absolute Category Rating
ACR	Alternate Carrier Routing
ACR	Anonymous Call Rejection
ACRE	Authorization and Call Routing Equipment
ACS	Auto-Configuration Server
ACS	Automatic Configuration Service
ACSB	Amplitude Companded Single Side Band
ACSE	Association Control Service Element
ACT	Activation
ACTA	Administrative Council for Terminal Attachment (T1 and TIA)
ACTE	Approvals Committee for Terminal Equipment
ACTS	Advanced Communications Technology Satellite
AD	Administrative Domain
ADA	Americans with Disabilities Act
ADAAG	ADA Accessibility Guidelines
AD-BES	Administrative Back-End Services
ADC	Analog to Digital Converter
ADDS	Application Data Delivery Service
ADHAG	Ad Hoc Authentication Group (TR-45.2)
ADI	Analog Devices Inc.
ADL	All Digital Loop (without underlying POTS or ISDN)
ADL	Automatic Determination of Location
ADLC	Asynchronous Data Link Control
ADLG	Automatic Determination of Location and Guidance
ADLNB	Association of Designated Laboratories and Notified Bodies (European)
ADLU	All Digital Loop masks
ADM	All Digital Mode
ADP	Answer Detection Pattern
ADPCM	Adaptive Differential PCM
ADS	Asynchronous Data
ADSI	Analog Display Services Interface (Bellcore)
ADSL	Asymmetric Digital Subscriber Loop (Line)
ADSLF	ADSL Forum
ADSL-R	Asymmetric Digital Subscriber Loop (Remote)
ADT	Asynchronous Data Teleservice
AEC	Acoustic Echo Controller
AECE	Acoustic Echo Control Equipment
AES	Advanced Encryption Standard-Rijndael
AFE	Analog Front End
AFNOR	Association francaise de normalisation (French Standardization)
AG	Access Grant
AGC	Audiographics Conferencing
AGC	Automatic Gain Control
AGCH	Access Grant Channel
AGNI	Advisory Group for Network Issues
AHAG	Ad Hoc Authentication Group (TR-45)
AHES	Ad Hoc Emergency Services (TR-45.2)
AHG	Ad Hoc Group
aHIT!	TIPIA merger into IMTC
AHMMG	Ad Hoc Microcell/Microsystems Guidelines
AHPAI	Ad Hoc PCS Air Interface Joint Group
AHSOG	Ad Hoc on Self Organization Group
AHWG	Ad Hoc Working Group
AI	Air Interface
AI	Answer Indicator (V.8)
AIC	Advanced Intra Coding
AIG	Administrators Interest Group
AIG	Authentication Implementation Guide
AIIM	Association for Information and Image Management
AIM	Audio in Multimedia (EBU Project Group B)
AIN	Advanced Intelligent Network
AINI	ATM Inter Network Interface
AIS	Alarm Indication Signal
AIV	Alternative Inter VLC
a.k.a.	Also Known As
AKA	Authentication and Key Agreement
AL	Answer List
AL1	H.223 Adaption Layer 1
AL-PDU	Answer List - Protocol Data Unit
AL-SDU	Answer List - Service Data Unit
ALC	Automatic Level Control
ALCE	Automatic Level Control Equipment
ALE	Automatic Link Establishment Radios
ALF	Application Level Framing
ALI	Automatic Location Identification
ALIT	Automatic Line Insulation Test
ALT	Automatic Link Transfer
ALU	Arithmetic Logic Unit
AM	Amplitude Modulation
AM	Assignment Message
AMA	Adaptive Motion Accuracy
AMA/CDR	Automatic Message Accounting/Call Detail Recording
AMD	Amendment
AMF	Authentication Management Function
AMPS	Advanced Mobile Phone Service
AMR	Adaptive MultiRate
AMR-WB	Adaptive Multi-Rate Wideband
AN	Access Network
AN	Access Node
AN	Advisory Note
ANAI	Access Network Architecture and Interfaces
ANATEL	Agencia Nacional de Telecomunicacoes (Brazil)
ANF	Additional Network Feature
ANF-CMN	Additional Network Feature - Common Information (H.450.12)
ANFP	Access Network Frequency Plan
ANI	Automatic Number Identification
ANOVA	Analysis of Variance Procedure
ANS	Answer Tone
ANSam	Answer Tone, amplitude modulated (V.8)
ANSI	American National Standards Institute
ANT	Access Network Transport (Q1/15)
AOC	Advice of Change
AOC	Advice of Charge
AOC	ADSL Overhead Channel
AOC-D	Advice Of Charge during a call
AOC-E	Advice Of Charge at the End of a call
AOD	Audio on Demand
AOL	America On Line (Commercial service)
AP	Advanced Prediction
AP	Application Protocols
APCM	Analog PCM Modem
APCO	Associated Public Safety Communications Officers, Inc.
