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Computing & IT >> Telecom Abbreviations

Look through 4999 acronyms and abbreviations related to Telecom:

• IPB — Invision Power Board
• XFMR — Transformer
• CBCU — Centralized Broadband Control Unit
• DDRS — Dynamic Data Rate Selection
• DCE — Data Circuit-terminating Equipment
• DOE — Distributed Object Environment
• SYN — Synchronous
• DWDM — Dense Wavelength Division Multiplexing
• EBITDA — Earnings before Interest, Taxes, Depreciation and Amortization
• ECG — Electrocardiogram
• CSR — Customer Service Representative
• CONG — Congestion message
• CT — Computed Tomography
• GFSK — Gaussian Frequency Shift Keying
• LAN — Local Area Network
• APR — Annual Percentage Rate
• ETA — Estimated Time of Arrival
• IQ — Intelligence Quotient
• DAM — Diagnostic Acceptability Measure
• D-H — Diffie-Hellman
• DWDM — Dense Wavelength-Division Multiplexing
• ISAR — Inverse Synthetic-Aperture Radar
• CSMA/CA — Carrier Sense Multiple Access/Collision Avoidance
• MLS — Microwave Landing System
• ADM — Add-Drop Multiplexer
• FTP — File Transfer Protocol
• CSMA/CD — Carrier Sense Multiple Access with Collision Detection
• YTD — Year To Date
• YMMV — Your Mileage May Vary
• FDIC — Federal Deposit Insurance Corporation
• CSMA/CD — Carrier sense multiple access / collision detection
• ISO — In Search Of
• CSMA — Carrier Sense Multiple Access
• MAN — Metropolitan Area Network
• OIC — Oh I See
• ECU — Electronic Control Unit
• AUP — Acceptable Use Policy
• TNYWR — The Number You Will Receive
• F2F — Face To Face (also Meeting In Person)
• DSCP — Differentiated Services Control Point
• ROM — Read-Only Memory
• WWW — World Wide Web
• TEMIP — Telecommunications Management Information Platform
• ASAP — As Soon As Possible (pronounced AY-sap)
• CUG — Closed User Group
• BRDF — Bidirectional Reflectance Distribution Function
• BVR — Beyond Visual Range
• CPE — Customer Premises Equipment
• DAC — Discretionary Access Control
• DND — Do Not Disturb

• IRC — Internet Relay Chat
• RFQ — Request For Quotation
• LASER — Light Amplification By Stimulated Emission Of Radiation (cf. Maser)
• IT — Information Technology
• DBORS — Data Base of Records
• WTG — Way To Go
• CCM — counter-countermeasure
• IAMAI — Internet and Mobile Association of India
• CPU — Central Processing Unit
• CCSDS — Consultative/Consultative Committee for Space Data Systems
• MBR — Master Boot Record
• VIP — Very Important Person
• CDR — Critical Design Review
• CSA — Canadian Space Agency
• ACC — Adaptive Cruise Control
• SAR — Search And Rescue
• UK — United Kingdom of Great Britain and Northern Ireland
• BIP — Bit-Interleaved Parity
• DFD — Displaced Frame Difference
• ISO — International Organization for Standardization
• QC — Quality Control
• AATSR — Advanced Along-Track Scanning Radiometer
• AFAIK — As Far As I Know
• ESA — European Space Agency
• ANSI — American National Standards Institute, Inc.
• DBMS — Database Management System
• BUR — Bandwidth Usage Redundancy
• EAP — Employee Assistance Program
• WML — Wireless Markup Language
• LED — Light-Emitting Diode
• WDM — Wavelength Division Multiplexing (fiber optics)
• FEMA — Federal Emergency Management Agency
• BTW — By The Way
• PDR — Preliminary Design Review
• ACK — ACKnowledgment
• IRL — In Real Life
• LRJ — Location Reject
• LCD — Liquid Crystal Display
• EDI — Electronic Data Interchange
• UDP — User Datagram Protocol (FDDI related)
• FET — Field Effect Transistor
• ABI — Application Binary Interface
• RWR — Radar Warning Receiver
• FAR — Federal Aviation Regulation
• CD — Compact Disc
• ACE — Access Control Entry
• XML — Extensible Markup Language
• VM — Voice Mail
• RPI — Retail Price Index
• MMS — Multimedia Messaging Service

• AC — Alternating Current
• WWW3 — World Wide Web Consortium
• CY — Calendar Year
• MB — Megabyte
• CS — Computer Science
• ATM — Automatic Teller Machine
• OEM — Original Equipment Manufacturer (usually in reference to car parts)
• NFS — Network File System
• NOS — Network Operating System
• CV — Curriculum Vitae
• ACH — Automated Clearing House
• LRU — Line Replaceable Unit
• STS — Space Transportation System
• IRR — Internal Rate of Return
• ASA — American Standards Association
• EIS — Executive Information System
• QFSK — Quadrature Frequency Shift Keying
• RDF — Resource Description Framework
• PDH — Plesiochronous Digital Hierarchy
• ATTN — Attention
• GSM — Global System for Mobile Communications
• CAUCE — Coalition Against Unsolicited Commercial Email
• ALC — Automatic Level Control
• Y2K — Year 2000
• SDMA — Space Division Multiple Access
• ADD — Addendum
• GATT — General Agreement on Tariffs and Trade (government)
• DSA — Digital Signature Algorithm
• AES — Advanced Encryption Standard
• APT — Automatic Picture Transmission
• COB — close of business (End of duty day)
• C4I — Command, Control, Communications, Computers, & Intelligence
• CCB — Change Control Board
• AAC — Advanced Audio Coding
• HTTP — Hypertext Transfer Protocol
• SMTP — Simple Mail Transfer Protocol
• ISP — Internet Service Provider
• PDA — Personal Digital Assistant
• EOM — End Of Message
• CCIS — Common Channel Interoffice Signaling
• ATA — Area Transportation Authority
• EFF — Electronic Frontier Foundation
• ATOM — Any Transport over MPLS (Multi-Protocol Label Switching)
• CGI — Common Gateway Interface
• CEO — Chief Executive Officer
• ADM — Add/Drop Multiplexer
• ADR — Address
• TQM — Total Quality Management
• NB — Nota Bene. Abbreviation of the Latin expression commonly used to emphasise the importance of a statement, literally meaning 'observe well'. Or less politely and more amusingly, No Bullshit.
• AES — Auger Electron Spectroscopy

• GIS — Geographic Information System
• DDL — Data Definition Language
• EW — Electronic Warfare
• R&D — Research & Development
• RNC — Radio Network Controller
• BPM — Beats Per Minute
• IP — Internet Protocol
• NIC — Network Interface Card
• QI — Quality Improvement
• LLC — Limited Liability Company
• GPRS — General Packet Radio Service
• SCSI — Small Computer System Interface
• DME — Distance Measuring Equipment
• ABR — Available Bit Rate
• WAN — Wide Area Network
• ACD — Automatic Call Distributor
• RF — Radio Frequency
• POC — Point Of Contact
• AC — Access Control
• RFP — Request For Proposal
• MST — Mountain Standard Time
• MOU — Memorandum of Understanding (an MOU between Food & Drug Administratin and a regulatory agency in another country allows mutual recognition of inspections)
• SP — Service Provider
• SAN — Storage Area Network
• CR — Carriage Return
• TCB — Trusted Computing Base
• NPI — New Product Introduction
• DMSP — Defense Meteorological Satellite Program (U.S.)
• VAT — Value Added Tax
• DTX — Discontinuous Transmission
• AVHRR — Advanced Very High Resolution Radiometer  
• CDR — Call-Detail Record
• RU — Are You?
• VR — Virtual Reality
• ATM — Asynchronous Transfer Mode
• COR — Carrier Operated Relay
• ASME — American Society of Mechanical Engineers
• ASR — Airport Surveillance Radar
• DFS — Distributed File System
• UAV — Unmanned Aerial Vehicle
• PUHU — Pick Up Hang Up
• BECN — Backward Explicit Congestion Notification
• DMX — De-MultipleXer
• RFC — Request For Comment
• VVX — Voice and Video eXchange
• CU — Control Unit
• APIC — Advanced Programmable Interrupt Controller
• MRI — Magnetic Resonance Imaging
• PDT — Pacific Daylight Time
• ACFQ — Absence Compensation Fair Queuing

• WWW — World Weather Watch
• RPC — Remote Procedure Call
• CBC — cipher block chaining
• WBS — Work Breakdown Structure
• SCC — Standards Council of Canada
• DB — Decibel
• TCP — Transmission Control Protocol
• WEP — Wired Equivalent Privacy
• THX — Thanks
• ATF — Advanced Tactical Fighter
• CB — Call Back
• AD — Active Directory
• TC — Telephone Call
• JAXA — Japan Aerospace Exploration Agency
• NMSE — Normalized Mean Square Error
• CAE — Computer-Aided Engineering
• BBS — Bulletin Board Service
• AP — Application Protocol
• IM — Instant Message
• BS — Base Station
• S X S — Step-by-Step
• SRAM — Static Random Access Memory (ess-ram)
• PDF — Portable Document Format (created by Adobe Acrobat)
• DTE — Data Terminal Equipment
• CFE — Contractor-Furnished Equipment
• PCB — printed circuit board
• AIS — Automated Information System
• SIG — Special Interest Group
• CIM — Corporate Information Management
• ATM — Adobe Type Manager
• FAA — Federal Aviation Administration
• CPT — Carriage Paid To
• CIO — Chief Information Officer
• SD — Standard Deviation
• AME — Amplitude Modulation Equivalent
• TAC — Technical Assistance Center
• EC — European Commission
• 100BASE-T2 — 100 Megabits per Second, Baseband, Two-pair Category 3 UTP cables
• PLMN — Public Land Mobile Network
• GRE — Generic Routing Encapsulation
• IPO — Initial Public Offering
• BTU — British Thermal Unit
• RM — Resource Management
• CMI — Computer Managed Instruction
• WB — Welcome Back
• ABC — activity based costing
• CAM — Computer-Aided Mapping
• IMPACT — Integrated Manufacturing Precision Assembly Cellular Technology
• SLA — Service Level Agreement
• ISRO — Indian Space Research Organisation

• I/O — Input/Output
• FX — Foreign Exchange
• DMTS — Distinguished Member Of Technical Staff
• ISO — Infrared Space Observatory
• EST — Eastern Standard Time
• Q&A — Question & Answer
• VDS — Variable Depth Sonar
• DIT — Directory Information Tree
• NIH — Not Invented Here
• MOS — Model Output Statistics
• API — Application Programming Interface
• PPM — parts per million
• UAS — Unavailable Seconds
• ARPA — Advanced Research Projects Agency (made early internet)
• SQA — Software Quality Assurance
• AOA — Angle Of Arrival
• LCP — Link Control Protocol
• CC — Call Control
• CM — Configuration Management
• FCW — Federal Computer Week
• CPM — Critical Path Method
• MSN — Microsoft Network
• JV — Joint Venture
• DHCP — Dynamic Host Configuration Protocol
• AT — Access Tandem
• AM — Ante Meridian
• AIR — Account Information and Refill
• NATO — North Atlantic Treaty Organisation
• MDA — Monochrome Display Adapter
• EBCDIC — Extended Binary Coded Decimal Interchange Code (pronounced Eb-see-dik) (cf. BCD)
• TM — Technical Manual
• ME — Mobile Equipment
• MIC — Message Integrity Check
• OSS — Operational Support System
• NMT — Nordic Mobile Telephone
• MS — Message Store
• DSA — Directory System Agent
• PLD — Programmable Logic Device
• S-BCCH — Short Message Service Broadcast Control Channel
• PAR — Precision Approach Radar
• CDS — Cell Directory Service
• AM — Amplitude Modulation
• SME — Subject Matter Expert
• CC — Carbon Copy
• CIS — Commonwealth of Independent States
• SLIP — Serial Line Interface Protocol
• MS — Mobile Station
• DT — DWDM (Dense Wavelength Division Multiplexing) Terminal
• TV — Television
• DOA — dead on arrival

• UPS — Ultraviolet Photoelectron Spectroscopy
• QMS — Quality Management System
• QOS — Quality of Service
• MOB — Mobile
• MAC — Message Authentication Code
• TS — Technical Specification
• ASTM — American Society for Testing and Materials (Philadelphia, Pennsylvania)
• DES — Data Encryption Standard
• MTBF — Mean Time Before Failure
• AF — Audio Frequency
• SMS — Short Message Service
• ATS — applications technology satellite
• MPI — Message Passing Interface
• M — Meter
• YP — Yellow Pages
• CRL — Certificate Revocation List
• UHF — Ultra High Frequency (300-3000 MHz; 1m-10cm)
• ACL — Access Control List
• FC — Fibre Channel
• SGML — Standard Generalized Markup Language
• BCC — Blind Carbon Copy
• SDR — Special Drawing Rights
• BRB — Be right back
• PAL — Programmable Array Logic
• EMG — Electromyogram
• EGA — Enhanced Graphics Adapter
• FFT — Fast Fourier Transform
• TPDU — Transport Protocol Data Unit
• USB — Universal Serial Bus
• AGP — Accelerated Graphics Port
• ICT — Information and Communication Technology
• IS — Intermediate System
• ASCII — American National Standard Code for Information Interchange
• IW — Information Warfare
• DLC — Digital Loop Carrier
• TBD — To Be Decided
• EAP — Extensible Authentication Protocol
• ATCRBS — Air Traffic Control Radar Beacon System
• VM — Virtual Machine
• RCU — Remote Control Unit
• BBU — Baseband Unit
• LLC — Logical Link Control
• GUI — Graphical User Interface (goo-ey)
• CS — Cable Select
• UAN — Universal Access Number
• COMJAM — Communications Jamming
• BPRZ — Bipolar Return-to-Zero
• JIS — Japanese Industrial Standard
• HDLC — High-Level Data Link Control
• LCN — Logical Channel Number