APD	Photodiode with Avalanche gain
APDU	Application Protocol Data Unit
APE	Application Protocols Entities
APEC	Asian Pacific Economic Cooperation
API	Application Programming Interface
APIC	APCO Project 25 Interface Committee
APLAC	Asian Pacific Laboratory Accreditation Cooperation
APON	ATM PON
APP	Application Marker
APS	Asynchronous Protocol Specification
AR	Adaptive Reception Control
AR	Auto-Regressive
AR	Automatic Recall
ARC	Adaptive Reception Control
ARC	Alarm Reporting Control
ARCH	Access Response Channel
ARDB	Administrative Reference DataBase
ARF	Audio Resource Function
ARIB	Association of Radio Industries and Businesses (accredited standards setting body in Japan)
ARJ	Admission Reject
ARLP	Acoustic Reference Level Plan
ARM	Application Resource Manager
ARQ	Admission Request (H.225)
ARQ	Automatic Repeat Request
arTISIL	active and recent Testing & Interoperability WG and Interoperability Sub-Working Group Series/Items Logs
ASAP	As Soon As Possible
ASC	Automatic Service Configuration
ASCII	American Standard Code for Information Interchange
ASE	Applications Service Element
ASIC	Application Specific Integrated Circuit
ASID	Access, Searching and Indexing of Directories
ASL	Active Speech Level
ASN	Abstract Symbol Notation
ASO	Arbitrary Slice Ordering
ASOG	Access Service Ordering Guidelines
ASON	Automatic Switched Optical Networks (IETF)
ASP	Advanced Simple Profile
ASP	Application Service Provider
ASR	Automatic Speech Recognition
ASTM	formerly American Society of Testing and Measurement
ASVD	Analog SVD
AT	Access and Terminals (ETSI TC)
AT	Asynchronous Terminal
ATA	Analog Terminal and Access Project
ATa	Analog Working Group (ETSI TC AT)
AT-A	ETSI Access and Terminals Analog Working Group
ATAAB	Analog Technical Ad hoc Advisory Board
ATAc	ATA's Conventional Technology WG
ATAe	ATA's Enhanced Technology WG
ATBCB	Architectural and Transportation Barriers Compliance Board
ATC	Analog Traffic Channel
AT-D	Access and Terminals Digital Working Group (ETSI)
ATd	Digital Working Group (TC AT)
ATf	Features Working Group (TC AT)
ATF	Administrative Task Force
AT-F	ETSI Access and Terminals Features Working Group
ATG	Access Transport Group (DSL Forum)
ATIA	Australian Telecommunications Industry Association
ATIS	Alliance for Telecommunications Industry Solutions
ATM	Asynchronous Transfer Mode
ATMB-PON	Asynchronous Transfer Mode Broadband Passive Optical Network
ATMF	ATM Forum
ATMOVE	Adaptive-Template Movement
ATM	Asynchronous Transfer Mode - Transmission Convergence
ATM-Utopia	Universal Test and Operations Physical Layer Interface for ATM
ATO	Analog Tandem Office (TIA-646-B)
ATS	Abstract Test Suite
ATS	Assigned Time Slot
ATSC-DASE	Advanced Television Systems Committee - DTV Application Software Environment
ATU-C	ADSL Transceiver Unit - Central Office End
ATU-R	ADSL Transceiver Unit - Remote Terminal End
ATV	Advanced Television
A-UA	Authentication User
AuC	Authentication Center
AuF	Authentication Function
AV	AudioVisual
AVC	Audio Visual Coding
AVC	Audiovisual Conferencing
AVD	Alternating Voice Data
AVI	Interactive Audiovisual Services
AVIS	Audio Visual Information Systems
AVMMS	AudioVisual and MultiMedia Services
AVT	Audio/Visual Transport
AWG	American Wire Gauge
AWG	Arbitrary Wave Form Generator (TR-30.3)
AWGN	Additive White Gaussian Noise
AWI	Alert With Info
-B-
B	Bi-directionally predicted
B2B	Business-to-Business
B2C	Business-to-Consumer
B2G	Business-to-Government
B&G	Bits&Gains (Q4/15)
B&W	Black and White
BA	Basic Access (ISDN)
BAM	Biconic Connector
BAPT	Bundesamt fur Post und Telekommunikation
BARAS	ETSI SAGE standard encryption algorithm for audiovisual services
BAS	Bit rate Allocation Signal
BAU	Base Audio Package
BB	Bandwidth Broker
BBN	Bulk Billing Number
BB-RAS	Broadband Remote Access Server
BBS	Bulletin Board System
BC	Basic Call
BC	Bearer Channel
BCC	Basic Control Channel
BCCA	Board Committee on Conformity Assessment
BCCH	Broadcast Control Channel
BCD	Binary Coded Decimal
BCD	Broadband Content Delivery
BCDF	Broadband Content Delivery Forum
BCF	Backward Control Field
BCF	Bearer Control Function
BCH	Bose, Chaudhuri, and Hocquengham
BCM	Back Channel Message
BCTP	Basic Call Transfer Protocol (SG11)
BD	Bjøntegaard Delta
BDBRS	Bjøntegaard Delta Bit Rate Savings
BD-PSNR	Bjøntegaard Delta PSNR
BDS	Blank Detail Specification
BE	Border Element
BEM	Big Emerging Markets
BER	Bit Error Rate
BERT	Bit Error Rate Test
BES	Back-End Services
BEST	Back-End Service Transaction
(B)FER	Burst Frame Error Rate
BF	Bearer Function
BFI	Bad Frame Indicator
BFOC	Bayonet Fiber Optic Connector
BFT	Binary File Transfer
BGN	Background Noise Conditions
BGP	Border Gateway Protocol (IETF)
B-HLI	Broadband High Layer Information
BICC	Bearer Independent Call Control (ITU-T SG11)
BICSI	Building Industry Consulting Services International
BID	Billing ID Numbers
BINTERMS	Basic Interoperability for Terminals for Telematic Services
B-ISDN	Broadband ISDN
BISS	Basic Interoperable Scrambling System (EBU)
BISS-E	Encrypted Basic Interoperable Scrambling System (EBU)
B-ISUP	Broadband ISDN User Part
BITB	Boulder Industry Test Bed
BLER	Block Error Rates
BLERf	Error Free Block Rate
BLES	Broadband Loop Emulation Service
B-LLI	Broadband Lower Layer Information
BME	Block based Motion Estimation
BMI	Base Station, Mobile Switching Center, and Interworking Function
BMM	Broadcast-Based Multimedia
BMSC	Base Station Manufacturer Code
BNC ID	Backbone Network Connection Identifier
BNF	Backus-Naur Form
B-NT	Broadband Network Termination
BNT	Binary File Transfer
BNTF	Bi-National Task Force
BNTG	Bi-National Task Group
BNWG	Bi-National Working Group
BO	Business Office
BOF	Birds of a Feather
BoD	Board of Directors (DSL Forum)
BOMA	Building Owners & Managers Association
BONDING	Bandwidth On Demand Interest Group (TR-41)
BOS	Business Object Summit
BP	Boundary Point (Q14/9, MediaHomeNet)
BPI+	Baseline Privacy Interface Plus
B-PISN	Broadband PISN
B-PON	Broadband Passive Optical Network
BPTC	Block-Product-Turbo-Codes
B-QSIG	Broadband QSIG
BRA	Basic Rate Access
BRAN	Broadband Radio Access Networks (ETSI TC)
BRAS	Broadband Remote Access Server
BRI	Basic Rate Interface
BRKACK	Break Acknowledge frame (V.42)
BRM	Bit Repetition Message
BRQ	Bandwidth Request
BS	Base Station
BS	Broadcasting Service (Sound) (ITU-R Recommendations)
BSC	Base Station Controller
BSC	Binary Symmetric Channels
BSD	Berkeley Software Design (Unix Operating System)
BSMAP	Base Station Management Application Part
BSMC	Base Station Manufacturer Code
BSMI	Bureau of Standards, Metrology and Inspection
B-SMS	Broadcasts Short Message Service
BSN	Broadband Service Node (Nortel)
BSR	Board of Standards Review (ANSI)
BSS	Base Station System
BSS	Broadcasting-Satellite Service
BST	Broadcast SMS Teleservice
BT	British Telecom (United Kingdom PTT)
BT	Broadcasting Service (Television) (ITU-R Recommendations)
BTA	Basic Trading Area
BTC	Business Telecommunications Committee (ETSI)
BTM	Basic Transfer Mode
BTS	Base Transceiver System
B-UNI	Broadband User Network Interface
B-VOP	Bidirectional Video Object Planes
B/W	Black and White