• ASK — amplitude shift keying
• TNSTAAFL — There's No Such Thing As A Free Lunch
• AML — Amplitude Modulated Link
• Z — Zero
• A-KEY — Authentication key
• GPS — Global Positioning System (ex-NAVSTAR)
• B-ICI — Broadband Inter-Carrier Interface
• PO — Purchase Order
• SEM — Space Environment Monitor
• RCC — Rescue Coordination Center
• RDBMS — Relational Database Management System
• AT — Advanced Technology
• RAD — Rapid Application Development
• RACON — Radar Beacon
• SEC — Software Engineering Center
• ICMP — Internet Control Message Protocol
• ATC — Air traffic control
• VIRUS — Vital Information Resources Under Siege
• F — Fellow
• HW — Hardware
• VOP — Voice Over Packet
• DIS — Distributed Interactive Simulation
• SSM — Source-Specific Multicast
• LSR — Local Service Request
• MF — Medium Frequency
• SA — Scientific American
• EPA — Environmental Protection Agency (US)
• CBDS — Connectionless Broadband Data Service
• CLNP — ConnectionLess-mode Network Protocol
• ECN — Explicit Congestion Notification
• DNS — Domain Name System
• CERT — Computer Emergency Response Team
• DARPA — Defense Advanced Research Projects Agency (US)
• AE — Application Entity
• X-BAR — Crossbar telephone exchange
• OMG — Object Management Group
• ISS — International Space Station
• ADPE — Automatic Data Processing Equipment
• DPC — Destination Point Code
• EDS — Electronic Data Systems Corporation
• AGC — Automatic Gain Control
• LEO — Low Earth Orbit (satellite communications)
• PM — Preventive Maintenance
• E — Energy
• RIP — Routing Information Protocol
• IDT — Integrated Digital Terminal
• EAS — Extended Area Service
• CAC — Carrier Access Code
• WS — Workstation
• NI — Network Interface

• MHS — Microwave Humidity Sounder
• DC — Direct Current
• DLR — Design Layout Record
• ACM — Association for Computing Machinery
• ADT — Abstract Data Type
• SAS — Statistical Analysis System
• ABET — Accreditation Board for Engineering and Technology, Inc.
• ASR — Access Service Request
• FXO — Foreign Exchange Office
• ARPANET — ARPA Network
• EU — European Union (1994; formerly referred to as the EEC or EC)
• ARPU — Average Revenue Per User
• SM — Senior Member
• ADSL — Asymmetric Digital Subscriber Line
• CIC — Circuit Identification Code
• MC — Message Center
• TEC — Total Electron Content
• CIM — Common Information Model
• LF — Low Frequency
• PNG — Portable Network Graphics (graphic file standard/extension)
• VB — Visual Basic
• NSF — National Sanitation Foundation
• EVP — Executive Vice President
• RTS — Request To Send
• CABS — Carrier Access Billing System
• IPX — Internetwork Packet Exchange
• DS — Digital Signal
• MS — Management System
• UR — Your
• OTN — Optical Transport Network
• TTYL — Talk To You Later (Internet Slang)
• AR — Access Rate
• SDD — Software Design Document
• NSA — National Security Agency
• B3ZS — bipolar 3-zero substitution
• VHF — Very High Frequency
• RFI — Radio Frequency Interference
• TLS — Transport Layer Security
• RT — Remote Terminal
• DCE — Distributed Computing Environment
• RFS — Request For Service
• SCP — Service Control Point
• CO — Certificate of Origin
• X-ON — Transmitter On
• BSD — Berkeley Software Distribution
• IP — Intelligent Peripheral
• CW — Continuous Wave
• CUL — See You Later
• DOM — Document Object Model
• VOD — Video On Demand

• OM — Old Man
• AS — Autonomous System
• PE — Polyethylene
• HSDPA — High-Speed Downlink Packet Access
• OBO — Or Best Offer
• BACP — Bandwidth Allocation Control Protocol
• FA — Functional Area
• ZIP — Zone Information Protocol
• SEI — Software Engineering Institute
• ATSR — Along-Track Scanning Radiometer
• CGI — Computer-Generated Imagery
• RDY — Ready
• AFP — AppleTalk Filing Protocol
• DQPSK — Differential Quadrature Phase-Shift Keying
• TB — Terabyte
• UA — User Agent
• IVR — Interactive Voice Response (telephone technology)
• X-OFF — Transmitter Off
• JSC — Johnson Space Center (Houston, TX)
• OSPF — Open Shortest Path First (ATM)
• SIL — Speech Interference Level
• MP — Multilink Protocol
• MSE — Mobile Subscriber Equipment
• MD — Mediation Device
• MS — Millisecond
• AU — Audio Unit
• AE — Account Executive
• PDN — Public Data Network
• NPV — Net Present Value {economics}
• ADF — Automatic Direction Finder
• DSC — Differential Scanning Calorimetry
• BBS — Bulletin Board System
• RAM — random-access memory
• WPS — Wireless Priority Service
• IS — International Standard
• H323 — ANSI standard for format over IP
• TBD — To Be Determined
• URI — Uniform Resource Identifier
• NYSE — New York Stock Exchange
• ACE — Advanced Computing Environment
• TN — Telephone Number
• ECT — Explicit Call Transfer
• URL — Universal Resource Locator
• IN — Intelligent Network
• DA — Destination Address
• NTFS — New Technology File System
• PRF — Pulse Repetition Frequency
• BCD — Binary-Coded Decimal
• WB — Write Back
• CAN — Campus Area Network

• SWAG — Scientific Wild Ass Guess
• CCTV — Closed-circuit television
• MSU — Microwave Sounding Unit
• PVT — Private
• APC — American Power Conversion
• SPI — Service Provider Interface
• BRA — Basic Rate Access
• IETF — Internet Engineering Task Force
• NOTAM — Notice to Airmen
• BT — British Telecommunications
• DCP — Design Change Package
• CA — Certificate Authority
• TOS — Type Of Service
• HF — High Frequency
• AMT — Amount
• CEV — Controlled Environment Vault
• CT — Computer Telephony
• WACN ID — Wide Area Communications Network IDentifier
• STP — Spanning Tree Protocol
• PWD — Password
• CIA — Central Intelligence Agency
• COO — Cost of Ownership
• ZDBOP — Ziff-Davis Benchmark Operation
• ZIP — Zone Improvement Plan
• RCV — Receive
• COM — Component Object Model
• YGWYPF — You Get What You Pay For
• STK — Satellite Tool Kit
• CU — See You
• NESDIS — National Environmental Satellite, Data, and Information Service
• BT — BlueTooth
• SCTP — Stream Control Transmission Protocol
• AFC — Automatic Frequency Control
• P&L — Profit and Loss statement
• SVC — Scalable Video Coding
• NIS — Network Information Service
• ISI — Inter-Symbol Interference
• PECVD — Plasma-Enhanced Chemical Vapor Deposition
• SVC — Switched Virtual Connection
• VLL — Virtual Leased Line
• OMS — Optical Multiplex Section
• WMAN — Wireless Metropolitan Area Network
• DRAM — Dynamic Random Access Memory (dee-ram) (computing)
• AMI — Advanced Metering Infrastructure
• WG — Working Group
• UL — Uplink
• ACK — Acknowledge (telecommunications; Cf. NAK)
• CATV — Community Antenna Television
• M — Management
• PMA — Physical Medium Attachment

• PT — Project Team
• ACR — Attenuation Crosstalk Ratio
• NIC — Network Information Center
• D-NBAP — Dedicated Node B Application Part
• NAS — Network Access Server
• MCU — Multipoint Control Unit
• C-NBAP — Common Node B Application Part
• ARP — Address Resolution Protocol (ATM)
• STI — Speech Transmission Index
• SBC — Session Border Controller
• FCA — Free Carrier
• NEC — National Electrical Code
• AM — Activity Manager
• SAN — System Area Network
• MSR — Microwave Scanning Radiometer
• DUP — Duplicate
• ERT — Emergency Response Team
• FR — Frame Relay
• TRM — Technical Reference Model
• TE — Traffic Engineering
• PCI — Peripheral Component Interconnect
• XA-FR — Exchange Access Frame Relay
• DID — Digital Information Display
• MDA — Model Driven Architecture
• HSD — High Speed Data
• FE — Far End
• LF — Line Feed
• RH — Relative Humidity
• LZ — Landing Zone
• EAC — Engineering Accreditation Commission
• GDS — Global Distribution System
• ADEOS — ADvanced Earth Observing Satellite (Japan)
• SCN — Switched Circuit Network
• OPC — Originating Point Code
• NA — Not Applicable
• ISA — Industry Standard Architecture
• DTR — Data Terminal Ready
• RM — Regional Manager
• RDP — Radar Data Processing
• PSD — Phase-Sensitive Detector
• CSAT — Customer Satisfaction
• RA — Risk Analysis
• SPADATS — Space Detection And Tracking System
• DMARC — Demarcation point
• OSI — Open Systems Interconnection (iso Standard)
• EEC — European Economic Community (predecessor of the European Union|EU)
• Y — Yes
• AFS — Andrew File System
• ARC — Army Reuse Center
• BIP — Band Interleaved by Pixel

• CAB — Conformity Assessment Body
• SVD — Singular Value Decomposition
• CTS — Clear To Send
• RFO — Reason For Outage
• DX — Duplex
• RFI — Request For Information. Sales department shorthand. Special priority when use in conjunction with RFN (see below).
• DAP — Directory Access Protocol
• ES — Errored Second
• CBT — Computer Based Training
• LD — Long Distance
• UAX 14 — Unit Automatic eXchange type 14
• PSTN — Public Switched Telephone Network
• MOL — Manned Orbiting Laboratory
• NMS — Network Management System
• BER — Bit-Error Rate
• TOP — Technical Office Protocol
• TG — Task Group
• STM — Short Term Memory
• SPC — Stored Program Control
• DQE — Detective Quantum Efficiency
• NNM — Network Node Manager
• MRC — Monthly Recurring Charge
• MOD — Modify
• BIS — Bureau of Indian Standards
• GB — Gigabyte
• FIFO — First In, First Out
• PGP — Pretty Good Privacy (encryption)
• BS — Beam Splitter
• TCP/IP — transmission control protocol/internet protocol
• OAS — Organization of American States
• IIS — Internet Information Services
• QAM — quadrature amplitude modulation
• AXE 10 — Series of electronic telephone exchanges from L.M. Ericsson
• AIS — Alarm Indication Signal
• CNM — Customer Network Management
• NCS — National Communications System
• VAC — Vacant
• CRT — Cathode Ray Tube (type of TV)
• P — Predicted
• OC — Optical Carrier
• W3C — World Wide Web Consortium
• FUP — Fair Use Policy
• PDS — Protected Distribution System
• TLC — The Learning Channel
• LP — Low Pressure
• DEC — Decimal
• MLS — Multiple Listing Service
• FITS — Flexible Image Transport System
• Y — Yttrium
• CHAP — Challenge Handshake Authentication Protocol (ATM)

• NLMS — Normalized Least Mean Square
• USD — United States Dollar
• PAN — Personal Area Network
• CB — Common Battery
• MVS — Multiple Virtual Storage
• TWT — Traveling Wave Tube
• FCP — Fibre Channel Protocol
• CF — Compact Flash
• COQ — Cost Of Quality
• EEPROM — Electrically Erasable Programmable Read-Only Memory
• AFSK — Audio Frequency Shift Keying
• ASR — Automatic Speech Recognition
• DSSS — Direct Sequence Spread Spectrum
• CAV — Constant Angular Velocity
• PS — Product Specification
• MIS — Management Information System (OSHA)
• QA — Center for Quality Assurance in International Education
• RSRQ — Reference Signal Received Quality
• AEW — Airborne Early Warning
• DVP — Digital Voice Privacy
• PGA — Programmable Gate Array
• E-LEAD — Ear Lead
• VOL — Volume
• BST — British Summer Time
• ESS — Electronic Switching System
• TSR — Telecommunications Service Request
• LEN — Line Equipment Number
• METRO — Metropolitan
• FAQ — Frequently Asked Questions (sometimes Pronounced Fak)
• ARG — Argument
• OCR — Optical Character Recognition
• IS — Information System
• PPB — parts per billion (109)
• DC — Display Controller
• TE — Test Equipment
• CG — Coast Guard
• DCN — Disconnect
• CIR — Committed Information Rate (Frame Relay)
• RT — Response Time
• SAS — Special Access Surcharge
• ECAC — European Civil Aviation Conference
• AAS — Adaptive Antenna System
• VT — Vacuum Tube
• BG — Background
• ATA — Analog Telephone Adapter
• PD — Public Domain
• LPC — Linear Predictive Coding
• DC — Disconnected
• TI — Time Interval
• PDS — Planetary Data System

• EPR — Electron Paramagnetic Resonance
• AOI — Area Of Interest
• EX — Exercise
• MCSD — Microsoft Certified Solution Developer
• LEP — Large Electron Positron
• CDMA — Code Division Multiple Access (voice/data transmission)
• CAD — Computer Aided Designer
• ETS — European Telecommunication Standard
• A — Anode
• DCS — Digital Cross-connect System
• VC — Virtual Channel
• FDL — Facility Data Link
• CS — Convergence Sublayer (ATM)
• FDDI — Fiber Distributed Data Interface
• ITSEC — Information Technology Security Evaluation Criteria
• DUC — Digital Up-Converter
• SL — Single Line
• DOD — United States Department of Defense
• CER — Cell Error Ratio
• JPL — Jet Propulsion Laboratory (California Institute of Technology) (NASA)
• APM — Advanced Power Management
• DAL — Dedicated Access Line
• EIP — Equipment installation procedure
• ADC — Analog-Digital Converter
• DL — Digital Library
• SHF — Super High Frequency
• DDS — Digital Data Service
• UP — User Profile
• COO — Chief Operation Officer
• CATV — Cable Television
• CAM — Content Addressable Memory
• PE — Probable Error
• DSS — Decision Support System
• ACT — Activity
• CAM — computer aided manufacturing
• SF — Single Frequency
• FE — Finite Element
• BSOD — Blue Screen Of Death
• PTA — Pakistan Telecommunication Authority
• LU — Logical Unit
• MCD — Magnetic Circular Dichroism
• ECP — Encryption Control Protocol
• DOJ — Department of Justice (US)
• AS — Access System
• IEC — International Electrotechnical Commission
• DCS — Digital Cellular System
• YL — Young Lady
• AIN — Advanced Intelligent Network
• OLAP — Online Analytical Processing
• AMLCD — Active Matrix Liquid Crystal Display