BWC	Bandwidth Control
BWS	Building Wiring Standard
-C-
C&I	Commands and Indications
C&S	Control and Signaling (ATM Forum Working Group)
CA	Channel Aggregation
CA	Communication Application (T.611)
CA	Conformity Assessment
CAB	Conformity Assessment Body
CABA	Continental Automated Buildings Association (North America's Home and Building Automation Association)
CABAC	Context-based Adaptive Binary Arithmetic Coding
CAC	Carrier Access Code
CAC	Connection Admission Control
CAD	Computer Aided Design
CAGJES	Canadian Advisory Group on Joint Electrical Safety Committee
CAI	Common Air Interface
CAL	Common Application Language
CALEA	Communications Assistance for Law Enforcement Act
CAMA	Centralized Automatic Message Accounting
CANACINTRA	Camara Nacional de la Industria de Transformacion (Mexico)
CANIECE	Camara Nacional de la Industria Electronica Y de Communicaciones Electricas (Mexico)
CAP	Carrier-less Amplitude modulation Phase modulation
CAPI	Common API (ISDN)
CAPCS	Cellular Auxiliary Personal Communications Service
CARE	Carrier Access Records Exchange
CAS	Channel Associated Signaling
CAS	Customer Alert Signal
CASCO	Committee on Conformity Assessment (ISO)
CASE	Conformity Assessment System Evaluation (NIST)
CASS	Common Air Satellite Structure
CAT	Cellular Action Team (ECSP committee)
CATS	Consortium for Audiographics Teleconferencing Standards
CATV	Cable Television
CAVE	Cellular Authentication and Voice Encryption Algorithm
CAWG	Conformity Assessment Working Group (Trilateral)
CB	Call Barring (TIA TR-34)
CB	Certification Body
CB	Citizen Band
CBC	Call Bearer Control
CBC	Cipher Block Chaining
CBEMA	Computing Business Equipment Manufacturers Association (see ITI)
CBP	Coded Block Pattern (H.261)
CBPCM	Coded Block Pattern - Chrominance
CBPC	Coded Block Pattern for Chrominance
CBPY	Coded Block Pattern for Luminance
CBR	Constant Bit Rate
CC	Call Control
CC	Common Carrier
CC	Communication Capability field
CC	Conference Call
CC	Continuity Check (Rec. I.610)
CC	Control Channel
CCA	Common Cryptographic Algorithm
CCAT	CDMA Card Application Kit
CCB	Common Carrier Bureau
CCBS	Completion of Calls to Busy Subscribers
CCI	Connection Control Interface
CCIR	Comite consultatif international des radiocommunications
CCITT	Comite consultatif international telegraphique et telephonique
CCM	Call Connection Management
CCM	Client Connection Manager
CCNR	Completion of Calls on No Reply
CCR	Call Connect Reliability
CCR	Comparison Category Rating
CCS	Common Channel Signaling
CCSN	Common Channel Signaling Network
CCSRL	Control Channel Segmentation and Reassembly Layer
CCT	Channel Check Test
CCT	Consultative Committee - Telecommunications (Trilateral)
CD	Committee Draft
CD	Communication Device
CD	Compact Disk
CD-ROM	Compact Disk-Read Only Memory
CDCP	Call Detail Collect Point
CDF	Cumulative Distribution Function
CDG	CDMA Development Group
CDGP	Call Detail Generation Point
CDH	Cooperative Document Handling
CDIS	Call Detail Information Source
CDL	Coded Digital control channel Locator
CDMA	Code Division Multiple Access
CDN	Content Distribution Network
CDPD	Cellular Digital Packet Data
CDR	Call Detail Recording
CDRP	Call Detail Rating Point
CDS	Caller Display Signaling
CDTAC	FCC Consumer/Disability Telecommunications Advisory Committee
CDV	Committee Draft for Vote, IEC
CE	Capabilities Exchange
CE	Core Experiment
CEA	Consumer Electronics Association
CEASD	Common ETSI Approach to Standards Development
CeBIT	Trade show in Hannover, Germany
CEBus	Consumer Electronics Bus
CEC	Canadian Electric Code
CEC	European Committee for Standardization
CED	Called Station Identification (T.30)
CEG	Card Expert Group (ETSI)
CEG	Integrated Circuit Card Expert Group
CELP	Code Excited Linear Prediction
CEN	Commission Europeenne de Normalisation (European Standards Committee)
CENELEC	Commission Europeenne de Normalisation Electrotechnique (European Electrotechnical Standards Committee)
CEOC	Clear Embedded Operations Channel
CEPT	Conference of European PTTs
CER	Cell Error Ratio
CES	Circuit Emulation Service
CESID	Caller Emergency Station Identification
CEXT	Central Office End Crosstalk
CF	Call Forwarding
CF	Center Frequencies
CF	Communication Functions
CFA	Carrier Failure Alarms (s)
CFBL	Call Forward Busy Line/ Don't Answer
CFI	Calling Feature Indicator
CfP	Call for Proposal
CFP	Computer Fax Protocol
CFP	Cypher Feedback
CFR	Code of Federal Regulations
CFR	Confirmation to Receive
CFU	Call Forwarding - Unconditional
CG	Correspondence Group
CGI	Control Grid Interpolation
CH	Compare HDLC
CHAP	Challenge Handshake Authentication Protocol
CHASE	A class of algorithms for decoding block codes, after D. Chase
CHS	Candidate Harmonized Standard
CI	Call Indicator (V.8)
CI	Calling Identity
CI	Characteristic Impedance
CI	Count Indicator
CI	Customer Installation
CI	Customer Interface
C/I	Carrier to Interference Ratio
CIA	Calling subscriber Internet Address
CIAJ	Communications Industry Association of Japan
CIB	Configuration Information Base
CIC	Circuit Identifier Code
CICES	Canadian Interference Causing Equipment Standard
CICG	Centre International de Conferences Geneve (building used by ITU)
CID	Caller Identification
CIDCW	Calling Identity Delivery on Call Waiting
CIDR	Classless Inter-Doman Routing
CIELAB	a device-independent color space
CIF	Common Intermediate Format
CIG	Calling Subscriber Identification
CILC	Canadian Interconnection Liaison Committee
CIM	Common Information Model
CIP	Component-Independent Palette
CIR	Carrier to Interference Ratio
CISC	CRTC Interconnection Steering Committee
CISPR	International Special Committee on Radio Interference
CISPR/I	Subcommittee of CISPR dealing with EMC of information technology, multimedia equipment, and receivers
CIT	Charge-Rate Indication Teleservice
CITEL	Comision Internanericana de Telecomunicaciones
CJ	CM terminator
ckt	circuit
CL	Capabilities Select (see CR)
CLAD	Cell Assembly/Disassembly
CLASS	Bellcore service mark for signaling features such as Caller ID
CLEC	Competitive Local Exchange Carriers
CLEI	Common Language Equipment Identifiaction
CLI	Calling Line Identification
CLID	Calling Line Identity
CLIP	Calling Line Identification Presentation
CLIP	Calling Line ID Parameter
CLLI	Common Language Location Identifier (Telcordia)
CLNP	Connectionless Network Protocol
CLR	Capabilities List Request
CLR	Cell Loss Ratio
CLR	Circuit Layout Record
CM	Cable Modem
CM	Call Manager
CM	Call Menu (V.8)
CM	Channel Management
CM	Common Mode
CM	Connection Management
CMB	CRC Message Block (TIA-464-C)
CMC	Common Mail Call
CMC	Common Messaging Call
CME	Circuit Multiplication Equipment
CME	Communications Management Entity
CMI	Controlled Mode Idle
CMIP	Common Management Information Protocol
CMIS	Common Management Information Services
CMISE	Common Management Information Service Element
CMMR	Common Mode Rejection
CMMRD	Cellular Microcell/Microsystem Requirements Document
CMN	Common information
CMODES	Confidentiality Modes
CMOS	Comparison Mean Opinion Score
CMOS	Complimentary Metal Oxide Semiconductor
CMRS	Commercial Mobile Radio Services (U.S.)