• CMT — Cadmium Mercury Telluride
• AEC — Architecture, Engineering, Construction
• CIS — CompuServe Information Service
• SNMP — Simple Network Management Protocol (ATM)
• ISDN — Integrated Services Digital Network
• BOC — Bell Operating Company
• SML — Service Management Layer
• ARA — Apple Remote Access
• ASQC — American Society for Quality Control's
• 9 — Nine
• TE — Terminal Equipment
• MCA — Micro Channel Architecture
• FAA — Federal Aviation Agency
• CBP — Coded Block Pattern
• SD — Software Development
• SQL — Structured Query Language
• AMD — Advanced Micro Devices, Inc. (producer of computer chips)
• MHS — Message Handling System (electronic)
• VPN — Virtual Private Network (ATM)
• AAAS — American Association for the Advancement of Science
• EPABX — Electronic Private Automatic Branch Exchange
• OS — Operating System
• DMA — direct memory access (computer term)
• PDU — Protocol data unit (such as segment, packet, frame, etc.)
• PUB — Publication (file name extension)
• SAR — Specific Absorption Rate
• NA — Network Adapter
• LT — Less Than
• BNSC — British National Space Centre
• PIN — Personal Identification Number
• CO — Central Office
• SLP — Service Location Protocol
• DBS — Direct Broadcast Satellite
• ECO — Engineering Change Order
• PG — Page
• OTS — Optical Transmission Section
• ROSAT — Roentgen Satellite
• ATN — Aeronautical Telecommunication Network
• CU — Channel Unit
• EDVAC — Electronic Discrete Variable Automatic Computer
• BR — Branch
• SAIC — Science Applications International Corporation
• SOHO — Small Office Home Office
• BERT — Bit Error Rate Tester (telecommunication)
• T-CARRIER — Trunk Carrier
• CAA — Civil Aviation Authority
• E — Echo
• AMI — Alternate Mark Inversion
• BS — Broadcast Satellite
• AAF — Advanced Authoring Format

• I.LINK — IEEE 1394, High Performance Serial Bus, implementation
• SBC — Southwestern Bell Corporation
• CTD — Cumulative Trauma Disorder
• AT&T — American Telephone & Telegraph
• LPE — Liquid Phase Epitaxy
• OAM&P — Operations, Administration, Maintenance & Provisioning
• Q — Quadrature
• TSB — Telecommunication Standardization Bureau
• AUD — Audit
• RT — Radiotelephone
• STP — Signal Transfer Point
• CDC — Connected Device Configuration
• IV — Initialization Vector
• BYOD — Bring Your Own Device
• KISS — Keep It Simple Stupid
• DCOM — Distributed Component Object Model
• BSS — Basic Service Set
• ACE — Adaptive Communication Environment
• VOA — Voice Of America
• PSK — phase-shift keying
• RJ-25 — Registered Jack type 25 (6-wire connector)
• WYSIWYG — What You See Is What You Get (pronounced Wizzy-wig. See Entry For Derived Acronyms)
• AMHS — Automated Message Handling System
• TLK — Talk
• DCS — Digital Cross-Connect
• TMS — Time Management System
• EOT — End Of Transmission
• FCS — Frame check sequence (Ethernet)
• PIC — Peripheral Interface Controller
• EMEA — Europe, Middle East and Africa
• IT — Integration Test
• LLU — Local Loop Unbundling
• CCTA — Central Computer and Telecommunications Agency
• BS — Backing Store
• BPR — Business Process Re-engineering
• AADC — Automated Area Distribution Center
• BBM — Blackberry Messenger
• SIL — Silence
• FRS — Family Radio Service
• TO — Technical Order
• RFD — Request For Discussion
• IRS — U.S. Internal Revenue Service
• RAEX — Roaming Agreement EXchange
• SA — Source Address
• C — Cost
• TCR — Temperature Coefficient of Resistance
• PDC — Personal Digital Cellular
• SOW — Statement Of Work
• ADL — Advanced Distributed Learning
• JAN — Joint Army-Navy

• POS — Point Of Sale.Retail term, being the physical point at which products are displayed on shelves or paid for at the checkout, as in the EPOS acronym.
• SPM — Scanning Probe Microscope
• SMR — Specialized Mobile Radio
• NOAA — National Oceanic and Atmospheric Administration (US)
• TCM — Trellis-Coded Modulation
• RPM — Revolutions Per Minute, (Rotations Per Minute)
• EM — Electromigration
• RSVD — Reserved
• MAI — Multiple Access Interference
• PC — Peripheral Controller
• DSL — Digital Subscriber Line
• SIM — Subscriber Identity Module
• ASIC — application-specific integration circuit
• DOS — Disk Operating System
• NIC — Network Interface Controller
• RTN — Regional Telecommunication Network
• ELF — Extremely Low Frequency
• VLF — Very Low Frequency
• GOS — Grade Of Service
• TAD — Telephone Answering Device
• NNTP — Network News Transfer Protocol
• ADN — Advanced Digital Network
• MTTR — Mean Time To Repair
• SSL — Secure Socket Layer
• PC — Personal computer (host)
• ROFL — Rolling on the floor laughing
• PERT — Program Evaluation and Review Technique
• DDL — Digital Data Link
• SZ — Seizure
• 1000BASE-T — 1000 Megabits per Second, Baseband, Twisted Pair
• BPS — bits per second
• TNX — Thanks
• PMP — Project Management Professional
• EFIS — Electronic Flight Information System
• HTTPS — HyperText Transfer Protocol Secure
• ITU — International Telecommunication Union
• CGSA — Cellular Geographic Service Area
• DAHDI — Digium/Asterisk Hardware Device Interface
• SOAP — Simple Object Access Protocol
• ATC — Advanced Technology Center
• WE — Western Electric
• DASD — Direct Access Storage Device
• RARP — Reverse Address Resolution Protocol
• DTMF — Dual-Tone MultiFrequency
• BOD — Bandwidth on Demand
• NRC — National Research Council (Canada)
• BGP — Border Gateway Protocol (routing protocol)
• VT — Virtual Terminal
• EMR — Electromagnetic Radiation
• LED — law enforcement desk; light emitting diode

• CFA — Carrier Facility Assignment
• S/D — Source/Drain
• FCA — Free Carrier Absorption
• ELINT — Electronic Intelligence Satellite
• DL — Data Link
• EFS — Encrypting File System
• SN — Service Number
• O/S — Operating System
• SATAN — Security Administrator Tool for Analyzing Networks
• MAC — Media Access Control
• MTSO — Mobile Telephone Switching Office
• LDAP — Lightweight Directory Access Protocol (pronounced Ell-dap)
• SRM — Scalable Reliable Multicast
• SQ — Service Quality
• ITP — Interactive Telecommunications Program
• STD — Subscriber Trunk Dialing
• TCSEC — Trusted Computer System Evaluation Criteria
• RACF — Resource Access Control Facility
• SNR — Signal-to-Noise Ratio
• DPL — Digital Power Line
• CQA — Certified Quality Auditor
• BSS — Base Station Subsystem
• ESTEC — European Space Research and Technology Centre
• PRI — Primary Rate Interface (ISDN)
• ISM — Industrial, Scientific and Medical
• MV — Motion Vector
• DSTE — Digital Subscriber Terminal Equipment
• M-CSI — Mobility management CAMEL (Customized Applications for Mobile network Enhanced Logic) Subscription Information
• CRM — Customer Relationship Management
• DSN — Deep Space Network - network of large antennas and communication facilities.
• JVM — Java Virtual Machine
• CB — Citizens' Band
• AAAI — American Association for Artificial Intelligence's
• WTLS — Wireless Transport Layer Security
• ROI — Return on Investment
• BPDU — Bridge Protocol Data Unit
• ASARS — Advanced Synthetic Aperture Radar System
• T-IC — T-interConnect
• WDN — Wireless Developer Network
• SLIC — Subscriber Line Interface Circuit
• CDT — Central Daylight Time
• PVD — Physical Vapor Deposition
• SLV — Satellite-Launch Vehicle
• FTTH — Fiber To The Home
• SRS — Software Requirements Specifications
• SD — Speed Dial
• AP — Action Point
• TAM — Telephone Answering Machine
• GSA — U.S. General Services Administration
• SPX — Sequenced Packet Exchange

• RDS — Rate Determining Step
• MIPS — Millions of Instructions Per Second
• ETF — Early Termination Fee
• ADCCP — Advanced Data Communications Control Procedures
• CS — Central Station
• VAZO — Violating All-Zero Octet
• CAP — Capability
• WWAN — Wireless Wide Area Network
• POP — Point Of Presence (Internet)
• O&M — Operation and Maintenance
• FXS — Foreign Exchange Subscriber
• SB — Switchboard
• HZ — cycles per second (hertz)
• SOGA — Share of Gross Adds
• DID — direct inward dial
• OSCAR — Orbiting Satellite Carrying Amateur Radio
• COM — Comedy Central
• PPP — Point-to-Point Protocol
• TSE — Toronto Stock Exchange
• PDT — Portable Data Terminal
• JIT — Just in time
• RAID — Redundant Array of Inexpensive Disks
• CI — Common Interface
• CPC — Continous Packet Compression
• CBWFQ — Class Based Weighted Fair Queueing
• FIPS — Federal Information Processing Standard
• DM — Domain Model
• CSC — Common Signaling Channel
• CAPS — Call Attempts Per Second
• ACLR — Adjacent Channel Leakage Ratio
• RP — Reference Point
• DNIS — Dialed Number Identification Service
• CTU — Central Terminal Unit
• CRC — Contrôle de Redondance Cyclique (French: Cyclic Redundancy Check)
• CPN — Cisco Powered Network
• DDE — Dynamic Data Exchange (in software parlance)
• NIST — National Institute of Standards and Technology
• AQL — Acceptable Quality Level
• ASP — Application Service Provider
• MX — Mixer
• MTU — Maximum Transmission Unit
• RTU — Remote Terminal Unit
• OSTP — Office of Science and Technology Policy
• LD — Laser Diode
• C — Collector
• DMI — Distributed Management Interface
• FRS — Frame Relay Service
• VG — Voice Grade
• ASI — Asynchronous Serial Interface
• ENIAC — Electronic Numerical Integrator And Computer

• MIDP — Mobile Information Device Profile
• MLP — Mobile Location Protocol
• DTN — Data Transfer Network
• P — Priority
• SSRC — Synchronization Source
• NMR — Nuclear Magnetic Resonance
• COPS — Common Open Policy Service
• BTC — Botswana Telecommunications Corporation
• CDA — Command and Data Acquisition
• VTC — Video Teleconference
• CLI — Command line Interface (Cabletron)
• GMRS — General Mobile Radio Service
• AC — Area Code
• NPA — Numbering Plan Area
• WLAN — Wireless Local Area Network
• CIS — Computer and Information Science
• DID — data item description
• SG — Signaling Gateway (IETF)
• BSS — Base Station System
• KBYTE — Kilobyte (103)
• SIA — Securities Industry Association
• DII — Dynamic Invocation Interface
• QPSK — aeronautical quadrature phase shift keying
• CT — Computer Terminal
• EECM — End-to-End Call Manager
• FAS — Frame Alignment Signal
• E — Electra
• NES — Network Encryption System
• RTC — Real-Time Control
• SIC — Standard Industrial Classification (Code)
• SAE — Society of Automotive Engineers
• PCM — Pulse-Code Modulation
• PM — post meridian
• DCN — Design Change Notification
• SPIN — Service Provider Identification Number
• SCADA — Supervisory Control And Data Aquisition
• AFM — Atomic Force Microscopy
• MME — Mobility Management Entity
• DC — Device Control
• MIB — Management Information Base (ATM)
• BMS — Business Management System
• ER — Extended Range
• SM — Service Module
• ISAS — Institute of Space and Astronautical Sciences (Japan)
• MDM — Mobile Device Management
• AYT — Are You There
• 3G — Third Generation mobile phone network
• SDU — Signal Distribution Unit
• MH — Message Handler
• CS-PDU — Convergence Sublayer - Protocol Data Unit

• CIP — Carrier Identification Parameter
• TOS — Temporarily Out of Service
• CRO — Central Records Office
• WAR — Weekly Activity Report
• BAN — Base Area Network
• ERP — Enterprise Resource Planning
• DLL — Dynamic Link Library (computer file)
• WAYP — White and Yellow Pages
• SCU — System Control Unit
• CP — Call Processing
• ARIN — American Registry for Internet Numbers
• EDD — Envelope Delay Distortion
• TCO — Total Cost of Ownership
• XPS — X-Ray Photoelectron Spectroscopy
• EMC — Electromagnetic Compatibility
• ABN — Abnormal
• AWT — Agence Wallonne des Télécommunications
• ES — Emergency Service
• PKI — Public Key Infrastructure (cryptography)
• EEG — Electro-EncephaloGram
• ACP — Access Control Point
• IRC — International Record Carrier
• DSP — Digital Signal Processor
• CGA — Carrier Group Alarm
• NTP — Network Time Protocol
• POTS — Plain Old Telephone Service (FCW)
• EAI — Enterprise Application Integration
• TDM — Time Division Multiplexer
• SSM — Synchronization Status Message
• ACF — Access Control Field
• EU — End User
• BJT — Bipolar Junction Transistor
• CGA — Color Graphics Adapter
• EDP — Electronic Data Processing Plc (London Stock Exchange [LSE])
• REPT — Report
• NCSC — National Computer Security Center (NSA)
• IMP — Interface Message Processor
• V — Variable
• PSS — Performance Support System
• BIS — Business Information System
• SSM — Spread Spectrum Modulation
• DRM — Digital Rights Management
• EEA — European Economic Area
• ASD — Alternative Service Delivery
• NTIA — National Telecommunications and Information Administration
• AIF — Audio Interchange Format
• SN — Stock Number
• ASDE — Airport Surface Detection Equipment
• ST — Such That
• ACO — Additional Call Offering

• BIU — Bus Interface Unit
• TUR — Trunk Utilization Report
• LASA — Large Aperture Seismic Array
• TOA — Time Of Arrival
• 10BASE-T — 10 Megabits per second, Baseband, Twisted pair
• PU — Physical Unit (IBM)
• TAX — Trunk Automatic Exchange
• OLE — Object Linking and Embedding (Microsoft communication protocol)
• CE — Channel Element
• SDLC — Synchronous Data Link Control
• RDF — Radio Direction Finder
• OSP — Outside Plant
• NBS — National Bureau of Standards (US)
• ECMA — European Computer Manufacturer's Association
• DAP — Distributed Array Processor
• ODBC — Open Database Connectivity
• ECPA — Electronic Communications Privacy Act 1986
• CMP — Connection Management Protocol
• AN — Access Node
• TRS — Telecommunications Relay Service
• VOIP — Voice Over IP (Internet Protocol)
• ARINC — Aeronautical Radio Incorporated
• DDU — Disk Drive Unit
• ARQ — Automatic Repeat-reQuest
• EHF — Extremely High Frequency
• MDF — Main Distribution Frame
• SAF — System Access Fee
• ADC — Administration Center
• IAT — Integrated Access Terminal
• FCC — Federal Communications Commission (US)
• TELECOMMUTE — Telecommuting
• VC-ATOD — Virtual Clearinghouse on Alcohol, Tobacco and Other Drugs
• SABGW — System Architecture Evolution Gateway
• GI — Graded-Index
• DGPT — Directorate General of Posts and Telecommunications
• IOC — Inter-Office Channel
• TTY — Teletype Telex Machine
• FLM — First Line Maintenance
• IPM — Inches Per Minute
• CMM — Capability Maturity Model
• DHD — Dial Home Device
• FASB — Financial Accounting Standards Board
• PMT — Program Management Team
• PIM — Personal Information Manager
• FR PVC — Frame Relay Permanent Virtual Connection
• STA — State
• MTS — Message Transfer System
• CFD — Call For Discussion
• LS — Loop Start
• BA — Behaviour Aggregate