CMS	Call Management Server
CMS	Call Management Signaling
CMS	Circuit Multiplication System
CMSS	Call Management Server Signaling protocol
CMT	Cellular Messaging Teleservice
CMTS	Cable Modem Termination System
CMTSD	Cellular Mobile Telephone Service Descriptions
CMTT	previous Joint CCIR/CCITT Study Group for Television and Sound Transmission
CMY	Cyan, Magenta, Yellow
CMYK	Cyan, Magenta, Yellow, Black
CN	Corporate Network
CNAD	Calling Name Delivery
CNAP	Calling Name Presentation
CNAR	Calling Name Restriction
CNG	Calling Tone (T.30)
CNG	Comfort Noise Generator
CNI	Calling Number Identification
CNI	Comfort Noise Insertion
CNID	Calling Number Identification
CNIP	Calling Number Identification Presentation
CNIP	Calling Name Identity Presentation
CNIR	Calling Number Identification Restriction
CNP	Connection Negotiation Protocol
CNR	Carrier to Noise Ratio
CNRP	Common Name Resolution Protocol
CO	Central Office
COFETEL	Comision Federal de Telecomunicaciones de Mexico
CoIP	Conferencing over IP (IMTC Activity Group)
COMM	comm.drv for Microsoft Windows
CONNEG	Content Negotiations (IETF)
COO	Cell of Origin
COPEE	Council on Office Products Energy Efficiency
COPS	Common Open Policy Service
CORBA	Common Object Request Broker Architecture
CORD	Cibernet On-line Roaming Database
CoS	Class of Service
COS	Corporation for Open Systems
COS-OST	Corporation for Open Systems Executive Industry Group
COSP	Customer Owned Outside Plant
COST	Co-Operation in the field of Science and Technology research
COTS	Commercial Off-The-Shelf
CP	Communications Protocol
CP	Continuous Presence (H.243)
CP	Customer Premises
CP	Cyclical Prefix
CPA	Combined Paging/Access
CPAN	Customer Premises Area Network
CPAP	Customer Premises Access Profile
CPCS	Common Part Convergence Sublayer
CPE	Customer Premise Equipment
CPEV	City Pair Polyethylene PVC
CPF	Compatible Protocol Field
CPF	Custom Picture Format
CPH	Call Party Handling
CP-IWF	Customer Premises - InterWorking Function (ATM Forum)
CPL	Call Processing Language
CPM	Conference Preparatory Meeting
CPM	Continuous Presence Multipoint
CPN	Calling Party Number
CPN	Customer Premise Network
CPS	Common Part Sublayer (ATMF)
CPSII	Communications Protocol Stack Independent Interface
CPS-TC	Control Specific Transmission Convergence
CPT	Cellular Paging Teleservice
CPU	Central Processing Unit
CQ	CAS Signal
CQ	Communication Quality
CQP	IPCable2Home QoS Portal
CQPSK	Compatible Differential Offset Quadrature Phase Shift Keying (Digital Modulation)
CR	Capabilities Request (see CL)
CR	Change Request (TIPHON)
CRe	Capabilities Request sent by autoanswering station at call initiation
CRC	Cyclic Redundancy Code
CRFP	Cordless Radio Fixed Parts
CR-LDP	Constraint-based Routed Label Distribution Protocol (a protocol within MPLS)
CRP	Command Repeat
CRT	Cathode Ray Tube
CRT	Chinese Remainder Theorem
CRTC	Canadian Radio and Television Commission
CRTS	Cellular Radio Telecommunications Service
CRV	Call Reference Value
CS	Canadian Standard
CS	Circuit Switched
CS1	BICC Capability Set 1
CS2	BICC Capability Set 2
CS-ACELP	Conjugate Structure ACELP
CS-PDU	Convergence Sublayer - Protocol Data Unit
CSA	Called Subscriber Internet Address
CSA	Canadian Standards Association
CSA	Carrier Serving Area
CSC	Call Signalling Channel
CSCI	Computer Software Configuration Item
CSD	Coordinated Standards Document
CSDN	Circuit Switched Data Network
CSD-P	Circuit Switched Data, Point-to-Point Service
CSE	Communication Service Equipment
CSEP	Call Setup Error Probability
CSF	Signaling Control Function
CSFP	Call Setup Failure Probability
CSI	Construction Specification Institute
CSMA/CD	Carrier Sense Multiple Access/Collision Detection
CSN	Circuit-Switched Network
CSO	Composite Second Order distortion
CSO	Curvature of the Second Order
CSPP	Computer System Policy Project
CSR	Communications Standards Review
CSS	Communication Systems Security
CSS	Communications Standards Summary
CSS	Composite Source Signal
CSS	Convolutional Spectral Shaping
CSTA	Computer Supported Telecommunications Applications
CSU	Customer Service Unit
CT	Call Trace
CT2	Cordless Telephone 2 (ETSI)
CTA	Council For Terminal Attachment
CTB	Composite Triple Beat
CTE	Connected Telecommunications Equipment
CTIA	Cellular Telecommunications Industry Association
CTE	Connected Telecommunications Equipment
CTE	Connected Terminal Equipment
CTF	Consumer Telephone Forum (Telcordia)
CTIA	Cellular Telecommunications Industry Association
CTI	Computer Telephony Integration
CTM	Cellular Text Telephone Modem
CTM	Cordless Terminal Mobility
CTN	Corporate Telecommunication Networks
CTO	Chief Technical Officers
CTP	Common Transport Protocol
CTR	Common Technical Requirements
CTRMP	Cordless Telephone Range Measurement Performance
CTX	Centrex
CU	Composite User
CUG	Closed User Group
CuT	codec under test
CV	Code Violation
CVoADSL	Channnelized Voice over ADSL
CVoDSL	Channnelized Voice over DSL
CVoSDSL	Channnelized Voice over SDSL
CVSD	Continuous Variable Slope Detection
CW	Call Waiting
CW	Continuous Wave
CWD	Call Waiting Deluxe
CWID	Call Waiting ID
CWP	Cost Work Program
CYL	Complex stutter dial report
-D-
D-AMPS	Digital AMPS
D/A	Digital to Analog
D/S	Downstream
D/TT	Digital Tie Trunk
DA	Delegated Authority
DAA	Data Access Arrangement
DAB	Digital Audio Broadcast
DAC	D/A Converter
DAL	Digital Access Line
DAM	Diagnostic Acceptability Measurement
DANS	Directory and Name Service
DANS	Distributed Access Node System
DAP	Document Application Profile
DAS	Door Answering System
DASE	DTV Application Software Environment
DAT	Digital Audio Tape
DAVIC	Digital Audio-Visual Council
DAWS	Digital Advanced Wireless Service
DB	Data Base
DBA	Dynamic Bandwith Assignment
DBM	Dual Bitmap
DBMS	Data Base Management System
DBS	Direct Broadcast Satellite
DC	Data Compression
DC	Direct Current (steady state)
DC	Directionality Classification
DCA	Dynamic Capacity Allocation
DCC	Data Country Code
DCC	Digital Control Channel
DCCH	Digital Control Channel
DCD	Data Carrier Detect
DCE	Data Circuit terminating Equipment
DCE	Digital Cellular Equipment
DCF	Dispersion Compensation Fibers
DCME	Digital Circuit Multiplication Equipment
DCMS	Digital Circuit Multiplication Systems
DCN	Disconnect (T.30 )
DCP	Datagram Control Protocol (IETF)
DCP	Digital Connectivity Probing
DCOR	Draft technical Corrigendum (ISO/IEC)
DCR	Degradation Category Rating
DCS	Digital Cellular System
DCS	Digital Command Signal (T.30)
DCS	Digital Crossconnect System
DCT	Data Calling Tone
DCT	Discrete Cosine Transform
DCT-U	Digital Cordless Telephone - U.S.
DDI	Direct Dialing In
DDoS	Distributed Denial of Service
DDR	Document Discrepancy Report
DDS	Digital Data Service
DEC	Digital Extended Command (proposed T.30 extended negotiations)
DECT	Digital Enhanced Cordless Telecommunications (ETSI)
DEG	Draft ETSI Guide
DELT	Double-Ended Loop Testing
DEN	Directory Enabled Networks
DEO	Digital End Office
DER	Digital Extended Request (proposed T.30 extended negotiations)
DES	Data Encryption Standard (U.S.)
DES	Digital Extend Signal (T.30)
DES	Draft European Standard
DF	Data Compression Format (T.class2)
DF	Deblocking Filter
DFD	Displaced Frame Difference
DFE	Decision Feedback Equalizer
DFP	Distributed Functional Plane
DFPA	Defense Fire Protection Association
DF-STP	DeFault Signal Transmission Parameters
DG	Drafting Group
DGK	Directory GateKeeper
DGN	Director General de Normas (SECOFI, Mexican Standards Organization)
DGS	Digital Station
DH	Diffie-Hellman protocol
DHC	Dynamic Host Control
DHCP	Dynamic Host Control Protocol (RFC 2131)
DHE	Document Handling Equipment
DI	Digital Interface
DI	Distribution Interface
DIAMETER	IETF protocol used for authentication, authorization and accounting
DIC	Delay Interval Compensation
DID	Direct Inward Dialing
DIG	ISDN compatible Digital Station and tie trunk (TIA-646-B)
DIL	Digital Impairment Learning
DIMRS	Digital Integrated Mobile Radio System
DIN	Deutsche Institut fur Normung (German Standardization Institute)
DIS	Digital Identification Signal
DIS	Draft International Standard (ISO)
DISA	Defense Information Systems Agency
DISXML	Extended Markup Language
DJGPP	MSDOS port of gcc
DKTS	Digital Key Telephone Station
DLC	Digital Loop Carrier
DLC	Dynamic Load Control
DLCI	Data Link Connection Identifier
DLL	Dynamic Link Library
DLP	Data Protocol (H.DLP)
DM	Differential Mode
DMA	Direct Memory Access
DMH	Data Message Handler
DMI	Desktop Management Interface
DMI	Draft Miscellaneous Work Item (ETSI)
DMIF	DSM-CC Multimedia Integration Framework
DMOS	Degradation MOS
DMP	Downlink Measurement Protocol
DMT	Discrete MultiTone
DMTF	Desktop Management Task Force
DMV	Differential Motion Vector
DN	Directory Number
DND	Do Not Disturb
DNI	Digital Negotiation Information Signal
DNIS	Dialed Number Identification Service
DNK	Digital Not acKnowledge
DNS	Domain Name Server
DoC	Declaration of Conformity
DOC	Department of Commerce
DOC	Department of Communications (Canada)
DOCSF	Display Oriented Color Space for Facsimile
DOCSIS	Data Over Cable Service Interface Specification
DoD	Department of Defense (U.S.)