• SBU — Strategic Business Units
• ADN — Abbreviated Dialing Number
• ET — Electronic Transmission
• PVC — Permanent Virtual Connection
• AIT — Automatic Identification Technology
• AWG — American Wire Gauge
• UTC — Coordinated Universal Time
• E&M — ear and mouth (special signaling leads)
• TOVS — TIROS Operational Vertical Sounder
• DTI — Department of Trade and Industry (UK)
• DL — Definition List
• SPA — Software Publishers Association
• MA — Maintenance Action
• KHZ — kilohertz (1000 cycles per second)
• T — Temperature
• CMS — Content Management System
• AT&T — American Telephone and Telegraph (U.S. company, also known as "Ma Bell")
• PCI — Personal Computer Interface
• NF — Noise Factor
• EPR — Ethylene-Propylene Rubber
• CMRS — Commercial Mobile Radio Service
• PAP — Password Authentication Protocol (ATM)
• DM — Differential Mode
• BOSS — Binary Object Storage System
• RAN — Radio Access Network
• DPL — Digital Private-Line
• BRI — Basic Rate Interface
• B3G — Beyond Third Generation
• INSAT — Indian National Satellite
• IRS — Inertial Reference System
• SML/SMS — Service Management Layer/Service Management Service
• CP — Change Proposal
• RSN — Real Soon Now [which may be a long time coming]
• PDN — Packet Data Network
• ADT — American District Telegraph Company
• CONUS — Contiguous United States
• MPI — Minimum Picture Interval
• IEC — Interexchange Carrier
• BIOS — Basic Input Output System
• SWAP — Shared Wireless Access Protocol
• DTAP — Direct Transfer Application Process
• CST — Central Standard Time (UTC-6 Hours)
• IANA — Internet Assigned Numbers Authority
• NEMA — National Electric Manufacturer's Association
• CMD — Command
• RXQUAL — Received Signal Quality
• HEHO — Head End Hop Off
• EDC — Electronic Dispersion Compensator
• ILEC — Incumbent Local Exchange Carrier
• LQR — Linear Quadratic Regulator

• ILD — International Long Distance
• PVC — Permanent Virtual Circuit (ATM)
• LDN — Local Directory Number
• ACTV — Active
• SW — South West
• COO — Cell of Origin
• PM — Project Manager
• LNP — Local Number Portability
• TL1 — Transaction Language 1
• CIP — Channel Interface Processor
• PABX — private automatic branch exchange (telephone)
• CVR — Crystal Video Receiver
• VGA — Video Graphics Array
• CCSD — command communications service designator; control communications service designator
• ALOC — Average Length Of Call
• FTTB — Fiber To The Building
• RSS — Really Simple Syndication
• CRTS — Cellular Radio Telecommunications Service
• KAK — Key-Auto-Key
• CIFS — Common Internet File System
• MP — Modulation Parameter
• CND — Calling Number Display
• AP — access point
• BCH — Binary Coded Hexadecimal
• PBX — Private Branch eXchange (company phone system)
• CAM — Common Access Method
• ESF — Edge Spread Function
• FSK — Frequency-Shift Keying
• MSW — Most Significant Word
• TSO — Telecommunications Service Order
• CHF — Swiss Franc
• MA — Message Analysis
• FOD — Fax on Demand
• SDM — Service Delivery Management
• OTDOA — Observed Time Difference of Arrival
• PPARC — Particle Physics and Astronomy Research Council
• FOSE — Federal Office Systems Exposition
• PP — Polypropylene
• KB — Kilobyte: One thousand and twenty-four bytes kbps kilo bit per second
• APS — Automatic Protection Switching (SONET/SDH)
• AOL — America on line
• 100BASE-T4 — 100 Megabits per Second, Baseband, Four-pair Category 3 UTP cables
• WFA — Wait for Answer
• AOS — Alternate Operator Service
• ACAP — Application Configuration Access Protocol
• EIGRP — Enhanced Interior Gateway Routing Protocol
• COT — Central Office Terminal
• TCIC — Trunk Circuit Identification Code
• AVR — Automated Voice Response
• ISOC — Internet Society

• CIC — Carrier Identification Code
• ORB — Object Request Broker
• RDT — Recall Dial Tone
• FAX — Facsimile
• PM — Phase Modulation
• CFO — Communication Filing Officer
• ADT — Atlantic Daylight Time (UTC-3 Hours)
• BOFH — Bastard Operator From Hell
• CFD — computational fluid dynamics
• WPAN — Wireless Personal Area Network
• LANE — Local Area Network Emulation
• EGP — Exterior Gateway Protocol
• CRV — Call Reference Value
• SDH — Synchronous Digital Hierarchy (ATM)
• OML — Object Model Library
• RMI — Remote Method Invocation
• ROTFL — Roll On The Floor Laughing
• RSL — Restricted Service License
• ICL — Inserted Connection Loss
• B2C — Business-to-Consumer
• IMC — Intermediate Metal Conduit
• SN — Switching Network
• ASA — Acoustical Society of America
• MR — Mobile Router
• FGA — Feature Group A
• OC-9 — Optical Carrier Signal, Level 9
• CFV — Call For Vote(s)
• FGD — Feature Group D
• DTI — Digital Trunk Interface
• RAU — Remote Access Unit
• SIT — Static Induction Transistor
• DCA — Dynamic Channel Assignment
• CCP — Compression Control Protocol
• CPC — Calling Party Control
• IPS — InPlane Switching
• USA — Underground Service Alert
• NTIS — National Technical Information Service Technology Administration
• EMR — Electromechanical Relay
• IRS — Interface Requirements Specification
• DSI — Digital Speech Interpolation
• LOO — Likelihood of Occurrence
• CLM — Career Limiting Move. A reminder to think twice before embarking on any action that has an obvious whiff of disaster about it. (Ack R Gesling and S Phillips)
• SMS — Service Management System
• SIL — Solid Immersion Lens
• SIM — Subscriber Identification Module
• RNX — Restricted Numeric eXchange
• GAN — Global Area Network
• CCCH — Common Control Channel
• DCE — Data Communication Equipment
• UN — United Narions

• SVP — Senior Vice President
• CGM — Computer Graphics Metafile
• WIPO — World Intellectual Property Organization
• HVAC — Heating, Ventilation, and Air Conditioning
• C4 — Command, Control, Communications, and Computers
• RPM — Resale Price Maintenance. The UK Net Book Agreement, as was. Means by which retail prices are controlled by primary suppliers. (Alternatively, Revolutions Per Minute, as in engine speed and 78, 33 and 45 records. In years to come how many people will know
• PACS — Personal Access Communications System
• DNIC — Data Network Identification Code
• MC — Maintenance Control
• DMS — Data Management System
• WHT — Walsh-Hadamard Transform
• RSVP — Resource Reservation Protocol (Internet)
• VN — Virtual Network
• FDI — Feeder Distribution Interface
• SDK — Software Development Kit (Microsoft)
• DVB — Digital Video Broadcasting
• NSS — Network Switching Subsystem
• CMA — Communications Management Association
• MIT — Massachusetts Institute of Technology (U.S.)
• TT — Text-Telephone
• BAN — Building Area Network
• CSPDN — Circuit Switched Public Data Network
• FI — Format Identifier
• WAIS — Wide Area Information Server
• ATS — Abstract Test Suite
• CORBA — Common Object Request Broker Architecture
• FITL — Fiber-In-The-Loop
• ADC — Access Deficit Charge
• CG — Center of Gravity (DXS)
• AIFF — Audio Interchange File Format
• SSN — Switched Service Network
• CDM — Conceptual Data Model
• FAC — Forced Authorization Code
• VPA — Valid Peripheral Address
• OC-18 — Optical Carrier Signal, Level 18
• VOC — Volatile Organic Compounds (air pollution)
• DSLAM — Digital Subscriber Line Access Multiplexer (Module)
• MMU — Memory Management Unit
• VF — Voice Frequency
• NC — Network Channel
• ECM — Electronic Counter Measures
• SHA — Secure Hash Algorithm
• SPD — Serial Presence Detect
• RICK — Repeater Interface Communications Kit
• CCD — Charge Coupled Device - a device for the movement of electrical charge.
• AAV — Accountholder Authentication Value
• EC — European Community
• JPEG — Joint Photographic Experts Group (24-bit image storage format)
• NIST — National Institute of Standards & Technology (US)
• RP — Radio Port

• SCPC — single channel per carrier
• COC — Central Office Connection
• AVL — Available
• ISAKMP — Internet Security Association and Key Management Protocol
• IR — International Roaming
• DTD — Document Type Definition (XML)
• VSAT — Very Small Aperture Terminal (satellite service)
• RRN — Routing Recording Number
• 100BASE-T — 100 Megabits per second, Baseband, Twisted pair
• BSA — Business Software Alliance
• TU — Transmission Unit
• SAR — synthetic aperture radar (satellite)
• EMCON — Electromagnetic Emission Control
• CSR — Customer Service Report
• HSS — Home Subscriber Server
• BT — Burst Tolerance
• ESP — Encapsulating Security Payload
• RCU — Radio Control Unit
• EBS — Electron Bombarded Silicon
• CDE — Common Desktop Environment
• DPA — Distributed-Power Architecture
• TDMA — Time Division Multiple Access
• TCB — Telecommunication Certification Body
• TD — Transmit Data
• UI — User Interface
• FC — Frame Control
• SRR — Search and Rescue Region
• ANI — Automatic Number Identification (Caller ID)
• UPS — Uninterruptible Power Supply
• RCC — Radio Common Carrier
• RMS — root mean square (preferred over "RMS")
• BMEWS — Ballistic Missile Early Warning System (bee-mews)
• NRPB — National Radiological Protection Board
• MLM — Multi-Longitudinal Mode
• DDN — U.S. Defense Data Network
• MGMT — Management
• DEMUX — Demultiplexer
• OT — Office of Telecommunications
• WPM — speech--words per minute
• ELT — Emergency Locator Transmitter
• SCM — Supply Chain Management
• WVOIP — Wireless Voice over Internet Protocol
• LISP — List Processing Language
• EEROM — Electronically Erasable Read-Only Memory
• NOC — Network Operations Center
• BUS — Business
• T&C — Terms & Conditions
• LIF — Logical Interchange Format
• B2B — Business to Businesse
• ISSN — International Standard Serial Number (ISO 3297)

• ADB — Apple Desktop Bus
• ADM — Administration Building
• ISG — Information Systems Group
• CV — Coding Violation
• ALB — Analog Loopback
• CLK — Clock
• DSS — Digital Signature Standard
• EOB — End Of Business
• HDSL — High-bit-rate Digital Subscriber Line
• VPI — Virtual Path Identifier
• 1FB — Single line, Flat Business rate;
• IG — Interface Group
• YYP — Yahoo Yellow Pages
• CLETS — California Law Enforcement Telecommunication System
• MPEG — Motion Picture Experts Group
• FEP — Front End Processor
• DDI — Direct Dialing Incoming
• CRS — Cell Relay Service
• HTML — Hyper Text Markup Language
• TDOA — Time Difference Of Arrival
• TC — Transmission Convergence (ATM)
• NIU — Network Interface Unit
• DER — Distinguished Encoding Rules
• DVMRP — Distance Vector Multicast Routing Protocol
• TSC — Test System Controller
• BSC — Bi-Synchronous Communications
• BCH — Bose-Chaudhuri-Hocquenghem Coding
• GBT — Ground Based Tower
• EIA — Extended Interaction Amplifier
• ACPI — Advanced Configuration and Power Interface
• ISI — Intersymbol Interference
• INTELSAT — International Telecommunications Satellite
• IAB — Internet Architecture Board
• C³CM — Command, Control and Communications Countermeasures
• COAX — Coaxial
• PD — Pulse Duration
• CAL — Calorie
• OMF — Object Management Framework
• NAT — Network Address Translation
• APPL — Application
• ULL — Unbundled Local Loop
• L2TPV3 — Layer 2 Tunneling Protocol Version 3
• GHZ — Gigahertz
• DS-0 — Digital Signal, Level 0
• CSPRM — Common Signaling Protocols Resource Module
• ACA — Adaptive Channel Allocation
• VSAT — Very Small-Aperture Terminal
• GDM — GSM (Global System for Mobile communications) Data Module
• ISBN — International Standard Book Number (ISO 2108)
• JRE — Java Runtime Environment

• DAT — Digital Audio Tape
• MBPS — Megabits per second
• WDA — Wireless Digital Assistant
• OMP — Open Management Platform
• DIBL — Drain-induced Barrier Lowering
• FEC — Forward Error Correction
• ARM — Asynchronous Response Mode
• LATA — Local Access and Transport Area
• INE — Intelligent Network Element
• AT — Attenuation
• SSP — Security Service Provider
• RMON — Remote Monitoring
• BLER — Block Error Rate
• IPS — Instructions Per Second
• PROM — Programmable Read-Only Memory
• SOS — Save Our Souls (Help!)
• SPGA — Staggered Pin Grid Array
• TOMS — Total Ozone Mapping Spectrometer (satellite Instrument)
• CAD — Computer-Aided Design
• FCA — Fixed Channel Allocation
• BFI — Brute Force and Ignorance. An expression found in everyday language since the early 1900s, meaning a heavy handed unrefined solution to a problem (especially fixing something - like bashing an electrical appliance to get it working again). In more recent
• ALT — Accelerated Life Test
• LI — Length Indicator
• TCA — Threshold Crossing Alert
• DLP — Data Link Processor
• CES — Consumer Electronics Show
• CBR — Constant Bit Rate
• VTS — Vessel Traffic Service
• CACH — Call Appearance Call Handling
• WTS — Wireless Telecommunications Symposium
• BIS — Brought Into Service
• EISA — Extended Industry Standard Architecture
• QDR — Quad Data Rate
• TAG — Technical Advisory Group for Biological Control Agents of Weeds
• DNS — Domain Name Service
• ESCON — Enterprise System Connection
• FEP — Front-End Processor
• GS — Ground Start
• COMDEX — Computer Dealers Exposition
• OFC — Office
• TP — Telephone Pole
• OC-256 — Optical Carrier Signal, Level 256
• NDVI — Normalized Difference Vegetation Index
• APDU — Application Protocol Data Units
• SDP — Software Development Plan
• DSCP — Differentiated Services Code Point
• RFR — Radio Frequency Radiation
• DPT — Dynamic Packet Transport
• LIDB — Line Information DataBase
• MMM — Mobile Media Mode

• YA — Yet Another
• TKIP — Temporal Key Integrity Protocol
• DN — Distinguished Name
• EULA — End User License Agreement (usually in reference to software)
• KDC — Kerberos Key Distribution Center
• LCF — Location Confirm
• JCL — Job Control Language
• AWACS — Airborne Warning And Control System
• CPS — characters per second
• SAT — Satellite
• PDL — Positioning Data Link
• MIME — Multipurpose Internet Mail Extension
• SISIR — Singapore Institute of Standards and Industrial Research
• DPDU — Data Protocol Data Unit
• VMS — Virtual Memory System
• EMS — Element Management System (ATM)
• 2G — Second generation cellular
• MGC — Multimedia Gateway Controller
• EMF — Event Management Framework
• EDFA — Erbium-Doped Fiber Amplifier
• OOP — Object-Oriented Programming
• SCM — Single-Carrier Modulation
• FDTD — Finite Difference Time Domain
• NCF — Network Control Facility
• LRC — Learning Resource Center
• WAE — Wireless Application Environment
• SCR — System Change Request
• IRQ — Interrupt Request
• EDT — Eastern Daylight Time
• 911 — Emergency Services Phone Number
• CLDC — Connected Limited Device Configuration
• JDK — Java Development Kit
• RDI — Remote Defect Indicator (UNI Fault Management)
• DUA — Directory User Agent
• FAT — File Allocation Table
• VR — Virtual Router
• ANC — Access Network Controller
• BSI — British Standards Institution
• DE — Discard Eligibility (ATM)
• IMEI — International Mobile Equipment Identity
• D-RAM — Dynamic Random Access Memory
• CFNRY — Call Forwarding on No Reply
• TDD — Time Division Duplex
• USGS — United States Geological Survey (DOI)
• RTC — Right to Carry
• UCF — Unregistration Confirm
• DIL — Direct Inward Line
• OSS — Operations Support System
• EVA — Electronic Video Agent
• EMS — Express Mail Service

• FNN — Full National Number
• CAPTAIN — Character And Pattern Telephone Access Information Network
• FWA — Fixed Wireless Access
• ACC — Area Control Center
• HEX — Hexadecimal (base 16)
• VNS — Virtual Network System
• QI — Quality Indicator
• DDD — Direct Distance Dialing
• MF — Multiple Frequency
• WMO — World Meteorological Organization (ICSU)
• UMTS — Universal Mobile Telecommunications Service
• SSMA — Spread-Spectrum Multiple Access
• SCR — Sustainable Cell Rate
• TCC — Transmission Control Code
• 3GPP — Third Generation Partnership Project
• CID — Craft Interface Device
• MBWA — Mobile Broadband Wireless Access
• CSO — Customer Service Operations
• IP — Intellectual Property
• EFT — Electronic Funds Transfer
• CHTML — Compact Hypertext Markup Language
• TP — Transition Point
• DA — deca
• CNG — Fax Calling Tone
• CLD — Cross-Layer Design
• RCP — Right-Hand Circular Polarization
• QS — Quasi-Synchronous
• DTE — Digital Terminal Equipment
• TEI — Terminal Endpoint Identifier
• ETN — Electronic Tandem Network
• LB — Local Battery
• DARTS — Design Approach for Real-Time Systems
• UMA — Unlicensed Mobile Access
• LSW — Least Significant Word
• LH — Link Handler
• B-ISDN — Broadband Integrated Services Digital Network
• WAP — Wireless Application Protocol
• SRL — Singing Return Loss
• RADIUS — Remote Authentication Dial-In User Service
• COMINT — Communications Intelligence
• LCP — Local Control Point
• MSDP — Multicast Source Discovery Protocol
• VBA — Visual BASIC for Applications
• CPAP — Customer Premises Access Profile
• PCCA — Portable Computer Communications Association
• MFC — Multi-Frequency Code
• UART — Universal Asynchronous Receiver/Transmitter
• STMR — Sidetone Masking Rating (telecommunications)
• VPX — Virtual Path Cross-Connect
• LMS — Learning management system

• ASAR — Advanced Synthetic Aperture Radar 
• AWG — arrayed waveguide grating
• CTO — Commonwealth Telecommunications Organisation
• CRLF — Carriage-Return Line-Feed
• SE — Southeast
• EA — Extended Address Field Bit
• CCR — Customer Controlled Reconfiguration (Sprint)
• TNI — Telephone Network Interface
• OBC — Onboard Computer
• RISC — Reduced Instruction Set Computing
• DOD — Dial on Demand
• LRC — Longitudinal Redundancy Check
• FTTC — Fiber To The Curb光纤到路边
• CON — Concentrator
• CT — Cordless Telecommunications
• FR — Functional Requirement
• KM — Knowledge Management
• FMR — Follow Me Roaming
• CIS — Center for Integrated Systems
• OSF — Open Software Foundation
• NRP — Network Resource Planning
• ABBR — Abbreviation
• CPOP — Circuit Precedence Over Packet data
• CRIS — Carrier Route Information System
• RGN — Region
• ECS — Encryption Control Signal
• BP — Block Parity
• WARC — World Administrative Radio Conference
• P&A — Privacy and Authentication
• EBCDIC — Extended Binary-Coded Decimal Interchange Code
• DII — Defense Information Infrastructure
• IAD — Integrated Access Device
• CPG — Converged Packet Gateway
• TP — Termination Point
• POP — Post Office Protocol
• 2W — Two Wire
• SPID — Service Profile Identifier
• BLOS — Beyond Line-Of-Sight
• VCI — Virtual Channel Identifier
• SCC — Specialized Common Carrier
• FEA — Finite Element Analysis
• EIR — Equipment Identity Register
• CRBT — Caller Ring Back Tone
• CIAC — Computer Incident Advisory Capability
• SMB — Server Message Block
• RAD — Recorded Announcement Device
• TFTP — Trivial File Transfer Protocol (ATM)
• HSPA — High Speed Packet Access
• HDML — Handheld Device Markup Language
• TED — Triteal Enterprise Desktop

• AMPS — Advanced Mobile Phone System
• B6ZS — Bipolar 6 Zero Substitution
• CSCW — Computer-Supported Cooperative Work
• RJE — Remote Job Entry
• DCS — Data Collection System (NOAA Polar Orbiting Satellites)
• EBIC — Electron Beam Induced Current
• FEXT — Far-End Cross Talk
• PCMCIA — Personal Computer Memory Card International Association
• OD — Outside Diameter
• BCDIC — Binary Coded Decimal Interchange Code
• CSP — Converged Service Platform
• WFA — Work Force Administration
• VBR — Variable Bit Rate (ATM)
• ICANN — Internet Corporation for Assigned Names and Numbers
• EST — Establish
• MHO — My Humble Opinion
• ASN.1 — Abstract Syntax Notation One
• RSS — Radio Service Software (Motorola)
• MCC — Mission Control Center (JSC)
• DXC — Digital Cross Connect
• SNA — System Network Architecture
• WIN — Wireless Intelligent Network
• DSN — Defense Switched Network
• YABA — Yet Another Bloody Acronym
• DOD — Direct Outward Dialing
• CMIP — Common Management Information Protocol (ATM)
• ET — Exchange Terminal
• HLR — Home Location Register
• PNP — Plug-and-Play
• IPCP — Internet Protocol Control Protocol
• ABM — Asynchronous Balanced Mode
• ECM — Error Correction Model
• WINS — Windows Internet Name Service
• FTTK — Fibre To The Kerb
• VOB — Versioned Object Base
• WTL — Wireless Transport Layer
• IRDA — Infrared Data Association
• TRS — Trunked Radio Systems
• CTE — Computer Telephony Engineer
• IEEE — Institute of Electrical and Electronics Engineers
• WSFL — Web Services Flow Language
• DIV — Divisionsion
• LXT — Local Exchange Terminal
• RDBMS — Relational Data Base Management System (Oracle)
• DRQ — Disengage Request
• OTA — Office of Technology Assessment (U.S.; abolished by Congress, Fall 1995)
• SCE — Service Creation Environment
• RSS — root-sum-square
• RDT — Remote Digital Terminal
• RMS — Resource Management System

• VLAN — Virtual Local Area Network
• CALEA — Communications Assistance for Law Enforcement Act
• HFC — Hybrid Fiber/Coaxial network
• RQMT — Requirement
• VLSI — Very-Large-Scale Integration
• BER — Basic Encoding Rules (ASN.1)
• TBCD — Telephony Binary Coded Decimal
• FMS — Fixed Mobile Substitution
• PST — Pacific Standard Time (UTC-8 Hours)
• AMOLED — Active Matrix Organic Light-Emitting Diode
• GLT — Great Lakes Telecom
• WSDL — Web Services Description Language
• VPWS — Virtual Private Wire Service
• OSHA — Occupational Safety and Health Act (1970)
• DDM — Data Distribution Manager
• LCR — Least Cost Routing
• PJC — Pointer Justification Count
• RDMA — Remote Direct Memory Access
• CIRC — Cross-Interleaved Reed-Solomon Code
• FH — Frequency Hopping
• ASN.1 — Abstract Syntax Notation 1
• DFG — difference-frequency generation
• TCM — Time Compression Multiplexer
• TLT — Test Loop Translator
• AFOSR — Air Force Office Of Scientific Research(USA)
• CM — Connection Manager
• FECN — Forward Explicit Congestion Notification (ATM)
• JST — Japan Standard Time
• RLU — Remote Line Unit
• VCA — Voice Connecting Arrangement
• LRQ — Location Request
• AAP — Alternate Access Provider
• CAVE — Cellular Authentication and Voice Encryption Algorithm
• CD — Critical Dimension
• IMSI — International Mobile Subscriber Identity
• SPC — Statistical Process Control. Forerunning quality theory from the 1960s to TQC and TQM.
• CDM — Configuration Data Manager
• SIGTRAN — Signaling Transport
• EM — Element Manager
• SITA — Société Internationale de Télécommunications Aéronautiques
• DDSN — Digital Derived Services Network
• VHSIC — Very High-Speed Integrated Circuit
• ROS — Return on Sales
• DDCMP — Digital Data Communications Message Protocol
• CPH — Call Party Handling
• CC — Composite Clock (SONET)
• LAG — Link Aggregation Group
• HPN — Home Phone Network
• UTL — Utility
• WTO — World Trade Organisation

• ADF — automatic document feeder
• LMS — Location and Monitoring Service
• NII — National Information Infrastructure (USA)
• VO — Voice Only
• AMPS — Advanced Mobile Phone Service (cellular phone standard)
• BY — Busy
• PSN — Packet Switched Network
• SMDS — Switched Multimegabit Data Service (ATM)
• FPS — Framing Pattern Sequence
• LVM — Line Verification Module
• TOC — Telecommunication Operations Center
• VSC — Vertical Service Code
• BHCA — Busy Hour Call Attempt
• VQV — Voice Quality Value
• VLF — Vertical-Laminar-Flow
• BSID — Base Station Identity
• CTIA — Cellular Telecommunications Industry Association
• NAS — Network-Attached Storage
• APN — An Access Point Name
• TP — Transaction Processor
• CMOS — Complementary Metal Oxide Semiconductors
• DPSK — Differential Phase Shift Keying
• X — X Window System
• PM — Processable Mode
• PTT — Push to Talk Technology
• VLSI — Very Large-Scale Integration
• SUS — Suspension
• ALI — Automatic Location Information
• NDS — Novell Directory Services
• CAMA — Centralized Automatic Message Accounting
• 4W — Four-Wire
• RADIUS — Remote Authentication dial In User Service
• DQDB — Distributed Queue Dual Bus
• 4G — Fourth Generation Wireless Systems
• CRB — Cramer-Rao Bound
• ACSE — Association Control Service Element
• DDU — Digital Data Unit
• SPA — Special Prorate Agreement
• DCAS — Downloadable Conditional Access System
• OSA — Open System Architecture
• NAFTA — North American Free Trade Agreement
• IWF — Interworking Function
• TCS — Telephony Control Specification
• UML — Unified Modeling Language (Object Management Group, OMG)
• TEL — Telephone
• EDSX — Electronic Digital Signal Cross-Connect
• CLCC — Ceramic Leaded Chip Carrier
• ASQ — Alpha System Qualification
• SMI — Structure of Management Information
• BAM — Basic Access Module

• TTYL — Type To You Later
• POE — power over ethernetinjector
• CPT — Cellular Paging Teleservice
• VCR — Videocassette Recorder
• TACSAT — Tactical Satellite
• MB — Measured Business
• OWS — Operator Work Station
• 2G — Second Generation Wireless Systems
• CMT — Commercial Metering Transponder
• CBEMA — Computer & Business Equipment Manufacturers Association
• NE — Network Element
• NFPA — National Fire Protection Association
• RPV — Remotely Piloted Vehicle
• BIND — Berkeley Internet Name Domain
• SMSC — Short Message Service Center
• PY — person-year
• DPCM — differential pulse code modulation
• EFCI — Explicit Forward Congestion Indication (ATM)
• BPP — Billed Party Preference
• ACF — Advanced Communications Function (IBM)
• UCM — Use Case Map
• LP — Line Pair
• CC — Country Code
• ESA — Enhanced Subscriber Authentication
• LIM — Line Isolation Monitor
• SMU — Service Management Unit
• CCIR — International Radio Consultative Committee (French Acronym)
• ATB — Above-Ground Telecommunications Backbone
• LIS — Lightning Imaging Sensor
• CCNA — Cisco Certified Network Associated
• OXCO — Oven-Controlled Crystal Oscillator
• PEM — Privacy-Enhanced Mail
• LLA — Link Level Access
• WAR — Wireless Access Revolution
• CCITT — Comit? Consultatif International T?l?graphique et T?l?phonique
• RBS — Robbed Bit Signaling
• CODEC — Coder/decoder
• STP — standard temperature and pressure (0° and 1 atm)
• SLAM — Scanning Laser Acoustic Microscope
• IBSS — Independent Basic Service Set
• DAF — Directory Access Function
• AMP — amplifier / amplification
• BNC — Bayonet Neill-Concelman
• NTDS — Naval Tactical Data System
• AI — Adapter Interface
• SIO — Service Information Octet
• PTP — Point To point Protocol
• EMI — Electro-Magnetic Interference
• GDK — GIMP (GNU Image Manipulation Program) Drawing Kit
• DCF — Distributed Coordination Function

• BC — Basic Call
• PSDN — Public Switched Digital Network
• DIS — Draft International Standard
• ANAC — An Automatic Number Announcement Circuit
• SR — Scanning Radiometer
• CES — Circuit Emulation Service
• ECE — Economische Commissie voor Europa (United Nations) (Dutch: Economic Commission for Europe)
• TPS — Telephone Preference Service
• TBPS — Terabits Per Second
• NMS — NetWare Management System
• PARC — Palo Alto Research Center
• LDP — Label Distribution Protocol
• C3I — Command, Control, Communications & Intelligence
• 4GL — Fourth-Generation Language
• KSU — Key Service Unit
• WORM — Write-Once, Read-Many
• FMC — Fixed Mobile Convergence "Mobile UC or Unified Communications over Wireless"
• CCNA — Cisco Certified Network Administrator
• 3G — Third Generation (mobile communication system)
• AAV — Alternate Access Vendor
• DECCO — DISA Defense Commercial Communications Office
• DRFM — Digital Radio-Frequency Memory
• DNSIX — Defense Network Security Information Exchange
• 2W — 2-Wire
• YAHOO — You Are Hazy Over Oranges
• TSR — Terabit Switch/Router
• RECON — Reconnaissance
• SCH — Synchronization Channel
• DCMI — Dublin Core Metadata Initiative (Online Computer Library Center)
• AUI — Attachment Unit Interface
• BOM — Bit-Oriented Message
• JTF — Joint Task Force
• AAS — advanced automation system (FAA)
• ECR — Electronic Cash Register
• CQ — Communications Quality
• MAG — Mobile Access Gateway
• APPC — Advanced Program-to Program Communications
• AMSS — Automatic Message Switching System
• BASIZE — Buffer Allocation Size
• MAC — Message Authenticity Check
• SIP — Session Initiation Protocol
• ACF — Access Coordination Function
• ESCA — photoelectron spectroscopy for chemical analysis
• LBR — Low Bit Rate
• VDR — Voice Digitization Rate
• ADPC — Automatic Data Processing Center
• PLE — Path Length Efficiency
• BSS — Broadband Switching System
• SMPTE — Society of Motion Picture and Television Engineers, Inc.
• DTU — Data Transfer Unit

• AMTFT — Active Matrix Thin Film Transistor
• ISC — International Switching Center
• TACS — Total Access Cellular System
• LEC — Local Exchange Carrier
• DAC — Digital-To-Analog Converter
• NIMBY — Not In My Back Yard
• IPLC — International Private Leased Circuit
• IRTF — Internet Research Task Force
• SVC — Switched Virtual Circuit (ATM)
• SQL — Specified Quality Level
• FM — frequency modulation
• VCC — Virtual Channel Connection (ATM)
• CGI — Cell Global Identity
• DLL — Digital Local Line
• EVC — Electronic Voucher Charging
• LSC — Link State Control
• GTB — Global Telecom Brokers
• CNG — comfort noise generation
• DOCSIS — Data over Cable Service Interface Specification
• RACH — Random Access Channel
• VSAM — Virtual Storage Access Method
• STU — Secure Telephone Unit
• TIFF — Tag Image File Format
• TTY — Text Teletype
• ECP — Engineering Change Proposals
• DXF — Data Exchange Format
• BDE — Borland Database Engine
• SONET — Synchronous Optical Network
• BELLCORE — Bell Communications Research, Inc.
• ACT — ACTIVITY, ACTIVITIES
• PLL — Phase Locked Loop
• IDF — Independent Distribution Frame
• CBQ — Class-Based Queuing
• BSA — Basic Service Area
• CRBT — Color Ring Back Tone
• NOAO — National Optical Astronomy Observatories (Tucson, AZ)
• AFPS — Automatic Facility Protection Switching
• PIC — Programmable Interrupt Controller
• CBMS — Computer-Based Message System
• NE — North-East
• SSAP — Source Service Access Point
• RRC — Root Raised-Cosine
• CVD — Chemical Vapor Deposition
• IMAP — Internet Mail Access Protocol
• CCA — Carrier-Controlled Approach
• ITA — Illinois Telecommunications Association
• DPDT — Double-Pole Double-Throw
• CICS — Customer Information Control System (IBM Mainframe Software; Kicks Or C-I-C-S)
• FDD — Frequency Division Duplex
• DISN — Defense Information Systems Network

• PTP — Point to Point Transmission Service (electricity)
• PBT — Polybutylene Terephthalate
• DSCS — Defense Satellite Communication System
• TRMM — Tropical Rainfall Measuring Mission (US-Japan)
• NCP — Network Control Protocol
• ACEK — Authentication Encryption Key
• MSRN — Mobile Station Roaming Number
• CAC — Connection Admission Control (Asynchronous Transfer Mode)
• SGS — Software Generation System
• AAL5 — ATM (Asynchronous Transmission Mode) Adaptation Layer 5
• COFA — Change Of Frame Alignment
• CSP — Continuous Speech Processing
• MCP — Microsoft Certified Professional
• TDD — Telecommunications Device for the Deaf
• ASEAN — Association of South East Asian Nations
• NLM — National Library of Medicine (National Institutes of Health)
• CCITT — Comite Consultatif International Telegraphique et Telephonique (now ITU-T)
• TARP — Target Identifier Address Resolution Protocol
• NAK — Negative Acknowledge
• QOD — Quality of Data
• RIPE NCC — Reseaux IP Europeens Network Coordination Centre
• LSAP — Link Service Access Point
• SXS — Step-By-Step
• ESN — Electronic Serial Number
• TRIG — Trigger
• PTT — Push to Talk Taster
• IVP — Integrated Voice Protocol
• SS7 — Signaling System 7
• MGCP — Multimedia Gateway Control Protocol
• NSAI — National Standards Authority of Ireland
• ACM — Address Complete Message
• SES — Scientific and Engineering Software
• S/N — Signal-to-Noise ratio
• NFR — Near-Field Recording
• BPSK — Binary Phase-shift Keying
• NT — New Technology, also Windows NT
• SIMT — Système interbancaire marocain de télécompensation
• TRX — Tandem Repeater eXchange
• EV — electronvolt
• FOIP — Fax Over Internet Protocol
• TXM — Transmission X-ray Microscope
• UDT — Unreliable Data Transfer
• ARFA — Allied Radio Frequency Agency
• STN — Station
• P2P — Person-to-Person
• NCOS — Network Class Of Service
• B-ISDN — Broadband ISDN
• BT — Bluetooth Tablet
• LT — Line Termination
• RX — Receive

• AF — Assured Forwarding
• DNA — Do Not Answer
• NMC — Network Management Center
• MMS — Multimedia Message Service
• PDSO — Packet Data Security Overlay
• SWBD — Switchboard
• MAP — Mobile Application Part
• UBR — Unspecified Bit Rate
• DCO — Dial Central Office
• APS — Advanced Power System
• IOC — Interoffice Channel
• WNAP — Wireless Network Access Point
• OCC — Occupancy
• CEPT — Conférence Européenne des Administrations des Postes et des Télécommunications
• BHCC — Busy Hour Call Completions
• FCA — Free Carrier Alongside
• IR — Information Request
• EGSM — Extended Global System for Mobile Communications
• FDOA — Frequency Difference Of Arrival
• ATD — Advanced Technology Demonstration
• NREN — National Research and Education Network
• OSD — Onscreen Display
• ENV — Environment
• RAU — Radio Access Unit (Army)
• WK — Week
• UDP — Up Down Pair
• CU — Cooling Unit
• VESA — Video Electronics Standards Association
• SKU — Stockkeeping Unit
• PMT — Photo Multiplier Tube
• DS0 — Digital Signal Zero
• RCT — remote Control Terminal
• ELFEXT — Equal-Level Far-End Cross-Talk
• LN — Line
• COP — Character Oriented Protocol
• AFRINIC — African Network Information Centre
• NCSA — National Center for Supercomputing Applications
• UTP — Universal Transmission Protocol
• SDP — Session Description Protocol
• VRML — Virtual Reality Modeling Language
• RCS — Radar Cross Section
• SRS — Supported Residential Services
• PTT — Push to Talk Testing
• TCP/IP — Transmission Control/Internet Protocol
• CSIRO — Commonwealth Scientific and Industrial Research Organization
• CGI — Computer Graphics Interface
• IPRC — Intellectual Property Rights Committee
• UPT — Universal Personal Telecommunications
• LMS — Local Measured Service
• DECT — Digital Enhanced Cordless Telecommunication

• NW — North West
• CDA — Communications Decency Act's
• DCEF — Distributed Cisco Express Forwarding
• LRM — Long Reach Multimode
• USF — Universal Server Farm
• NCAR — National Center for Atmospheric Research (US)
• MPU — Main Processor Unit
• CMC — Career Management Center
• DDLD — Direct Dial Long Distance
• ATRAC — Adaptive Transform Acoustic Coding
• CS — Connection Segment
• ADCCP — Advanced Data Communication Control Procedures
• DLT — Delete
• AAS — Automatic Announcement Subsystem
• SPT — System Page Table
• MCR — Minimum Cell Rate (ATM)
• ERL — Echo Return Loss
• ATS — Automatic Transfer Switch
• CVT — Circuit Validation Test
• DOT — Department of Telecommunications (India)
• SDN — Software Defined Network
• TPF — Transmission Priority Field
• FTTP — Fiber To The Premises
• DL — Downlink Message
• DPST — Double-Pole Single-Throw
• PTM — Point-To-Multipoint
• CDV — Compressed Digital Video
• BTAM — Basic Telecommunications Access Method
• DNC — Do Not Call
• ESP — Essential Service Protection
• NSAP — Network Service Access Point
• MMSI — Maritime Mobile Service Identity
• GMSS — Global Mobile Satellite System
• LQC — Line Quality Control
• STA — Science and Technology Agency (Japan)
• FIOS — Fiber Optic Services
• FMS — Fraud Management System
• TSD — Type Specific Driver
• PIM — Protocol Independent Multicast
• VFL — Visual Fault Locator
• CCC — CDMA Cluster Controller
• DCC — Digital Control Channel
• CSI — Clearing Subnetwork Identification
• DISA — U.S. Defense Information Systems Agency
• PSQM — Perceptual Speech Quality Measure
• DTR — Down-Time Ratio
• UAT — Universal Access Transceiver
• OLS — Optical Line System
• ATIS — Automatic Transmitter Identification System
• TSGR — Transport System Generic Requirements

• CIP — Continuous Improvement Program
• HSCSWD — High-Speed Circuit-SWitched Data
• QEDI — Quod Erat Demonstrandum
• VTAM — Virtual Telecommunication Access Method
• UIH — Unnumbered Information with Header check
• AMA — automatic message accounting
• 4WAI — Four-Wire Analog Interface
• VADB — Virtual Auto Dial Backup
• DLCI — data link connection identifier
• USF — Universal Service Fund
• SPE — Synchronous Payload Envelope
• BHP — Burst Header Packet
• RJ-14 — Registered Jack type 14 (2-wire connector)
• ASTD — American Society of Training and Development (Alexandria, Virginia)
• LSI — Large Scale Integration -> VLSI
• AMTI — Airborne Moving Target Indicator
• MBS — Maximum Burst Size (ATM)
• CTI — Computer Telephony Integration
• PUK — PIN (Personal Identification Number) Unlocking Key
• MTS — Message Transmission Subsystem
• ISP — International Signaling Point
• APS — American Protective Services
• ANT — ADSL Network Terminator
• RFI — Remote File Inquiry
• DPBX — Digital Private Branch Exchange
• TTL — ToS and Time-to-Live
• ALT — Automatic Link Transfer
• SCC — Signal Conversion Circuit
• RADINT — Radar Intelligence
• LDI — Long Distance Interconnect
• WDMW — Web Directory for Mobile and Wireless
• 3G — 3rd Generation Wireless Format
• ASE — Application Service Element
• TDWR — Terminal Doppler Weather Radar
• PSN — Public Switched Network
• SAM — Service Access Multiplexer
• BTO — Betts Telecom Oklahoma
• IESG — Internet Engineering Steering Group
• B8ZS — Binary Eight Zero Substitution
• SRA — Seamless Rate Adaptation
• CDA — Communications Decency Act of 1996
• ATCA — Advanced Telecom Computing Architecture
• SVI — Service Interception
• F — Frequency
• CPN — Customer Premise Network
• WNMS — Wireless Network Management System
• CSR — Customer Service Request
• LMDS — Local Multipoint Distribution Service
• NCP — Network Control Program
• IDCP — Internet Device Control Protocol

• CAR — committed access rate
• CDVT — Cell Delay Variation Tolerance
• TSC — Technical Standards Committee
• B2B — Business-to-Business
• PAM — Payload Assist Module
• MITI — Ministry of International Trade and Industry
• DMS — Defense Messaging System
• GFC — Generic Flow Control (ATM)
• PLCP — Physical Layer Convergence Protocol (ATM)
• TDRSS — Tracking and Data Relay Satellite System
• RYP — Russian Yellow Pages
• IRF — Impulse Response Function
• RS-422 — Recommended Standard 422 (ANSI/EIA standard for transmitting serial data)
• DFE — Design For Environment
• EMS — Enhanced Messaging Service
• ECC — Emergency Communications Center
• TSDU — Transport Service Data Unit
• VOB — Voice Over Broadband
• IV&V — independent verification and validation
• NWK — Network
• MED — Manipulative Electronic Deception
• SAPI — Service Access Point Identifier
• SHR — Self-Healing Ring
• TELNET — Telecommunications Network Protocol
• L2TP — Layer 2 Tunneling Protocol
• SR — Slow Release
• DBN — Dial-Back Number
• SMG — Super Master Group
• ROW — Rest Of World
• DUV — Data-Under-Voice
• DNI — Data Network Interface
• STM — Synchronous Transfer Mode
• IOS — Internet Over Satellite
• 3G HSPA — Third-Generation High-Speed Packet Access
• INAP — Intelligent Network Application Part
• NEMP — Nuclear Electromagnetic Pulse
• QOI — Quality of Information
• LMT — Lightwave Microcell Transceiver
• ALCAP — Access Link Control Application Protocol
• MOS — Metal Oxide Semiconductor (FET Devices)
• RADSL — Rate Adaptive Digital Subscriber Line
• IPVX — Internet Protocol version X
• DACS — Digital Access and Cross-Connect System
• LPD — Low Probability of Detection
• SAR — Segmentation and Reassembly (ATM)
• VRT — Voltage Reduction Technology
• M/W — MicroWave
• EPP — Enhanced Parallel Port (PC)
• PLCP — Physical Layer Convergence Procedure
• MP — Master Processor

• UMTS — Universal Mobile Telecommunications Standard
• 4 GIG — 4 Giga Intellectual Gadget
• DCA — Distributed Communications Architecture
• PRM — Performance Report Message
• TTY — teletype terminal
• KSPS — KiloSymbols Per Second
• SCCS — Switching Control Center System
• CAMEL — Customized Applications for Mobile-network Enhanced Logic
• WFG — Wireless Firewall Gateway
• SMS — System Management Server
• BSVCI — Broadcast Signaling Virtual Channel Identifier
• TM — Thematic Mapper (Landsat)
• CPE — Customer Premise Equipment
• 4WA — Four Wire Analog
• B-CPE — Broadband Customer Premises Equipment
• BDFB — Battery Distribution Feeder Bay
• WSP — Wireless Service Provider
• OMA — Open Mobile Alliance
• COBE — Corporate Owned Business Only
• SS1 — Signalling System 1 (500/20 Hz tones)
• DXI — Data Exchange Interface
• LOP-P — Loss Of Pointer - Path
• ADPCM — Adaptive Differential Pulse Code Modulation
• C² — Command and Control
• DSSSL — Document Style Semantics and Specification Language
• ADTS — Ameritech Digital Transport Service
• IDCU — Integrated Digital Carrier Unit
• UNI — User-Network Interface
• ADTS — Automated Digital Terminal System
• PMOS — P-channel Metal Oxide Semiconductor
• ADP — Automatic Data Processor
• AS — Active Service
• CALA — Customer Address Location Area
• CSU — Channel Service Unit
• MTD — Moving Target Detection
• DPNSS — Digital Private Network Signaling System
• SDSL — Symmetric Digital Subscriber Line
• ATS — Air Traffic Services
• V — Vector
• MEH — Mobile-Executed Handoff
• WIG — Wireless Internet Gateway
• MTI — Moving Target Indicator
• DACS — Digital Access Cross-connect System
• CCLC — Carrier Common Line Charge
• CSAA — Central Service Area Authority
• MBE — Molecular Beam Epitaxy
• HTML — Hyper-Text Markup Language
• TFL — Telecom Fiji Limited
• CSDU — Core Service Data Unit
• URN — Uniform Resource Namespace

• OCI — object code insertion
• LAAS — Local Area Augmentation System
• CMM — Calls, Minimums, Maximums
• LFACS — Loop Facility Assignment and Control System
• DBRNC — deciBel Relative to Noise in a Circuit
• MDN — Mobile Directory Number
• WSA — Wireless Security Auditor
• OIM — Operations Interface Module
• ANSI — Advanced Network Signaling Input
• NCC — Network Control Center (GSFC)
• AEA — American Electronics Association's
• ESPN — Entertainment and Sports Programming Network
• ARPT — Autorité de Régulation des Postes et Télécommunications
• EADAS — Engineering and Administrative Data Acquisition System
• DAC — Digital to Analog Converter-Audio
• DOITT — Department of Information Technology and Telecommunications
• FRAD — Frame Relay Access Device
• MLA — Modern Language Association
• SR — Service Request
• MMDS — Multichannel Multipoint Distribution Service
• SINAD — SIgnal-to-(Noise And Distortion) ratio
• WCDMA — Wideband Code Division Multiple Access
• SETI — Search for Extraterrestrial Intelligence
• TSI — time-slot interchange
• BNCC — Base Network Control Center
• BUFR — Binary Universal Form for the Representation (of data)
• DMI — Desktop Management Interface (computing)
• MSI — Maritime Safety Information
• CLOS — Clear Line Of Sight
• DORK — Disciples Of The Righteous King
• SDHLR — Super-Distributed Home Location Register
• PNP — Positive-Negative-Positive
• VSM — Vestigial Sideband Modulation
• DW — Deep Water
• PNE — Path Number Efficiency
• IPXCP — Internetwork Packet Exchange Control Protocol
• TRANS — Transaction
• AGCH — Access Grant Channel
• DM — Design Manager
• SVC — Single Voice Coil
• CEE — Communaut? Economique Europ?enne
• CFOT — Certified Fiber-Optic Technician
• FSAI — Fiber Serving Area Interface
• ADM — Administration, Office of
• DTL — Defense Telephone Link
• TACACS — Terminal Access Controller Access Control System
• BT — Back Trace
• ITT — Invitation To Tender
• ALI — Automatic Location Identifier
• PCS — Personal Communications Services

• IPTD — Internet Protocol Telephony Design
• CLP — Cell Loss Priority (ATM)
• SFX — Special Effects
• SA — Selective Availability (on GPS transmissions)
• WAW — Wide Area Wireless
• CDR — Common Data Rate
• DMT — Discrete Multi-tone Transmission
• ARAI — Adjunct Route Application Interface
• EMV — EuroPay, MasterCard, Visa
• APTC — Atlantic Provinces Telecommunications Council
• GBPS — Gigabits per second
• AL — Alignment
• FD — Full Duplex
• RSI — Record Status Indicator
• RCR — Research and Development Center for Radio Systems
• TDM — Time Division Multiplexing
• FLL — Fixed-Loss Loop
• DLU — Digital Line Unit
• ARD — Automatic Ring Down
• CW — Call Waiting Supplementary Service
• MILNET — Military Network
• EA — expedited acknowledgement
• SACS — Security Access Control System
• IDLC — Integrated Digital Loop Carrier
• OID — Object Interaction Diagram
• CONS — Connection-oriented Network Services
• RNR — Receive Not Ready
• BB — Blackberry
• AECT — Association for Educational Communications and Technology's
• SDCCH — Standalone Dedicated Control Channel
• DS-3 — Digital Signal, Level 3
• DLT — Digital Line Termination
• CF — Coin First Payphone
• CR — Connection Request
• USPI — Universal Serial Phone Interface
• GOMP — Get Off My Phone
• AB — Answer Back
• WCMP — Wireless Control Message Protocol
• CMOS — Cellular Management Operation System
• SFN — Single Frequency Network
• ATU-C — ADSL (Asymmetric Digital Subscriber Line) Transceiver Unit - Central office end
• NESC — National Electrical Safety Code
• GSTN — General Switched Telephone Network
• VISSR — visible and infrared spin scan radiometer (GOES)
• 3GIP — Third Generation Internet Protocol
• DCSS — Digital Cross-connect Systems
• MCPC — Multiple Channels Per Carrier
• DX — Duplex Signaling
• NMC — Network Model Coverage
• ATL — Atlanta

• TBRL — Terminal Balance Return Loss
• AIU — Analog Interface Unit
• ARSR — Air Route Surveillance Radar
• EST — Electroshock Therapy
• HSC — High Speed Connect
• APR — Alarm Processing Remote
• UASL — Unified Access Service License
• PSK — Phase Shift Key
• BSRF — Basic System Reference Frequency
• PMMA — Polymethyl Methacrylate
• CM — Common Mode
• DMT — Discrete Multi-Tone Technology
• NLM — NetWare Loadable Module
• TC — Technical Committee (HL7)
• HDTV — High-Definition Television
• VTAC — Vermont Telecom Advancement Center
• DNU — Do Not Use
• LRF — Laser Range Finder
• CACM — Communications of the ACM
• RCMAC — Recent Change Memory Administration Center
• STDM — Statistical Time Division Multiplexing
• MOC — Maintenance and Operations Console
• BSSMAP — Base Station System Management Application Part
• CTSO — Cellular Telephone Service Order
• FEM — Finite Element Method
• WTP — Wireless Transaction Protocol
• ASYNC — Asynchronous
• CMAS — Cellular Management System
• MIN — Mobile Identification Number
• AMR — Automated meter reading also known as Automatic Meter Reading
• SYM — Symmetric
• SDNS — Secure Data Network System
• TOP — technical/office protocol
• MOA — Managed Object Agent
• LCAS — Link Capacity Adjustment Scheme
• ASA — Avaya Site Administration
• TD-CDMA — Time Division - Code Division Multiple Access
• FTAM — File Transfer Access and Management
• PSLV — Polar Satellite Launch Vehicle (Indian Space Research Organization; India)
• NSE — Network Software Environment
• DICOM — Digital Imaging and Communications in Medicine
• MAJ — Major
• AIS-V — Alarm Indication Signal - Virtual
• DLC — Digital Leased Circuit
• THL — Trans-Hybrid Loss
• VAS — Value Added Services
• MFLOPS — Millions of Floating Point Operations per Second
• BCM — Bit Compression Multiplexer
• FAT — Final Acceptance Testing
• JDC — Japan Digital Cellular

• RCH — Receive Channel
• VF0 — Voice Fundamental Frequency
• * — Star, special function key
• TOMS — Telecom Operations Management System
• OOK — On/Off Keying
• MOD — Modulo
• DMT — Discrete Multi-Tone
• PHY — Physical Layer
• RZ — Return to Zero
• TTC — Telemetry Telecommand and Control
• ECS — Environmental Control System (Subsystem)
• TDR — Time-Domain Reflectometry
• # — Number sign, octothorp; special function key
• IEEE-CS — Institute of Electrical and Electronics Engineers Computer Society
• GOS — Gerry Otis Simpson
• INWATS — INward Wide Area Telecommunications Service
• DLE — Digital Local Exchange
• 4G — Fourth Generation
• CERN — Conseil Europeen Pour La Recherche Nucleaire
• NSN — National Significant Number
• DDD — Direct Distance Dial
• BSC — Base Station Controller
• BCSM — Basic Call State Model
• DUV — Deep Ultraviolet
• WAWS — Washington Area Wideband System
• MQFP — Metric Quad Flat Pack
• MEAS — Measure
• E — Echo Time Zone
• CSAR — Combat Search and Rescue
• DF — Distributing Frame
• ZD — Zero Defects
• TPSP — Third Party Service Provider
• A/D — Analog-to-Digital converter
• SM — Statistical Multiplexing
• CAAS — Communications-as-a-Service
• DACS — Digital Access Carrier System
• SQE — Signal Quality Error
• LAPB — Link Access Protocol-Balanced
• BFS — Broadcast File System
• DEM — Digital Elevation Model
• ACA — Automatic Circuit Assurance
• AEE — Agent Execution Environment
• L2F — Layer 2 Forwarding protocol
• TMSI — Temporary Mobile Subscriber Identity
• RQMTS — Requirements
• JISC — Japanese Industrial Standards Committee
• RCF — Remote Call Forwarding
• AIS-L — Alarm Indication Signal - Line
• BDSL — Broadband Digital Subscriber Line
• LEED — Low-energy Electron Diffraction

• WCRL — Wireless Communications Research Laboratory
• LAT — Local Area Transport (network)
• MBMS — Multimedia Broadcast/Multicast Service
• NTU — Network Termination Unit
• SLF — Super Low Frequency
• DCS — Defense Communications System
• DIAG — Diagnostics
• DTW — Dynamic Time Warping
• BIC — Bus Interface Controller
• LQR — Line Quality Report
• IMPI — IP (Internet Protocol) Multimedia Private Identity
• COAM — Customer Owned And Maintained
• CSA — Canadian Standards Association (like UL)
• RSL — Request and Status Links
• Z — Zulu Time
• WPBX — Wireless Private Branch Exchange
• CDDI — Copper Distributed Data Interface
• SEM — Scanning Electron Microscopes
• LORAN — Long Range Aid to Navigation System
• MMC — Microsoft Management Console (Microsoft)
• CLEC — Competitive Local Exchange Carrier
• DVCC — Digital Verification Color Code
• TVRO — Television Receive-Only
• DEO — Digital End Office
• E2E — End-to-End
• PCIA — Personal Communications Industry Association
• MODEM — modulation and demodulation
• DQR — Directory enQuiry Restricted
• BANC — Broadband Access Network Coordination
• RBT — Ring Back Tone
• IXC — interexchange carrier
• LIU — Line Interface Unit
• RLC — Radio Link Control
• BTS — Base Transceiver Station (cellular)
• JWG — Joint Working Groupof
• FAW — Frame Alignment Word
• CDV — Cell Delay Variation(ATM)
• USRT — Universal Synchronous Receiver/Transmitter
• BAF — Bellcore AMA (Automatic Message Accounting) Format
• IEEE-SA — Institute of Electrical and Electronics Engineers - Standards Association
• GPBX — Global Private Branch eXchange
• CTIT — College of Telecommunications and Information Technology
• CSL — component sublayer
• MTS — message transport system
• WUP — Wired Up Privacy
• SLIC — Subscriber Loop Interface Circuit
• HFC — Hybrid Fiber Coaxial
• TIA — Telecommunications Industry Association
• ICLD — Inter-Channel Level Difference
• AH — Authentication Header

• FOTS — Fiber Optical Transmission System
• CARS — Community Antenna Relay Service
• MTP — Message Transfer Part
• ODS — Operational Data Store (knowledge management)
• CAM — Computer-Aided Manufacturing
• DCB — Digital Channel Bank (Sprint)
• ADTM — Asynchronous Data Transfer Mode
• VGC — Voice Grade Channel
• VC — Virtual Circuit (ATM)
• REG — range extender with gain
• MVDS — Microwave Video Distribution System
• STD — Standard Deviation
• ANSI-41 — ANSI standard for mobile management
• CP — Cell Phone
• DIP — Dialup Internet Protocol
• VCT — Variable Cam Timing
• ULP — Upper Layer Protocol
• BTN — Billing Telephone Number
• 1-ESS — x-ESS series of Electronic Switching Systems
• RPCU — Radio Port Control Unit
• ACNA — Access Customer Name Abbreviation
• DSP — Data Service Provider
• NICT — National Institute of Information and Communications Technology
• PTAM — Professional Telephone Answering Machine
• VHM — Voice Health Monitor
• BAN — Billing Account Number
• GTM — Go to Meeting
• NAM — Numeric Assignment Module
• UDC — Universal Digital Channel
• CCSA — Common Control Switching Arrangement
• 3GPP — Third-Generation Partnership Project
• DE — Discard Eligible
• CUSA — Central Urban Service Area
• BCST — Broadcast
• OODBMS — Object-Oriented Database Management Systems
• PSO — Professional Services Organization
• UBT — Universal Backend Tester
• ASP — Active Signaling Protocol
• MM — Multimode (fiber optic cable)
• TTIL — Team Telecom International Ltd.
• DFRI — Datacom Reference Frame Input
• NMC — Nortel Matra Cellular
• RDSS — Radio Determination Satellite Service
• 3-D — 3-Dimensional
• DSU — Digital Service Unit
• MIS — Miscellaneous
• IS — Integrated Services
• CNID — Calling Number Identification Display
• SMMR — Scanning Multichannel Microwave Radiometer
• SCORM — Shareable Content Object Reference Model

• CBS — Common Battery Signaling
• RADARSAT — Radar Satellite
• VVP — Versatile Voice Processing
• BAC — Bar Calls
• SNI — Service Node Interface
• CLI — Calling Line Identification
• SLC — Service Level Contract
• STD — Secondary Telecom District
• WBMP — Wireless Bitmap
• VPC — Virtual Path Connection (ATM)
• ACL — Asynchronous Connection-less Link
• VOFR — Voice Over Frame Relay
• GRX — GPRS Roaming Exchange
• RSN — Regional Service Network
• F/W — Firmware
• WPKI — Wireless Public Key Infrastructure
• CCSS6 — Common Channel Signaling System # 6
• DPT — Dial Pulse Terminate
• BHA — Busy Hour Attempts
• ULC — Universal Line Card
• DTS — Digital Terminal Systems
• REN — Ringer Equivalence Number
• ACOU — Additional Call Offering Unrestricted
• TRAC — Totally Reconfigurable Analog Circuit
• AEIMP — Apple Event Interprocess Messaging Protocol
• WDF — Wireless Data Forum
• VXML — Voice eXtensible Markup Language
• PFE — Power Feed Equipment
• MPLS — Multi Protocol Label Switching
• NECA — National Exchange Carrier Association
• MDCP — Media Device Control Protocol
• ATR — Advanced Telecommunications Research Institute
• NTSC — National Television Standards Committee
• TRLR — Trailer
• LAC — Line Assignment Center
• SSU — Synchronization Supply Unit
• TLP — Transmission Level Point
• BCIX — Berlin Commercial Internet Exchange
• ILETS — Idaho Law Enforcement Telecommunication System
• FSK — Frequency Shift Keying
• RAI — remote alarm indication
• E — Exchange
• TSM — Transaction State Machine
• BRAN — Broadband Radio Access Network
• CTTC — Centre Tecnològic de Telecomunicacions de Catalunya
• DRTT — Dial Repeating Tie Trunk
• GSM — Global System for Mobile telecommunications
• CEPT — Conference of European Posts and Telecommunications
• FIC — Flight Information Center
• AVT — Audio Visual Telecommunications

• DCMES — Dublin Core Metadata Element Set
• OST — Office of Science and Technology
• MMC — Minimum Monthly Charge
• SGCP — Simple Gateway Control Protocol
• AAL2 — ATM (Asynchronous Transmission Mode) Adaptation Layer 2
• CPC — Crosstalk Prevention Coding
• DORA — EV-DO (EVolution-Data Optimized) standard Revision A
• DOR — Detailed Outage Report
• JWP — Joint Working Party
• VDV — Voice/Data/Video
• PTM — Packet Transport Mode
• SASL — Simple Authentication and Security Layer
• USI — User System Interface
• BTL — Bell Telephone Laboratories, Inc.
• CIS — Communications and Information Systems
• CCS — Common Command Set
• SAP — Service Advertising Protocol
• ABATS — Automatic Bit Access Test System
• ECDIS — Electronic Chart Display Information System
• NARC — Non-Automatic Relay Center
• LSP — Label Switched Path
• SVW — Sioux Valley Wireless
• ADC — Advanced Data Control
• DPCM — Differential Pulse Code Modulator
• ASTE — Advanced Systems and Telecommunications Equipment
• HTO — Hellenic Telecommunications Organisation
• TAE — Terminal Adapter Equipment
• ISO — Independent System Operator (US) (see also TSO) Responsible for grid management, but does not own assets. (electricity)
• QR — Quality record
• EIR — Excess Information Rate
• MTA — Message Transfer Agents (Internet)
• VAD — Voice Activity Detection
• DMT — Digital-Discrete Multi-Tone
• TSAU — Time Slot Access Unit
• ASAS — All-Source Analysis System
• PN — Public Network
• MAPDU — Management Application Protocol Data Unit
• PNA — Parallel Network Architecture
• STE — Syrian Telecommunications Establishment
• DTC — Department of Telecommunications and Cable
• HFT — Human Factors in Telecommunications
• LTU — Line Terminating Unit
• ADM 3X — DS3 Add-Drop Multiplex
• HSCSD — High-Speed Circuit-Switched Data
• ATL — Advanced Technology Laboratory
• RA — Return Alarm
• PT — Payload Type (ATM)
• PWM — Pulse width modulation
• DAS — Data Acquisition System
• T&R — Tip and Ring

• DPDCH — Dedicated Physical Data Channel
• WLNP — Wireless Local Number Portability
• E-TDMA — Expanded Time Division Multiple Access
• JMA — Japanese Meteorological Agency
• DLIS — Directory Listing Inquiry System
• CATI — Computer-Assisted Telephone Interviewing
• NPSI — Network Packet Switching Interface
• SYSADM — System Administrator
• FPLMTS — Future Public Land Mobile Telecommunications System
• ESG — Enhanced Service Gateway
• RANAP — Radio Access Network Application Part
• LL — Lower Layer
• BMAS — Business Management System
• ACMA — Atlantic Cable Maintenance Agreement
• EGPRS — Enhanced General Packet Radio Service
• RDTD — Restricted Differential Time Delay
• LFTYR — Ley Federal de Telecomunicaciones y Radiodifusión
• WDSL — Wireless Digital Subscriber Line
• DMI — Digital Multiplex Interface
• CAE — Common Application Environment
• ISM — Interstellar Medium
• KEK — Key Encrypting Key
• LCGN — Logical Channel Group Number
• DF — Direction Finding or Finder
• ACE — Authentication Encryption
• ICTA — Idaho Cable Telecommunications Association
• TR — Temporal Reference
• PSC — Picture Start Code
• DAS — Distributed Antenna System
• IQ — In-phase and Quadrature
• CAL — Customer Access Line
• WDS — Wireless Distribution System
• DDS — Dataphone Digital Service (AT&T)
• ECAN — Echo Cancellation
• GERAN — GSM (Global System for Mobile communications) Edge Radio Access Network
• SCO — Synchronous Connection Oriented
• NETBIOS — Network Basic Input-Output System
• DI — Document Index
• NSDI — National Spatial Data Infrastructure
• DCS — Digital Cross-connect Switch
• PTO — U.S. Patent And Trademark Office
• AMC — Adds, Moves and Changes
• MT — maintenance
• ARQ — Admission Request
• UPC — Usage Parameter Control
• WTIA — Wireless Technology Industry Association
• ACRE — Authorization and Call Routing Equipment
• CVSD — Continuous Variable Slope Detection
• IVI — Intel Video Interactive
• RPV — Resource Property Value

• UMTS — Universal Mobile Telecommunication System
• RLS — Recursive Least Squares
• LSMS — Local Service Management System
• MHD — Maximum Hour Demand
• 2G — Second-generation mobile telephone system
• CSCC — coordinated state change control
• WSN — Wireless Sensor Network
• MHL — Mobile High-definition Link
• PTT — Post Telegraph and Telecommunications
• CCCI — Command, Control, Communications and Intelligence
• IDC — Information Distribution Company
• CPS — Cycles Per Second (now Hertz)
• ECTF — Enterprise Computer Telephony Forum
• DMF — Distributed Messaging Fabric
• EDT — European Deaf Telephone
• SVC — Signaling Virtual Channel
• TL — Telephone Lead
• COI — Community of Interest
• WITS — Web Interface for Telescience
• UPS — Un-interruptable Power Supply
• WWAN — wireless wide-area network
• EC — Echo Cancelling
• CNE — Certified Novell Engineer
• PPCH — Packet Paging Channel
• FLN — Fixed Line Network
• BTU — Basic Transmission Unit
• ITAD — Integrated Telephone Answering Device
• LUNT — Line Unit Network Termination
• WIPI — Wireless Internet Platform for Interoperability
• SUBT — Subscriber Terminal
• CD — Committee Draft
• ETB — Empresa de Telecomunicaciones de Bogotá
• STE — Software Test Environment
• BAOC — Barring of All Outgoing Calls supplementary service
• HUMAN — High-speed Unlicensed Metropolitan Area Network
• CT — Control terminal
• DSP — Domain Specific Part
• TCL — Transverse Conversion Loss
• ITOC — Independent Telephone Operating Company
• PET — positron emission tomography
• QLC — Quality Com
• CL — cell loss
• AUSPI — Association of Unified Telecom Service Providers of India
• RS — Receive Signature
• KTS — Key Telephone System
• IRAC — Interdepartment Radio Advisory Committee
• FWS — Fixed Wireless Services
• DQDB — Distributed Queue Double Bus
• RBOC — Regional Bell Operating Company (Baby Bell)
• TMF — Telecommunications Management Forum

• BUS — Broadcast and Unknown Server
• AAL — ATM (Asynchronous Transmission Mode) Adaptive Layer
• D3 — Digital channel bank, Third generation
• FOC — Fiber-Optic Cable
• VGF — Voice Grade Facility
• RDF — Remote Distribution Frame
• MSC — Mobile Switching Center
• CFS — Call for Service
• ILETS — International Law Enforcement Telecommunications Seminar
• AGPS — Assisted Global Positioning System
• APTG — Asia Pacific Telecom Group
• MVDM — Multiple Virtual DOS Machine
• AADS — Ameritech Advanced Data Services
• NSP — National Signaling Point
• CDPD — Cellular Digital Packet Data
• AFI — Authority and Format Identifier
• CODASYL — COnference on DAta SYstems Languages
• MIC — Management Integration Consortium
• ONE — Other Network Entity
• TWX — Teletypewriter Exchange (Telex)
• CMP — Connection Management Procedures
• UBL — Universal Bluetooth Link
• BBCR — BroadBand Communications Research
• BORSCHT — Battery feed, Overvoltage protection, Ringing, Signaling, Coding, Hybrid, and Testing
• SMAS — Service Management System
• PLM — Product Line Manager
• AFCEA — Armed Forces Communications and Electronics Association's
• UOS — Units of Service
• AQP — Association for Quality and Participation
• RFA — Recurrent Fault Analysis
• ISMI — International mobile subscriber identity
• DTU — Data Terminal Unit
• FEBE — Far End Block Error (SONET)
• SMASE — Systems Management Application Service Element
• DMB — Disconnect and Make Busy
• UVG — Universal Voice Grade
• ASIC — Application Specific Instruction Code
• WPC — Wireless Personal Communications
• WIPS — Wireless Intelligent Personal Server
• CNAD — Calling Name Delivery
• SNIX — Single Noise Interference Xterminator
• TJB — Telephone Junction Box
• IPCU — iPhone Configuration Utility
• ATU-R — ADSL (Asymmetric Digital Subscriber Line) Transceiver Unit - Remote terminal end
• WLAP — Wireless LAN (Local Area Network) Access Point
• BHCA — Busy Hour Call Attempts
• 4WE&M — Four-Wire Ear and Mouth
• CUG — Closed Users Group
• PPV — Pay-Per-View
• WTA — Wireless Telephony Application

• TPC — The Phone Company
• UTL — United Telecom Limited
• STAN — Supply of Telstra Account Number
• BTP — Business Telecom Products, Inc.
• QPA — Quality Performance Analysis
• NMF — Network Management Forum
• NDIS — Network Driver Interface Specification (Microsoft Windows NT)
• BTE — Broadband Terminal Equipment
• MC — Management Center
• RWIN — Receive Window
• VDSL — VHBR (Very High Bit Rate) Digital Subscriber Line
• CASP — Communications Application Service Provider
• EDGE — Enhanced Data for GSM (Global System for Mobile communication) Evolution
• CHT — Active
• GTXC — Global Telephone Exchange Carrier
• SLIP — Serial Line Internet Protocol
• ADIF — Accounting Data Interchange Format
• CSA — Central Service Area
• ROF — Reformat on the Fly
• CTS — Call Tracking System
• BGP4 — Border Gateway Protocol 4
• WRED — Weighted Random Early Detection
• WBA — Wireless Broadband Access
• NQA — Niveau de Qualite Acceptable
• DDSD — Delay Dial Start Dial
• MUSIC — MUltiple SIgnal Classification
• RLA — Received Level Average
• CMI — Computer Managed Instituteuction
• LULT — Line Unit/Line Termination
• ANCD — Automatic Network Call Distrubution
• FGDC — Federal Geographic Data Committee's
• PR — Preference
• DTV — Digital Television
• TCM — Tandem Connection Maintenance
• ATMS — automatic transmission measuring system
• BEAR — Billed Entity Applicant Reimbursement
• IMTS — Improved Mobile Telephone Service
• ATSC — Advanced Television Systems Committee
• ALC — Automatic Line Controller
• NRI — Net Radio Interface
• WCM — Wireless Connection Manager
• RTNR — Real-Time Network Routing
• DRTL — Dial Repeating Tie Line
• PRE — Preliminary
• SMSL — Standard Multimedia Scripting Language
• STN — Station Casinos, Inc.
• EA — Emergency Action (JOC)
• UR — User Rate
• GVPN — Global Virtual Private Network
• LSF — Line Spread Function

• LBX — Low Bandwidth X
• HBH — Hop-By-Hop
• BASH — Bandwidth Sharing
• VGCP — Voice Grade Channel Processor
• SNI — Subscriber-Network Interface
• TAU — Test Access Unit
• ISSI — Inter-Switching System Interface
• IPC — Initial Paging Channel
• JSC — Joint Scientific Committee (ICSU, WCRP, and WMO)
• SS6 — Signalling System 6
• SINS — Ship’s Inertial Navigation System
• GOSIP — Government Open System Interconnection Profile
• CFS — Customer Facing Services
• S&F — Store & Forward
• DOV — Data-Over-Voice
• CDF — Communications Data Field
• MEID — Mobile Equipment Identifier
• CRACK — Challenge Response for Authenticated Crypto Keys