DOE	Department of Energy (U.S.)
DOL	Data Off-Loading
DoS	Denial of Service
DOS	Department of State (U.S.)
DP	Data Privacy
DP	Data Pump
DP	Dial Pulse
DPA	Data Privacy Algorithm
DPA	Document Printing Application
DPBX	Digital PBX
DPCM	Digital PCM Modem
DPI	Dots Per Inch
DPL	Digital Power Line (Q1/15)
DPS	Data Partitioned Slice
DPS	Dynamic Power Save
DPNSS	Digital Private Network Signaling System
DPSK	Differential Phase Shift Keying
DPT	Distribution-Preserving Tomlinson
DQoS	Dynamic Quality of Service
DQUANT	Field for modified quantization mode (H.263+)
DR	Discrepancy Report
DRA	Dynamic Rate Adaptation
DRC	Dynamic Rate Change
DRM	Digital Rights Management
DRQ	Disengage Request
DRP	ear Drum Reference Point
DRR	Dynamic Rate Repartitioning
DRT	Diagnostic Rhyme Test
DRUMS	Detailed Revision/Update of Message
DS0	64 kbit/s Channel
DS1	1.544 Mbit/s T1 Interface
DS3	44.736 Mbit/s T3 Interface
DSA	Directory System Authentication
DSAA	DECT Standard Authentication Algorithm
DSAP	Data Services Access Profile
DSAT	Digital Supervisory Audio Tone
DSC	DECT Standard Cipher
DSC	Dedicated Signaling Channel
DSCP	Differentiated Services Code Point
DSI	Digital Speech Interpolation
DSL	Digital Subscriber Line
DSL	Document SeLection
DSLAM	DSL Access Multiplexer
DSLF	DSL Forum
DSL-TILC	DSL Test Implementation Liaison Committee (Japan)
DSM-CC	Digital Storage Media - Command and Control
DSMCC	Digital System Multimedia Communication Control
DSN	Delivery Status Notification
DSN	Disposition Service Notification
DSNG	Digital Satellite News Gathering
DSP	Digital Signal Processing
DSR	Data Set Ready
DSR	Distributed Speech Recognition
DSR	Dynamic Symbol Reordering
DSREQ	Data Service Request
DSS1	Digital Subscriber Signaling 1
DST	Destination host
DSU	Data Service Unit
DSV	Distributed Speaker Verification
DSVD	Digital SVD
DSX	Digital Signal Cross-Connect
DT	Dual Tone
DTA	Digital Terminal and Access Project (ETSI)
DTAAB	DECT Technical Advisory Ad hoc Board
DTAM	Document Transfer Access Method
DTAP	Direct Transfer Application Part
DTC	Digital Traffic Channel
DTC	Digital Transmit Command
DTC	Domain Traffic Class
DTCX	Double Transcompression
DTD	Document Type Definition
DTE	Data Terminal Equipment
DTG	Digital TV Group (UK)
DTIF	Disabilities Issues Task Force
DTL	Designated Transit List
DTM	Dynamic synchronousTransfer Mode
DTMF	Dual Tone Multi Frequency
DTR	Data Terminal Ready
DTR	Draft Technical Report (ETSI)
DTS	Definitive Telefax Standard
DTV	Digital Television
DTX	Discontinuous Transmission
DUT	Device Under Test
DV	Digital Video
DVB	Digital Video Broadcasting
DVB-CSA	Digital Video Broadcasting - Common Scrambling Algorithm
DVB-MUG	Digital Video Broadcasting Ð MHP Umbrella Group
DVB-S	Digital Video Broadcasting - Satellite
DVB-T	DVB Terrestrial
DVCC	Digital Verification Color Code
DVD	Digital Versatile Disk (also Digital Video Disk)
DVEM	Differential Vector Error Magnitude
DWDM	Dense Wavelength Division Multiplexing

More Acronym Definitions: