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Computing & IT >> Telecom Abbreviations

Look through 4999 acronyms and abbreviations related to Telecom:

• IPB — Invision Power Board
• XFMR — Transformer
• DDRS — Dynamic Data Rate Selection
• CBCU — Centralized Broadband Control Unit
• LAN — Local Area Network
• DCE — Data Circuit-terminating Equipment
• EBITDA — Earnings before Interest, Taxes, Depreciation and Amortization
• DWDM — Dense Wavelength Division Multiplexing
• ETA — Estimated Time of Arrival
• YTD — Year To Date
• DOE — Distributed Object Environment
• YMMV — Your Mileage May Vary
• ECG — Electrocardiogram
• XML — Extensible Markup Language
• GFSK — Gaussian Frequency Shift Keying
• BRDF — Bidirectional Reflectance Distribution Function
• C3I — Command, Control, Communications & Intelligence
• CSR — Customer Service Representative
• SYN — Synchronous
• CT — Computed Tomography
• APR — Annual Percentage Rate
• OIC — Oh I See
• ROM — Read-Only Memory
• RDF — Resource Description Framework
• CSMA/CA — Carrier Sense Multiple Access/Collision Avoidance
• IQ — Intelligence Quotient
• CSMA/CD — Carrier Sense Multiple Access with Collision Detection
• ISAR — Inverse Synthetic-Aperture Radar
• IAMAI — Internet and Mobile Association of India
• YGWYPF — You Get What You Pay For
• FTP — File Transfer Protocol
• ATOM — Any Transport over MPLS (Multi-Protocol Label Switching)
• LASER — Light Amplification By Stimulated Emission Of Radiation (cf. Maser)
• DND — Do Not Disturb
• CSMA/CD — Carrier sense multiple access / collision detection
• CONG — Congestion message
• CSMA — Carrier Sense Multiple Access
• ANSI — American National Standards Institute, Inc.
• URL — Universal Resource Locator
• ASAP — As Soon As Possible (pronounced AY-sap)
• UK — United Kingdom of Great Britain and Northern Ireland
• ATM — Automatic Teller Machine
• MAN — Metropolitan Area Network
• X-BAR — Crossbar telephone exchange
• BBS — Bulletin Board Service
• RAEX — Roaming Agreement EXchange
• 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.
• IT — Information Technology
• LED — Light-Emitting Diode
• BPM — Beats Per Minute

• S-BCCH — Short Message Service Broadcast Control Channel
• FDIC — Federal Deposit Insurance Corporation
• XA-FR — Exchange Access Frame Relay
• BTW — By The Way
• S X S — Step-by-Step
• CPU — Central Processing Unit
• UAX 14 — Unit Automatic eXchange type 14
• X-ON — Transmitter On
• X-OFF — Transmitter Off
• OEM — Original Equipment Manufacturer (usually in reference to car parts)
• ISO — In Search Of
• MLS — Microwave Landing System
• CCTV — Closed-circuit television
• CPE — Customer Premises Equipment
• IRC — Internet Relay Chat
• EPA — Environmental Protection Agency (US)
• PPM — parts per million
• ZDBOP — Ziff-Davis Benchmark Operation
• DAM — Diagnostic Acceptability Measure
• WACN ID — Wide Area Communications Network IDentifier
• THX — Thanks
• C-NBAP — Common Node B Application Part
• C4I — Command, Control, Communications, Computers, & Intelligence
• B-ICI — Broadband Inter-Carrier Interface
• A-KEY — Authentication key
• OC-256 — Optical Carrier Signal, Level 256
• FIFO — First In, First Out
• SABGW — System Architecture Evolution Gateway
• VIP — Very Important Person
• D-H — Diffie-Hellman
• COB — close of business (End of duty day)
• F2F — Face To Face (also Meeting In Person)
• M-CSI — Mobility management CAMEL (Customized Applications for Mobile network Enhanced Logic) Subscription Information
• RFQ — Request For Quotation
• TEMIP — Telecommunications Management Information Platform
• POC — Point Of Contact
• ADM — Add-Drop Multiplexer
• SD — Standard Deviation
• T-IC — T-interConnect
• E-LEAD — Ear Lead
• LLC — Limited Liability Company
• AUP — Acceptable Use Policy
• PDR — Preliminary Design Review
• OC-18 — Optical Carrier Signal, Level 18
• OC-9 — Optical Carrier Signal, Level 9
• VC-ATOD — Virtual Clearinghouse on Alcohol, Tobacco and Other Drugs
• IP — Internet Protocol
• I.LINK — IEEE 1394, High Performance Serial Bus, implementation
• H323 — ANSI standard for format over IP
• QC — Quality Control

• T-CARRIER — Trunk Carrier
• RF — Radio Frequency
• FEMA — Federal Emergency Management Agency
• ISO — International Organization for Standardization
• D-NBAP — Dedicated Node B Application Part
• EDI — Electronic Data Interchange
• DAHDI — Digium/Asterisk Hardware Device Interface
• CDR — Critical Design Review
• EAP — Employee Assistance Program
• WTG — Way To Go
• DWDM — Dense Wavelength-Division Multiplexing
• KBYTE — Kilobyte (103)
• IRR — Internal Rate of Return
• GSM — Global System for Mobile Communications
• LCD — Liquid Crystal Display
• CY — Calendar Year
• DSC — Differential Scanning Calorimetry
• VAZO — Violating All-Zero Octet
• ACH — Automated Clearing House
• ISP — Internet Service Provider
• NMSE — Normalized Mean Square Error
• CCB — Change Control Board
• ASTM — American Society for Testing and Materials (Philadelphia, Pennsylvania)
• WWW — World Wide Web
• ECU — Electronic Control Unit
• RFP — Request For Proposal
• PO — Purchase Order
• CEO — Chief Executive Officer
• PDT — Pacific Daylight Time
• C³CM — Command, Control and Communications Countermeasures
• AC — Alternating Current
• FET — Field Effect Transistor
• AFAIK — As Far As I Know
• DBORS — Data Base of Records
• CV — Curriculum Vitae
• PDF — Portable Document Format (created by Adobe Acrobat)
• VAT — Value Added Tax
• CR — Carriage Return
• LRU — Line Replaceable Unit
• QFSK — Quadrature Frequency Shift Keying
• AMD — Advanced Micro Devices, Inc. (producer of computer chips)
• WBS — Work Breakdown Structure
• TQM — Total Quality Management
• ATM — Asynchronous Transfer Mode
• P&L — Profit and Loss statement
• CSA — Canadian Space Agency
• BTU — British Thermal Unit
• ADSL — Asymmetric Digital Subscriber Line
• IPO — Initial Public Offering
• ATTN — Attention

• DAC — Discretionary Access Control
• ABC — activity based costing
• WML — Wireless Markup Language
• API — Application Programming Interface
• R&D — Research & Development
• UDP — User Datagram Protocol (FDDI related)
• SAR — Search And Rescue
• ABI — Application Binary Interface
• MOU — Memorandum of Understanding (an MOU between Food & Drug Administratin and a regulatory agency in another country allows mutual recognition of inspections)
• RDY — Ready
• PDA — Personal Digital Assistant
• BVR — Beyond Visual Range
• EST — Eastern Standard Time
• SMTP — Simple Mail Transfer Protocol
• CU — See You
• CUG — Closed User Group
• RPI — Retail Price Index
• TNYWR — The Number You Will Receive
• AIR — Account Information and Refill
• IRL — In Real Life
• GIS — Geographic Information System
• DOA — dead on arrival
• BRB — Be right back
• ESA — European Space Agency
• EDS — Electronic Data Systems Corporation
• SRAM — Static Random Access Memory (ess-ram)
• ASCII — American National Standard Code for Information Interchange
• NYSE — New York Stock Exchange
• ASA — American Standards Association
• ASME — American Society of Mechanical Engineers
• EIS — Executive Information System
• GUI — Graphical User Interface (goo-ey)
• CD — Compact Disc
• MRI — Magnetic Resonance Imaging
• MTBF — Mean Time Before Failure
• GATT — General Agreement on Tariffs and Trade (government)
• SLA — Service Level Agreement
• ACE — Access Control Entry
• EOM — End Of Message
• DFD — Displaced Frame Difference
• COR — Carrier Operated Relay
• HTTP — Hypertext Transfer Protocol
• ACK — ACKnowledgment
• ATA — Area Transportation Authority
• JV — Joint Venture
• MBR — Master Boot Record
• DBMS — Database Management System
• GPS — Global Positioning System (ex-NAVSTAR)
• ICT — Information and Communication Technology
• SME — Subject Matter Expert

• WWW3 — World Wide Web Consortium
• ACC — Adaptive Cruise Control
• CCSDS — Consultative/Consultative Committee for Space Data Systems
• NFS — Network File System
• PSK — phase-shift keying
• SAN — Storage Area Network
• ATCRBS — Air Traffic Control Radar Beacon System
• EU — European Union (1994; formerly referred to as the EEC or EC)
• PCB — printed circuit board
• MOB — Mobile
• PUHU — Pick Up Hang Up
• CCM — counter-countermeasure
• CGI — Common Gateway Interface
• CIO — Chief Information Officer
• NPV — Net Present Value {economics}
• AM — Ante Meridian
• AIS — Automated Information System
• DSCP — Differentiated Services Control Point
• WB — Welcome Back
• FAA — Federal Aviation Administration
• NOS — Network Operating System
• RAM — random-access memory
• ARPA — Advanced Research Projects Agency (made early internet)
• RFC — Request For Comment
• FAQ — Frequently Asked Questions (sometimes Pronounced Fak)
• 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.
• CAE — Computer-Aided Engineering
• CPT — Carriage Paid To
• PVT — Private
• WEP — Wired Equivalent Privacy
• VM — Voice Mail
• AOL — America on line
• MST — Mountain Standard Time
• QMS — Quality Management System
• CPM — Critical Path Method
• MB — Megabyte
• PDH — Plesiochronous Digital Hierarchy
• SDR — Special Drawing Rights
• NPI — New Product Introduction
• COO — Chief Operation Officer
• GPRS — General Packet Radio Service
• BIP — Bit-Interleaved Parity
• CRT — Cathode Ray Tube (type of TV)
• WDM — Wavelength Division Multiplexing (fiber optics)
• LRJ — Location Reject
• EC — European Commission
• AES — Advanced Encryption Standard
• SDMA — Space Division Multiple Access
• PDN — Public Data Network
• AATSR — Advanced Along-Track Scanning Radiometer

• TTYL — Talk To You Later (Internet Slang)
• TBD — To Be Determined
• RDBMS — Relational Database Management System
• RPM — Revolutions Per Minute, (Rotations Per Minute)
• MIS — Management Information System (OSHA)
• FX — Foreign Exchange
• AM — Amplitude Modulation
• WAN — Wide Area Network
• IETF — Internet Engineering Task Force
• CIS — Commonwealth of Independent States
• O&M — Operation and Maintenance
• VPN — Virtual Private Network (ATM)
• MMS — Multimedia Messaging Service
• BUR — Bandwidth Usage Redundancy
• AE — Account Executive
• CS — Computer Science
• CB — Call Back
• DES — Data Encryption Standard
• ALC — Automatic Level Control
• FM — frequency modulation
• DB — Decibel
• SLIP — Serial Line Interface Protocol
• SCC — Standards Council of Canada
• DOD — United States Department of Defense
• ADD — Addendum
• APT — Automatic Picture Transmission
• ACK — Acknowledge (telecommunications; Cf. NAK)
• SWAG — Scientific Wild Ass Guess
• QOS — Quality of Service
• WWW — World Weather Watch
• IVR — Interactive Voice Response (telephone technology)
• UR — Your
• NIC — Network Interface Card
• DDD — Direct Distance Dial
• FIPS — Federal Information Processing Standard
• CIR — Committed Information Rate (Frame Relay)
• PGP — Pretty Good Privacy (encryption)
• BSD — Berkeley Software Distribution
• NATO — North Atlantic Treaty Organisation
• SQA — Software Quality Assurance
• RWR — Radar Warning Receiver
• ACM — Association for Computing Machinery
• AOA — Angle Of Arrival
• JIT — Just in time
• Y2K — Year 2000
• ADR — Address
• FAR — Federal Aviation Regulation
• RFI — Request For Information. Sales department shorthand. Special priority when use in conjunction with RFN (see below).
• STS — Space Transportation System
• AAC — Advanced Audio Coding

• UPS — Ultraviolet Photoelectron Spectroscopy
• RTN — Regional Telecommunication Network
• QA — Center for Quality Assurance in International Education
• DSS — Decision Support System
• ACL — Access Control List
• CBT — Computer Based Training
• UAV — Unmanned Aerial Vehicle
• DHCP — Dynamic Host Configuration Protocol
• MSN — Microsoft Network
• SCSI — Small Computer System Interface
• DSA — Digital Signature Algorithm
• MTTR — Mean Time To Repair
• DRAM — Dynamic Random Access Memory (dee-ram) (computing)
• CAD — Computer Aided Designer
• ACD — Automatic Call Distributor
• EEC — European Economic Community (predecessor of the European Union|EU)
• EVP — Executive Vice President
• VVX — Voice and Video eXchange
• PNG — Portable Network Graphics (graphic file standard/extension)
• CRM — Customer Relationship Management
• VHF — Very High Frequency
• POP — Point Of Presence (Internet)
• ACO — Additional Call Offering
• NIH — Not Invented Here
• SAS — Statistical Analysis System
• DNS — Domain Name System
• AGC — Automatic Gain Control
• SOW — Statement Of Work
• ACE — Advanced Computing Environment
• RM — Regional Manager
• DDL — Data Definition Language
• ROI — Return on Investment
• DARPA — Defense Advanced Research Projects Agency (US)
• RNC — Radio Network Controller
• DMSP — Defense Meteorological Satellite Program (U.S.)
• BCC — Blind Carbon Copy
• AES — Auger Electron Spectroscopy
• CDR — Call-Detail Record
• 100BASE-T2 — 100 Megabits per Second, Baseband, Two-pair Category 3 UTP cables
• CAUCE — Coalition Against Unsolicited Commercial Email
• ABET — Accreditation Board for Engineering and Technology, Inc.
• OCR — Optical Character Recognition
• GSA — U.S. General Services Administration
• ISDN — Integrated Services Digital Network
• EFF — Electronic Frontier Foundation
• AME — Amplitude Modulation Equivalent
• AD — Active Directory
• ATC — Air traffic control
• ADM — Add/Drop Multiplexer
• DME — Distance Measuring Equipment

• EBCDIC — Extended Binary Coded Decimal Interchange Code (pronounced Eb-see-dik) (cf. BCD)
• ENIAC — Electronic Numerical Integrator And Computer
• TCO — Total Cost of Ownership
• EW — Electronic Warfare
• DOJ — Department of Justice (US)
• ABR — Available Bit Rate
• PM — Preventive Maintenance
• OBO — Or Best Offer
• DTE — Data Terminal Equipment
• CC — Carbon Copy
• DC — Direct Current
• RM — Resource Management
• AC — Access Control
• CFO — Communication Filing Officer
• ECO — Engineering Change Order
• HSD — High Speed Data
• JAXA — Japan Aerospace Exploration Agency
• RAID — Redundant Array of Inexpensive Disks
• CMI — Computer Managed Instruction
• RQMT — Requirement
• SIC — Standard Industrial Classification (Code)
• TCP — Transmission Control Protocol
• DFS — Distributed File System
• IRS — U.S. Internal Revenue Service
• SDD — Software Design Document
• CU — Control Unit
• TNSTAAFL — There's No Such Thing As A Free Lunch
• FFT — Fast Fourier Transform
• PERT — Program Evaluation and Review Technique
• RACON — Radar Beacon
• PRI — Primary Rate Interface (ISDN)
• TCB — Trusted Computing Base
• OMG — Object Management Group
• BR — Branch
• SBU — Strategic Business Units
• CAM — computer aided manufacturing
• PC — Personal computer (host)
• ISAKMP — Internet Security Association and Key Management Protocol
• Q&A — Question & Answer
• SEI — Software Engineering Institute
• NEC — National Electrical Code
• VR — Virtual Reality
• ASR — Airport Surveillance Radar
• HVAC — Heating, Ventilation, and Air Conditioning
• ASK — amplitude shift keying
• RPC — Remote Procedure Call
• EMG — Electromyogram
• VTC — Video Teleconference
• ERP — Enterprise Resource Planning
• DSL — Digital Subscriber Line

• AVHRR — Advanced Very High Resolution Radiometer  
• IM — Instant Message
• VIRUS — Vital Information Resources Under Siege
• LEO — Low Earth Orbit (satellite communications)
• SMS — Short Message Service
• CDT — Central Daylight Time
• DTX — Discontinuous Transmission
• ZIP — Zone Improvement Plan
• RU — Are You?
• ATM — Adobe Type Manager
• CMM — Capability Maturity Model
• AAAI — American Association for Artificial Intelligence's
• TNX — Thanks
• AQL — Acceptable Quality Level
• NIST — National Institute of Standards and Technology
• ASP — Application Service Provider
• BBS — Bulletin Board System
• DLR — Design Layout Record
• BST — British Summer Time
• SLF — Super Low Frequency
• UHF — Ultra High Frequency (300-3000 MHz; 1m-10cm)
• QI — Quality Improvement
• CTD — Cumulative Trauma Disorder
• USB — Universal Serial Bus
• CHAP — Challenge Handshake Authentication Protocol (ATM)
• DDE — Dynamic Data Exchange (in software parlance)
• ATN — Aeronautical Telecommunication Network
• MRC — Monthly Recurring Charge
• CCIS — Common Channel Interoffice Signaling
• ADPE — Automatic Data Processing Equipment
• ISRO — Indian Space Research Organisation
• AGP — Accelerated Graphics Port
• I/O — Input/Output
• DQE — Detective Quantum Efficiency
• UI — User Interface
• SQL — Structured Query Language
• MLS — Multiple Listing Service
• EFT — Electronic Funds Transfer
• BECN — Backward Explicit Congestion Notification
• CFE — Contractor-Furnished Equipment
• ITU — International Telecommunication Union
• DLL — Dynamic Link Library (computer file)
• AF — Audio Frequency
• CMS — Content Management System
• TC — Telephone Call
• NSF — National Sanitation Foundation
• CRL — Certificate Revocation List
• CM — Configuration Management
• EAP — Extensible Authentication Protocol
• EEG — Electro-EncephaloGram

• SOHO — Small Office Home Office
• B3ZS — bipolar 3-zero substitution
• DNS — Domain Name Service
• MDA — Monochrome Display Adapter
• CLI — Command line Interface (Cabletron)
• ATS — applications technology satellite
• EDT — Eastern Daylight Time
• ATF — Advanced Tactical Fighter
• DSTE — Digital Subscriber Terminal Equipment
• CAA — Civil Aviation Authority
• PAR — Precision Approach Radar
• AE — Application Entity
• APIC — Advanced Programmable Interrupt Controller
• BPR — Business Process Re-engineering
• SP — Service Provider
• 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
• PECVD — Plasma-Enhanced Chemical Vapor Deposition
• DQPSK — Differential Quadrature Phase-Shift Keying
• SAIC — Science Applications International Corporation
• CRC — Contrôle de Redondance Cyclique (French: Cyclic Redundancy Check)
• USD — United States Dollar
• RFO — Reason For Outage
• NMR — Nuclear Magnetic Resonance
• SGML — Standard Generalized Markup Language
• OSI — Open Systems Interconnection (iso Standard)
• SXS — Step-By-Step
• UTC — Coordinated Universal Time
• UN — United Narions
• AAAS — American Association for the Advancement of Science
• OSHA — Occupational Safety and Health Act (1970)
• SIG — Special Interest Group
• PLD — Programmable Logic Device
• AP — Application Protocol
• AADC — Automated Area Distribution Center
• EPR — Ethylene-Propylene Rubber
• CST — Central Standard Time (UTC-6 Hours)
• FDDI — Fiber Distributed Data Interface
• ARP — Address Resolution Protocol (ATM)
• WIPO — World Intellectual Property Organization
• W3C — World Wide Web Consortium
• NMT — Nordic Mobile Telephone
• AFC — Automatic Frequency Control
• B2B — Business to Businesse
• DMTS — Distinguished Member Of Technical Staff
• ROS — Return on Sales
• SCM — Supply Chain Management
• LED — law enforcement desk; light emitting diode
• PMA — Physical Medium Attachment
• CBC — cipher block chaining
• NSA — National Security Agency

• ERP — Enterprise Resource Management
• PE — Polyethylene
• WYSIWYG — What You See Is What You Get (pronounced Wizzy-wig. See Entry For Derived Acronyms)
• GRE — Generic Routing Encapsulation
• M — Meter
• AT&T — American Telephone and Telegraph (U.S. company, also known as "Ma Bell")
• SBC — Southwestern Bell Corporation
• BCD — Binary-Coded Decimal
• 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
• COQ — Cost Of Quality
• HZ — cycles per second (hertz)
• MAC — Message Authentication Code
• FCA — Free Carrier
• TV — Television
• FCC — Federal Communications Commission (US)
• EDVAC — Electronic Discrete Variable Automatic Computer
• ERT — Emergency Response Team
• DOS — Disk Operating System
• WLTF — Wireless LAN (Local Area Network) Task Force
• IP — Intellectual Property
• MHS — Message Handling System (electronic)
• AEC — Architecture, Engineering, Construction
• NTIS — National Technical Information Service Technology Administration
• PT — Project Team
• HDML — Handheld Device Markup Language
• BER — Bit-Error Rate
• PM — Project Manager
• AT — Advanced Technology
• TAC — Technical Assistance Center
• LCP — Link Control Protocol
• NEMA — National Electric Manufacturer's Association
• BRI — Basic Rate Interface
• TOS — Type Of Service
• CIM — Common Information Model
• CW — Continuous Wave
• NA — Not Applicable
• ROFL — Rolling on the floor laughing
• SVP — Senior Vice President
• OSS — Operational Support System
• RFI — Radio Frequency Interference
• JIS — Japanese Industrial Standard
• Z — Zero
• ISS — International Space Station
• NTIA — National Telecommunications and Information Administration
• DIT — Directory Information Tree
• CIA — Central Intelligence Agency
• ICMP — Internet Control Message Protocol
• AMT — Amount
• WAFB — Wireless Absolute Fairness Bound
• EGA — Enhanced Graphics Adapter

• EOT — End Of Transmission
• DCN — Design Change Notification
• EEPROM — Electrically Erasable Programmable Read-Only Memory
• ADT — Abstract Data Type
• ISO — Infrared Space Observatory
• HSDPA — High-Speed Downlink Packet Access
• BT — British Telecommunications
• WMO — World Meteorological Organization (ICSU)
• FCS — Frame check sequence (Ethernet)
• BBU — Baseband Unit
• VAC — Vacant
• ADF — Automatic Direction Finder
• URI — Uniform Resource Identifier
• PWD — Password
• QAM — quadrature amplitude modulation
• LF — Low Frequency
• OS — Operating System
• SPC — Stored Program Control
• CIC — Circuit Identification Code
• NOAA — National Oceanic and Atmospheric Administration (US)
• MIC — Message Integrity Check
• DTI — Department of Trade and Industry (UK)
• DLC — Digital Loop Carrier
• AWG — American Wire Gauge
• PDU — Protocol data unit (such as segment, packet, frame, etc.)
• ACFQ — Absence Compensation Fair Queuing
• RCU — Remote Control Unit
• KISS — Keep It Simple Stupid
• ISSN — International Standard Serial Number (ISO 3297)
• MS — Mobile Station
• FCW — Federal Computer Week
• IANA — Internet Assigned Numbers Authority
• MOS — Model Output Statistics
• BS — Base Station
• PST — Pacific Standard Time (UTC-8 Hours)
• UAS — Unavailable Seconds
• PPB — parts per billion (109)
• MF — Medium Frequency
• LP — Low Pressure
• RIP — Routing Information Protocol
• DCE — Distributed Computing Environment
• TPDU — Transport Protocol Data Unit
• MS — Message Store
• ISBN — International Standard Book Number (ISO 2108)
• OFC — Office
• CORBA — Common Object Request Broker Architecture
• AMI — Advanced Metering Infrastructure
• PLMN — Public Land Mobile Network
• JPEG — Joint Photographic Experts Group (24-bit image storage format)
• DMX — De-MultipleXer

• OSPF — Open Shortest Path First (ATM)
• AXE 10 — Series of electronic telephone exchanges from L.M. Ericsson
• JPL — Jet Propulsion Laboratory (California Institute of Technology) (NASA)
• STP — standard temperature and pressure (0° and 1 atm)
• FTTB — Fiber To The Building
• MDF — Main Distribution Frame
• CUL — See You Later
• IMEI — International Mobile Equipment Identity
• CAM — Computer-Aided Mapping
• AS — Autonomous System
• CIM — Corporate Information Management
• BPRZ — Bipolar Return-to-Zero
• ASQC — American Society for Quality Control's
• DSA — Directory System Agent
• IMPACT — Integrated Manufacturing Precision Assembly Cellular Technology
• IRLAN — Infrared LAN
• RDP — Radar Data Processing
• DT — DWDM (Dense Wavelength Division Multiplexing) Terminal
• CDMA — Code Division Multiple Access (voice/data transmission)
• CERT — Computer Emergency Response Team
• SAE — Society of Automotive Engineers
• VDS — Variable Depth Sonar
• BIS — Bureau of Indian Standards
• EDP — Electronic Data Processing Plc (London Stock Exchange [LSE])
• FASB — Financial Accounting Standards Board
• DMA — direct memory access (computer term)
• ITSEC — Information Technology Security Evaluation Criteria
• ACTV — Active
• MS — Millisecond
• PSTN — Public Switched Telephone Network
• SNMP — Simple Network Management Protocol (ATM)
• KHZ — kilohertz (1000 cycles per second)
• T&C — Terms & Conditions
• JSC — Johnson Space Center (Houston, TX)
• DUP — Duplicate
• EISA — Extended Industry Standard Architecture
• HDLC — High-Level Data Link Control
• PM — post meridian
• SPC — Statistical Process Control. Forerunning quality theory from the 1960s to TQC and TQM.
• IW — Information Warfare
• RCC — Rescue Coordination Center
• PABX — private automatic branch exchange (telephone)
• NAS — Network Access Server
• ME — Mobile Equipment
• ARA — Apple Remote Access
• SIL — Speech Interference Level
• YP — Yellow Pages
• NESDIS — National Environmental Satellite, Data, and Information Service
• TCP/IP — transmission control protocol/internet protocol
• MMU — Memory Management Unit

• VB — Visual Basic
• LLC — Logical Link Control
• CATV — Cable Television
• LCN — Logical Channel Number
• HW — Hardware
• RACF — Resource Access Control Facility
• DNIS — Dialed Number Identification Service
• GB — Gigabyte
• WTO — World Trade Organisation
• TLS — Transport Layer Security
• SHA — Secure Hash Algorithm
• RAD — Rapid Application Development
• PBX — Private Branch eXchange (company phone system)
• SSL — Secure Socket Layer
• AT&T — American Telephone & Telegraph
• MIME — Multipurpose Internet Mail Extension
• DTR — Data Terminal Ready
• FC — Fibre Channel
• C4 — Command, Control, Communications, and Computers
• ADT — Atlantic Daylight Time (UTC-3 Hours)
• DSSS — Direct Sequence Spread Spectrum
• AT — Access Tandem
• RFS — Request For Service
• BSOD — Blue Screen Of Death
• IS — Intermediate System
• CDS — Cell Directory Service
• MVS — Multiple Virtual Storage
• RTU — Remote Terminal Unit
• DOM — Document Object Model
• PIN — Personal Identification Number
• LMS — Learning management system
• ECP — Engineering Change Proposals
• PPP — Point-to-Point Protocol
• NIST — National Institute of Standards & Technology (US)
• KM — Knowledge Management
• PDS — Protected Distribution System
• BPS — bits per second
• DSP — Digital Signal Processor
• IEC — International Electrotechnical Commission
• TM — Technical Manual
• NAFTA — North American Free Trade Agreement
• SSM — Source-Specific Multicast
• OM — Old Man
• EDD — Envelope Delay Distortion
• LEC — Local Exchange Carrier
• DCOM — Distributed Component Object Model
• CS — Cable Select
• ASEAN — Association of South East Asian Nations
• CFD — computational fluid dynamics
• RFD — Request For Discussion

• SEM — Space Environment Monitor
• ELF — Extremely Low Frequency
• VOL — Volume
• PAL — Programmable Array Logic
• HF — High Frequency
• BNSC — British National Space Centre
• OMS — Optical Multiplex Section
• CATV — Community Antenna Television
• MS — Management System
• ECN — Explicit Congestion Notification
• CCSD — command communications service designator; control communications service designator
• APC — American Power Conversion
• RSVD — Reserved
• DPC — Destination Point Code
• NCSA — National Center for Supercomputing Applications
• HTTPS — HyperText Transfer Protocol Secure
• NRC — National Research Council (Canada)
• MCSD — Microsoft Certified Solution Developer
• ECE — Economische Commissie voor Europa (United Nations) (Dutch: Economic Commission for Europe)
• 3G — Third Generation mobile phone network
• CLNP — ConnectionLess-mode Network Protocol
• AMI — Alternate Mark Inversion
• ICANN — Internet Corporation for Assigned Names and Numbers
• ELINT — Electronic Intelligence Satellite
• AVL — Available
• VM — Virtual Machine
• CG — Coast Guard
• SIT — Static Induction Transistor
• B2C — Business-to-Consumer
• TS — Technical Specification
• COO — Cost of Ownership
• STI — Speech Transmission Index
• PCI — Peripheral Component Interconnect
• SNR — Signal-to-Noise Ratio
• LF — Line Feed
• ISAS — Institute of Space and Astronautical Sciences (Japan)
• AML — Amplitude Modulated Link
• WAP — Wireless Application Protocol
• NBS — National Bureau of Standards (US)
• D-RAM — Dynamic Random Access Memory
• CC — Call Control
• IS — International Standard
• OTN — Optical Transport Network
• IPX — Internetwork Packet Exchange
• CGI — Computer-Generated Imagery
• ADC — Analog-Digital Converter
• AR — Access Rate
• CEV — Controlled Environment Vault
• ADN — Advanced Digital Network
• SCADA — Supervisory Control And Data Aquisition

• EMC — Electromagnetic Compatibility
• TB — Terabyte
• CES — Consumer Electronics Show
• PAN — Personal Area Network
• STM — Short Term Memory
• CBDS — Connectionless Broadband Data Service
• LPE — Liquid Phase Epitaxy
• SVC — Scalable Video Coding
• SML/SMS — Service Management Layer/Service Management Service
• APPL — Application
• MHS — Microwave Humidity Sounder
• WMAN — Wireless Metropolitan Area Network
• ASI — Asynchronous Serial Interface
• BYOD — Bring Your Own Device
• EMS — Express Mail Service
• CA — Certificate Authority
• NLMS — Normalized Least Mean Square
• PRF — Pulse Repetition Frequency
• RMS — root mean square (preferred over "RMS")
• ISI — Inter-Symbol Interference
• MAC — Media Access Control
• BRA — Basic Rate Access
• CO — Certificate of Origin
• VOD — Video On Demand
• COM — Component Object Model
• WS — Workstation
• DASD — Direct Access Storage Device
• ARPU — Average Revenue Per User
• MPI — Message Passing Interface
• DIBL — Drain-induced Barrier Lowering
• ECR — Electronic Cash Register
• ASQ — Alpha System Qualification
• MIPS — Millions of Instructions Per Second
• BUS — Business
• 1000BASE-T — 1000 Megabits per Second, Baseband, Twisted Pair
• RTS — Request To Send
• PVC — Permanent Virtual Circuit (ATM)
• LD — Long Distance
• EAI — Enterprise Application Integration
• USGS — United States Geological Survey (DOI)
• DCS — Digital Cross-connect System
• AIS — Alarm Indication Signal
• OAS — Organization of American States
• CABS — Carrier Access Billing System
• VLF — Very Low Frequency
• MIB — Management Information Base (ATM)
• FCA — Free Carrier Absorption
• IIS — Internet Information Services
• WB — Write Back
• ZIP — Zone Information Protocol

• FTTH — Fiber To The Home
• LSR — Local Service Request
• CFA — Carrier Facility Assignment
• IDT — Integrated Digital Terminal
• MDA — Model Driven Architecture
• ECMA — European Computer Manufacturer's Association
• CIS — CompuServe Information Service
• E — Energy
• CAB — Conformity Assessment Body
• COMJAM — Communications Jamming
• RAN — Radio Access Network
• RH — Relative Humidity
• DS — Digital Signal
• STA — State
• ISA — Industry Standard Architecture
• BJT — Bipolar Junction Transistor
• NIC — Network Information Center
• EPR — Electron Paramagnetic Resonance
• SPI — Service Provider Interface
• ACR — Attenuation Crosstalk Ratio
• PAP — Password Authentication Protocol (ATM)
• VOIP — Voice Over IP (Internet Protocol)
• CMP — Connection Management Protocol
• CSO — Customer Service Operations
• TE — Traffic Engineering
• BGP — Border Gateway Protocol (routing protocol)
• UAN — Universal Access Number
• CHF — Swiss Franc
• RCV — Receive
• NOTAM — Notice to Airmen
• F — Fellow
• AU — Audio Unit
• DA — Destination Address
• YL — Young Lady
• DIS — Distributed Interactive Simulation
• FR — Frame Relay
• WG — Working Group
• HSS — Home Subscriber Server
• DUC — Digital Up-Converter
• SA — Scientific American
• UA — User Agent
• DAP — Directory Access Protocol
• MC — Message Center
• RSVP — Resource Reservation Protocol (Internet)
• IRS — Interface Requirements Specification
• AFSK — Audio Frequency Shift Keying
• NTFS — New Technology File System
• DSN — Deep Space Network - network of large antennas and communication facilities.
• AFS — Andrew File System
• CIFS — Common Internet File System

• SCTP — Stream Control Transmission Protocol
• UPS — Uninterruptible Power Supply
• PD — Public Domain
• NI — Network Interface
• NIS — Network Information Service
• ATSR — Along-Track Scanning Radiometer
• CRO — Central Records Office
• CRIS — Carrier Route Information System
• IN — Intelligent Network
• SM — Senior Member
• CG — Center of Gravity (DXS)
• TBD — To Be Decided
• ESTEC — European Space Research and Technology Centre
• TEC — Total Electron Content
• FXO — Foreign Exchange Office
• NCS — National Communications System
• TAG — Technical Advisory Group for Biological Control Agents of Weeds
• STP — Spanning Tree Protocol
• OLE — Object Linking and Embedding (Microsoft communication protocol)
• TOP — Technical Office Protocol
• ECT — Explicit Call Transfer
• CAV — Constant Angular Velocity
• MSU — Microwave Sounding Unit
• CCTA — Central Computer and Telecommunications Agency
• MCU — Multipoint Control Unit
• WPAN — Wireless Personal Area Network
• VOP — Voice Over Packet
• ASR — Automatic Speech Recognition
• ES — Errored Second
• FAX — Facsimile
• NLM — National Library of Medicine (National Institutes of Health)
• FA — Functional Area
• LDAP — Lightweight Directory Access Protocol (pronounced Ell-dap)
• FCP — Fibre Channel Protocol
• BT — BlueTooth
• LLU — Local Loop Unbundling
• TG — Task Group
• SOGA — Share of Gross Adds
• MTSO — Mobile Telephone Switching Office
• MCD — Magnetic Circular Dichroism
• LPC — Linear Predictive Coding
• ANI — Automatic Number Identification (Caller ID)
• AEW — Airborne Early Warning
• ACT — ACTIVITY, ACTIVITIES
• RSN — Real Soon Now [which may be a long time coming]
• JST — Japan Standard Time
• CAN — Campus Area Network
• CTS — Clear To Send
• CF — Compact Flash
• AMHS — Automated Message Handling System

• CAC — Carrier Access Code
• VLL — Virtual Leased Line
• EMR — Electromagnetic Radiation
• PGA — Programmable Gate Array
• EPABX — Electronic Private Automatic Branch Exchange
• AYT — Are You There
• AMLCD — Active Matrix Liquid Crystal Display
• MPLS — Multi Protocol Label Switching
• MME — Mobility Management Entity
• MGMT — Management
• CMD — Command
• RSRQ — Reference Signal Received Quality
• ASIC — application-specific integration circuit
• EEA — European Economic Area
• ADCCP — Advanced Data Communications Control Procedures
• SAR — Specific Absorption Rate
• GDS — Global Distribution System
• IP — Intelligent Peripheral
• EAS — Extended Area Service
• STP — Signal Transfer Point
• LZ — Landing Zone
• NOC — Network Operations Center
• APS — Automatic Protection Switching (SONET/SDH)
• BPDU — Bridge Protocol Data Unit
• VCC — Virtual Channel Connection (ATM)
• ASR — Access Service Request
• BOC — Bell Operating Company
• P — Predicted
• ACPI — Advanced Configuration and Power Interface
• PDN — Packet Data Network
• BIOS — Basic Input Output System
• UL — Uplink
• DCP — Design Change Package
• SKU — Stockkeeping Unit
• CSPRM — Common Signaling Protocols Resource Module
• ESS — Electronic Switching System
• AFP — AppleTalk Filing Protocol
• SOAP — Simple Object Access Protocol
• BACP — Bandwidth Allocation Control Protocol
• CT — Computer Telephony
• GOS — Grade Of Service
• SW — South West
• FUP — Fair Use Policy
• MD — Mediation Device
• CBP — Coded Block Pattern
• SVD — Singular Value Decomposition
• M — Management
• MSR — Microwave Scanning Radiometer
• SDH — Synchronous Digital Hierarchy (ATM)
• RARP — Reverse Address Resolution Protocol

• JVM — Java Virtual Machine
• MSE — Mobile Subscriber Equipment
• PET — positron emission tomography
• TTYL — Type To You Later
• TN — Telephone Number
• YYP — Yahoo Yellow Pages
• DMARC — Demarcation point
• VOC — Volatile Organic Compounds (air pollution)
• BS — Beam Splitter
• STK — Satellite Tool Kit
• SEC — Software Engineering Center
• TCSEC — Trusted Computer System Evaluation Criteria
• CAD — Computer-Aided Design
• AOI — Area Of Interest
• MP — Multilink Protocol
• DC — Disconnected
• WPM — speech--words per minute
• DID — direct inward dial
• RDF — Radio Direction Finder
• RRN — Routing Recording Number
• PKI — Public Key Infrastructure (cryptography)
• APM — Advanced Power Management
• OSTP — Office of Science and Technology Policy
• OTS — Optical Transmission Section
• YAHOO — You Are Hazy Over Oranges
• SCP — Service Control Point
• SLP — Service Location Protocol
• DDS — Digital Data Service
• MBPS — Megabits per second
• OC — Optical Carrier
• TRM — Technical Reference Model
• EAC — Engineering Accreditation Commission
• TWT — Traveling Wave Tube
• MCA — Micro Channel Architecture
• PCMCIA — Personal Computer Memory Card International Association
• ARINC — Aeronautical Radio Incorporated
• DRM — Digital Rights Management
• IRDA — Infrared Data Association
• DVP — Digital Voice Privacy
• DOT — Department of Telecommunications (India)
• DBS — Direct Broadcast Satellite
• SPADATS — Space Detection And Tracking System
• FAT — File Allocation Table
• VXML — Voice eXtensible Markup Language
• SHF — Super High Frequency
• BLOS — Beyond Line-Of-Sight
• DX — Duplex
• PPARC — Particle Physics and Astronomy Research Council
• BG — Background
• ROSAT — Roentgen Satellite

• NMS — Network Management System
• OAM&P — Operations, Administration, Maintenance & Provisioning
• CGM — Computer Graphics Metafile
• ROTFL — Roll On The Floor Laughing
• ADEOS — ADvanced Earth Observing Satellite (Japan)
• ESF — Edge Spread Function
• EOB — End Of Business
• PDC — Personal Digital Cellular
• SBC — Session Border Controller
• BERT — Bit Error Rate Tester (telecommunication)
• ARPANET — ARPA Network
• OLAP — Online Analytical Processing
• OPC — Originating Point Code
• STN — Station Casinos, Inc.
• ARIN — American Registry for Internet Numbers
• VAS — Value Added Services
• EC — European Community
• FITS — Flexible Image Transport System
• RA — Risk Analysis
• CBEMA — Computer & Business Equipment Manufacturers Association
• RT — Remote Terminal
• PSD — Phase-Sensitive Detector
• TOS — Temporarily Out of Service
• CMC — Career Management Center
• WPS — Wireless Priority Service
• DCMI — Dublin Core Metadata Initiative (Online Computer Library Center)
• POTS — Plain Old Telephone Service (FCW)
• ECAC — European Civil Aviation Conference
• LEP — Large Electron Positron
• AAF — Advanced Authoring Format
• TO — Technical Order
• AIFF — Audio Interchange File Format
• Y — Yttrium
• CCD — Charge Coupled Device - a device for the movement of electrical charge.
• MTU — Maximum Transmission Unit
• CSAT — Customer Satisfaction
• UML — Unified Modeling Language (Object Management Group, OMG)
• ITT — Invitation To Tender
• AAS — Adaptive Antenna System
• VGA — Video Graphics Array
• CMT — Cadmium Mercury Telluride
• WWAN — Wireless Wide Area Network
• RCS — Radar Cross Section
• AFM — Atomic Force Microscopy
• ECPA — Electronic Communications Privacy Act 1986
• NNTP — Network News Transfer Protocol
• PUB — Publication (file name extension)
• CFD — Call For Discussion
• KB — Kilobyte: One thousand and twenty-four bytes kbps kilo bit per second
• NIMBY — Not In My Back Yard

• WLAN — Wireless Local Area Network
• SAN — System Area Network
• SVC — Switched Virtual Connection
• PCM — Pulse-Code Modulation
• BIP — Band Interleaved by Pixel
• ADP — Automatic Data Processor
• EX — Exercise
• CD — Critical Dimension
• SATAN — Security Administrator Tool for Analyzing Networks
• DEC — Decimal
• BOFH — Bastard Operator From Hell
• TLC — The Learning Channel
• FE — Far End
• IV — Initialization Vector
• HTML — Hyper Text Markup Language
• E&M — ear and mouth (special signaling leads)
• NNM — Network Node Manager
• IS — Information System
• RSS — Really Simple Syndication
• CDA — Command and Data Acquisition
• RT — Radiotelephone
• VC — Virtual Channel
• PDS — Planetary Data System
• ACT — Activity
• LU — Logical Unit
• HDSL — High-bit-rate Digital Subscriber Line
• FR PVC — Frame Relay Permanent Virtual Connection
• LEN — Line Equipment Number
• DID — data item description
• EFS — Encrypting File System
• NIC — Network Interface Controller
• ARQ — Automatic Repeat-reQuest
• MCC — Mission Control Center (JSC)
• IMSI — International Mobile Subscriber Identity
• MOL — Manned Orbiting Laboratory
• EIP — Equipment installation procedure
• DAL — Dedicated Access Line
• ADL — Advanced Distributed Learning
• ADF — automatic document feeder
• ETS — European Telecommunication Standard
• ARC — Army Reuse Center
• ELT — Emergency Locator Transmitter
• AIN — Advanced Intelligent Network
• 100BASE-T4 — 100 Megabits per Second, Baseband, Four-pair Category 3 UTP cables
• CICS — Customer Information Control System (IBM Mainframe Software; Kicks Or C-I-C-S)
• ECP — Encryption Control Protocol
• DCS — Digital Cross-Connect
• TCR — Temperature Coefficient of Resistance
• PIM — Personal Information Manager
• TE — Terminal Equipment

• MOD — Modify
• CNM — Customer Network Management
• DID — Digital Information Display
• DL — Digital Library
• VBR — Variable Bit Rate (ATM)
• QPSK — aeronautical quadrature phase shift keying
• CER — Cell Error Ratio
• MIT — Massachusetts Institute of Technology (U.S.)
• DSLAM — Digital Subscriber Line Access Multiplexer (Module)
• ASARS — Advanced Synthetic Aperture Radar System
• WINS — Windows Internet Name Service
• SL — Single Line
• SPGA — Staggered Pin Grid Array
• MMSI — Maritime Mobile Service Identity
• ATA — Analog Telephone Adapter
• EHF — Extremely High Frequency
• ECM — Electronic Counter Measures
• Y — Yes
• SRS — Software Requirements Specifications
• 10BASE-T — 10 Megabits per second, Baseband, Twisted pair
• CU — Channel Unit
• SPA — Special Prorate Agreement
• NFPA — National Fire Protection Association
• 2W — Two Wire
• ASTD — American Society of Training and Development (Alexandria, Virginia)
• ITP — Interactive Telecommunications Program
• TIA — Telecommunications Industry Association
• FAA — Federal Aviation Agency
• 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)
• AUD — Audit
• FSK — Frequency-Shift Keying
• TDMA — Time Division Multiple Access
• 100BASE-T — 100 Megabits per second, Baseband, Twisted pair
• ATC — Advanced Technology Center
• METRO — Metropolitan
• RT — Response Time
• CAPS — Call Attempts Per Second
• GHZ — Gigahertz
• IRS — Inertial Reference System
• PUK — PIN (Personal Identification Number) Unlocking Key
• IMC — Intermediate Metal Conduit
• SD — Software Development
• BSA — Business Software Alliance
• BTC — Botswana Telecommunications Corporation
• BER — Basic Encoding Rules (ASN.1)
• SDK — Software Development Kit (Microsoft)
• SML — Service Management Layer
• JCL — Job Control Language
• ARG — Argument
• RJ-25 — Registered Jack type 25 (6-wire connector)

• ACF — Access Control Field
• SDLC — Synchronous Data Link Control
• TE — Test Equipment
• OTA — Office of Technology Assessment (U.S.; abolished by Congress, Fall 1995)
• E — Echo Time Zone
• MPEG — Motion Picture Experts Group
• CFV — Call For Vote(s)
• TTY — Teletype Telex Machine
• AM — Activity Manager
• FE — Finite Element
• SCN — Switched Circuit Network
• CB — Common Battery
• FWA — Fixed Wireless Access
• B-ISDN — Broadband Integrated Services Digital Network
• CO — Central Office
• B3G — Beyond Third Generation
• 911 — Emergency Services Phone Number
• LQR — Linear Quadratic Regulator
• NES — Network Encryption System
• EGP — Exterior Gateway Protocol
• TEL — Telephone
• VSAT — Very Small Aperture Terminal (satellite service)
• ABN — Abnormal
• DC — Display Controller
• PS — Product Specification
• SF — Single Frequency
• DDN — U.S. Defense Data Network
• TOA — Time Of Arrival
• RJ-14 — Registered Jack type 14 (2-wire connector)
• PTA — Pakistan Telecommunication Authority
• MX — Mixer
• CDC — Connected Device Configuration
• ODBC — Open Database Connectivity
• BCH — Binary Coded Hexadecimal
• BOD — Bandwidth on Demand
• TI — Time Interval
• PVD — Physical Vapor Deposition
• A — Anode
• SUS — Suspension
• WAIS — Wide Area Information Server
• COMDEX — Computer Dealers Exposition
• LT — Less Than
• COAX — Coaxial
• NSAI — National Standards Authority of Ireland
• Q — Quadrature
• GDM — GSM (Global System for Mobile communications) Data Module
• VT — Virtual Terminal
• APN — An Access Point Name
• 9 — Nine
• HEHO — Head End Hop Off

• PEM — Privacy-Enhanced Mail
• BS — Broadcast Satellite
• ACLR — Adjacent Channel Leakage Ratio
• DM — Domain Model
• TCM — Trellis-Coded Modulation
• NCP — Network Control Protocol
• PIC — Peripheral Interface Controller
• SPA — Software Publishers Association
• BIU — Bus Interface Unit
• CBR — Constant Bit Rate
• E — Echo
• FDL — Facility Data Link
• EIGRP — Enhanced Interior Gateway Routing Protocol
• NCSC — National Computer Security Center (NSA)
• VMS — Virtual Memory System
• LIU — Line Interface Unit
• TSR — Telecommunications Service Request
• VBA — Visual BASIC for Applications
• UP — User Profile
• NPA — Numbering Plan Area
• SDM — Service Delivery Management
• DCN — Disconnect
• VLSI — Very-Large-Scale Integration
• NTP — Network Time Protocol
• SLAM — Scanning Laser Acoustic Microscope
• TDOA — Time Difference Of Arrival
• RMI — Remote Method Invocation
• AP — access point
• SMB — Server Message Block
• EMCON — Electromagnetic Emission Control
• ACAP — Application Configuration Access Protocol
• DCS — Digital Cellular System
• CPS — Cycles Per Second (now Hertz)
• TELECOMMUTE — Telecommuting
• CAM — Content Addressable Memory
• TLK — Talk
• EMS — Element Management System (ATM)
• ADT — American District Telegraph Company
• PE — Probable Error
• KAK — Key-Auto-Key
• DNIC — Data Network Identification Code
• IESG — Internet Engineering Steering Group
• TDM — Time Division Multiplexer
• MLP — Mobile Location Protocol
• AN — Access Node
• DAT — Digital Audio Tape
• DTD — Document Type Definition (XML)
• CS — Convergence Sublayer (ATM)
• HEX — Hexadecimal (base 16)
• AAV — Accountholder Authentication Value

• NOAO — National Optical Astronomy Observatories (Tucson, AZ)
• ORB — Object Request Broker
• RP — Reference Point
• EMS — Enhanced Messaging Service
• NE — North-East
• COPS — Common Open Policy Service
• TTY — teletype terminal
• DPL — Digital Power Line
• B6ZS — Bipolar 6 Zero Substitution
• FEP — Front End Processor
• QDR — Quad Data Rate
• VT — Vacuum Tube
• IRQ — Interrupt Request
• MIS — Management Information Service
• ISOC — Internet Society
• LNP — Local Number Portability
• PM — Phase Modulation
• BHCA — Busy Hour Call Attempt
• SAR — synthetic aperture radar (satellite)
• PMP — Project Management Professional
• TCPA — Telephone Consumer Protection Act
• BSS — Base Station Subsystem
• DTMF — Dual-Tone MultiFrequency
• EFIS — Electronic Flight Information System
• KDC — Kerberos Key Distribution Center
• AWACS — Airborne Warning And Control System
• EIA — Extended Interaction Amplifier
• CDE — Common Desktop Environment
• LRC — Learning Resource Center
• BAN — Base Area Network
• AS — Access System
• DII — Defense Information Infrastructure
• VOA — Voice Of America
• SPM — Scanning Probe Microscope
• DIS — Draft International Standard
• AMSS — Automatic Message Switching System
• PG — Page
• BSS — Basic Service Set
• CQA — Certified Quality Auditor
• JAN — Joint Army-Navy
• TDD — Time Division Duplex
• ASDE — Airport Surface Detection Equipment
• TXM — Transmission X-ray Microscope
• TKIP — Temporal Key Integrity Protocol
• IT — Integration Test
• PC — Peripheral Controller
• ES — Emergency Service
• ATS — Automatic Transfer Switch
• CRBT — Caller Ring Back Tone
• PP — Polypropylene

• DDCMP — Digital Data Communications Message Protocol
• MBWA — Mobile Broadband Wireless Access
• 3GPP — Third Generation Partnership Project
• CTU — Central Terminal Unit
• CVR — Crystal Video Receiver
• IEEE — Institute of Electrical and Electronics Engineers
• CPS — characters per second
• TOVS — TIROS Operational Vertical Sounder
• RADIUS — Remote Authentication Dial-In User Service
• ADB — Apple Desktop Bus
• SAS — Special Access Surcharge
• SITA — Société Internationale de Télécommunications Aéronautiques
• DSS — Digital Signature Standard
• JTF — Joint Task Force
• B2B — Business-to-Business
• 2W — 2-Wire
• SA — Source Address
• BBM — Blackberry Messenger
• OSCAR — Orbiting Satellite Carrying Amateur Radio
• AIT — Automatic Identification Technology
• DS-0 — Digital Signal, Level 0
• FEC — Forward Error Correction
• LISP — List Processing Language
• TCIC — Trunk Circuit Identification Code
• EMEA — Europe, Middle East and Africa
• BTAM — Basic Telecommunications Access Method
• SIM — Subscriber Identity Module
• SZ — Seizure
• AMPS — Advanced Mobile Phone System
• CPC — Continous Packet Compression
• CCNA — Cisco Certified Network Associated
• IAB — Internet Architecture Board
• POE — power over ethernetinjector
• ESP — Encapsulating Security Payload
• CPN — Cisco Powered Network
• OMA — Open Mobile Alliance
• ISM — Industrial, Scientific and Medical
• C — Cost
• DCE — Data Communication Equipment
• DN — Distinguished Name
• SMR — Specialized Mobile Radio
• EM — Electromigration
• VPI — Virtual Path Identifier
• QI — Quality Indicator
• CODEC — Coder/decoder
• VF — Voice Frequency
• DL — Data Link
• OT — Office of Telecommunications
• TTY — Text Teletype
• FRS — Family Radio Service

• FEP — Front-End Processor
• DER — Distinguished Encoding Rules
• NIU — Network Interface Unit
• DMI — Distributed Management Interface
• FRS — Frame Relay Service
• DEMUX — Demultiplexer
• MAI — Multiple Access Interference
• RDS — Rate Determining Step
• NRPB — National Radiological Protection Board
• SOS — Save Our Souls (Help!)
• NA — Network Adapter
• TMS — Time Management System
• DDL — Digital Data Link
• NSS — Network Switching Subsystem
• JRE — Java Runtime Environment
• MDM — Mobile Device Management
• MIDP — Mobile Information Device Profile
• FMC — Fixed Mobile Convergence "Mobile UC or Unified Communications over Wireless"
• PDT — Portable Data Terminal
• PU — Physical Unit (IBM)
• PROM — Programmable Read-Only Memory
• DPSK — Differential Phase Shift Keying
• RAU — Radio Access Unit (Army)
• TRMM — Tropical Rainfall Measuring Mission (US-Japan)
• EST — Establish
• SLV — Satellite-Launch Vehicle
• IPS — InPlane Switching
• IAT — Integrated Access Terminal
• DVB — Digital Video Broadcasting
• COMINT — Communications Intelligence
• SWAP — Shared Wireless Access Protocol
• BS — Backing Store
• DSN — Defense Switched Network
• BIS — Business Information System
• CB — Citizens' Band
• CAP — Capability
• RDI — Remote Defect Indicator (UNI Fault Management)
• CGA — Carrier Group Alarm
• HLR — Home Location Register
• RLU — Remote Line Unit
• TSB — Telecommunication Standardization Bureau
• WHT — Walsh-Hadamard Transform
• SNA — System Network Architecture
• SDP — Software Development Plan
• CBWFQ — Class Based Weighted Fair Queueing
• AMR — Automated meter reading also known as Automatic Meter Reading
• SG — Signaling Gateway (IETF)
• SPD — Serial Presence Detect
• AC — Area Code
• LASA — Large Aperture Seismic Array

• IRC — International Record Carrier
• CSPDN — Circuit Switched Public Data Network
• MSRN — Mobile Station Roaming Number
• DPL — Digital Private-Line
• XPS — X-Ray Photoelectron Spectroscopy
• LATA — Local Access and Transport Area
• DUA — Directory User Agent
• DDD — Direct Distance Dialing
• TSE — Toronto Stock Exchange
• SPX — Sequenced Packet Exchange
• PSS — Performance Support System
• LD — Laser Diode
• ACE — Adaptive Communication Environment
• TRLR — Trailer
• PVC — Permanent Virtual Connection
• WTLS — Wireless Transport Layer Security
• TL1 — Transaction Language 1
• MV — Motion Vector
• CAL — Calorie
• SB — Switchboard
• DMS — Data Management System
• TDD — Telecommunications Device for the Deaf
• FSAI — Fiber Serving Area Interface
• PCI — Personal Computer Interface
• FLM — First Line Maintenance
• NDVI — Normalized Difference Vegetation Index
• CSA — Canadian Standards Association (like UL)
• TFTP — Trivial File Transfer Protocol (ATM)
• FAS — Frame Alignment Signal
• OOP — Object-Oriented Programming
• CIAC — Computer Incident Advisory Capability
• DPDU — Data Protocol Data Unit
• FITL — Fiber-In-The-Loop
• IEC — Interexchange Carrier
• HFC — Hybrid Fiber/Coaxial network
• LAG — Link Aggregation Group
• CRLF — Carriage-Return Line-Feed
• FOSE — Federal Office Systems Exposition
• GMRS — General Mobile Radio Service
• O/S — Operating System
• EULA — End User License Agreement (usually in reference to software)
• ADN — Abbreviated Dialing Number
• CAMA — Centralized Automatic Message Accounting
• CI — Common Interface
• CGSA — Cellular Geographic Service Area
• ISO — Independent System Operator (US) (see also TSO) Responsible for grid management, but does not own assets. (electricity)
• OD — Outside Diameter
• E — Electra
• ASA — Acoustical Society of America
• NAT — Network Address Translation

• BCH — Bose-Chaudhuri-Hocquenghem Coding
• FEXT — Far-End Cross Talk
• FH — Frequency Hopping
• FTAM — File Transfer Access and Management
• AUI — Attachment Unit Interface
• AMPS — Advanced Mobile Phone Service (cellular phone standard)
• TRS — Trunked Radio Systems
• MTS — Message Transfer System
• FRAD — Frame Relay Access Device
• WORM — Write-Once, Read-Many
• CP — Change Proposal
• SIL — Silence
• STD — Subscriber Trunk Dialing
• RMS — Resource Management System
• DW — Deep Water
• CS-PDU — Convergence Sublayer - Protocol Data Unit
• SLIC — Subscriber Line Interface Circuit
• APDU — Application Protocol Data Units
• JDK — Java Development Kit
• TAD — Telephone Answering Device
• AIF — Audio Interchange Format
• RJE — Remote Job Entry
• IDF — Independent Distribution Frame
• AFOSR — Air Force Office Of Scientific Research(USA)
• SRM — Scalable Reliable Multicast
• VLAN — Virtual Local Area Network
• NAK — Negative Acknowledge
• CONUS — Contiguous United States
• GBT — Ground Based Tower
• CSC — Common Signaling Channel
• VRML — Virtual Reality Modeling Language
• SIA — Securities Industry Association
• MEID — Mobile Equipment Identifier
• BNC — Bayonet Neill-Concelman
• SM — Service Module
• DAP — Distributed Array Processor
• BSI — British Standards Institution
• SIL — Solid Immersion Lens
• RPV — Remotely Piloted Vehicle
• LSI — Large Scale Integration -> VLSI
• EMI — Electro-Magnetic Interference
• IOC — Inter-Office Channel
• SDU — Signal Distribution Unit
• ER — Extended Range
• DII — Dynamic Invocation Interface
• T — Temperature
• WWAN — wireless wide-area network
• CCIR — International Radio Consultative Committee (French Acronym)
• FTTC — Fiber To The Curb光纤到路边
• NREN — National Research and Education Network

• RCC — Radio Common Carrier
• SMI — Structure of Management Information
• OCC — Occupancy
• CAM — Common Access Method
• BMEWS — Ballistic Missile Early Warning System (bee-mews)
• PTP — Point to Point Transmission Service (electricity)
• ADC — Access Deficit Charge
• CIRC — Cross-Interleaved Reed-Solomon Code
• YABA — Yet Another Bloody Acronym
• FDTD — Finite Difference Time Domain
• HSCSD — High-Speed Circuit-Switched Data
• SD — Speed Dial
• VTS — Vessel Traffic Service
• ADC — Administration Center
• ALT — Accelerated Life Test
• SYM — Symmetric
• TC — Transmission Convergence (ATM)
• DGPT — Directorate General of Posts and Telecommunications
• DHD — Dial Home Device
• EU — End User
• 1FB — Single line, Flat Business rate;
• CMOS — Complementary Metal Oxide Semiconductors
• 4W — Four-Wire
• IPS — Instructions Per Second
• BA — Behaviour Aggregate
• ETF — Early Termination Fee
• IRTF — Internet Research Task Force
• OXCO — Oven-Controlled Crystal Oscillator
• L2TPV3 — Layer 2 Tunneling Protocol Version 3
• RISC — Reduced Instruction Set Computing
• RQMTS — Requirements
• CP — Call Processing
• EIR — Equipment Identity Register
• SMDS — Switched Multimegabit Data Service (ATM)
• EECM — End-to-End Call Manager
• TTL — ToS and Time-to-Live
• SQ — Service Quality
• COM — Comedy Central
• DTN — Data Transfer Network
• DSCP — Differentiated Services Code Point
• SAI — Serving Area Interface
• SDP — Session Description Protocol
• VG — Voice Grade
• OSS — Operations Support System
• BSS — Base Station System
• SSRC — Synchronization Source
• CGA — Color Graphics Adapter
• SPIN — Service Provider Identification Number
• TSO — Telecommunications Service Order
• DCS — Data Collection System (NOAA Polar Orbiting Satellites)

• IMP — Interface Message Processor
• AP — Action Point
• DISN — Defense Information Systems Network
• LPD — Low Probability of Detection
• CLK — Clock
• CE — Channel Element
• LSF — Line Spread Function
• CNG — comfort noise generation
• PBT — Polybutylene Terephthalate
• POP — Post Office Protocol
• BLER — Block Error Rate
• LT — Line Termination
• SONET — Synchronous Optical Network
• C — Collector
• CIS — Computer and Information Science
• BMS — Business Management System
• SDSL — Symmetric Digital Subscriber Line
• OBC — Onboard Computer
• NAS — Network-Attached Storage
• DACS — Digital Access Cross-connect System
• COO — Cell of Origin
• SCU — System Control Unit
• RSS — Radio Service Software (Motorola)
• RACH — Random Access Channel
• CS — Central Station
• BELLCORE — Bell Communications Research, Inc.
• DPCM — differential pulse code modulation
• MCP — Microsoft Certified Professional
• TRS — Telecommunications Relay Service
• P — Priority
• RNX — Restricted Numeric eXchange
• ACSE — Association Control Service Element
• WK — Week
• FEA — Finite Element Analysis
• DDU — Disk Drive Unit
• OSP — Outside Plant
• RAU — Remote Access Unit
• WAR — Weekly Activity Report
• SAF — System Access Fee
• GBPS — Gigabits per second
• WDN — Wireless Developer Network
• ANSI-41 — ANSI standard for mobile management
• SVC — Switched Virtual Circuit (ATM)
• TIFF — Tag Image File Format
• IPCP — Internet Protocol Control Protocol
• LOO — Likelihood of Occurrence
• CMIP — Common Management Information Protocol (ATM)
• SMPTE — Society of Motion Picture and Television Engineers, Inc.
• ASYNC — Asynchronous
• 4GL — Fourth-Generation Language

• ACC — Area Control Center
• CC — Country Code
• EBCDIC — Extended Binary-Coded Decimal Interchange Code
• OTDOA — Observed Time Difference of Arrival
• PAM — Payload Assist Module
• DTI — Digital Trunk Interface
• ODS — Operational Data Store (knowledge management)
• TOP — technical/office protocol
• ACP — Access Control Point
• VHSIC — Very High-Speed Integrated Circuit
• WAYP — White and Yellow Pages
• TAM — Telephone Answering Machine
• SSM — Spread Spectrum Modulation
• IPVX — Internet Protocol version X
• ETSI — European Telecommunications Standard Institute
• AVR — Automated Voice Response
• MHO — My Humble Opinion
• CAVE — Cellular Authentication and Voice Encryption Algorithm
• SN — Stock Number
• S/D — Source/Drain
• 1-ESS — x-ESS series of Electronic Switching Systems
• FMS — Fraud Management System
• ASN.1 — Abstract Syntax Notation One
• DISA — U.S. Defense Information Systems Agency
• NII — National Information Infrastructure (USA)
• IAD — Integrated Access Device
• SISIR — Singapore Institute of Standards and Industrial Research
• ESCA — photoelectron spectroscopy for chemical analysis
• NF — Noise Factor
• DL — Definition List
• EMR — Electromechanical Relay
• ROW — Rest Of World
• MH — Message Handler
• CVD — Chemical Vapor Deposition
• GSM — Groupe Speciale Mobile
• DVMRP — Distance Vector Multicast Routing Protocol
• ARSR — Air Route Surveillance Radar
• MLM — Multi-Longitudinal Mode
• HSPA — High Speed Packet Access
• DRFM — Digital Radio-Frequency Memory
• SN — Service Number
• WSDL — Web Services Description Language
• ASD — Alternative Service Delivery
• FOD — Fax on Demand
• TUR — Trunk Utilization Report
• STN — Station
• FDD — Frequency Division Duplex
• ABM — Asynchronous Balanced Mode
• UMA — Unlicensed Mobile Access
• WE — Western Electric

• LDN — Local Directory Number
• DSI — Digital Speech Interpolation
• CT — Computer Terminal
• SRR — Search and Rescue Region
• V — Variable
• MSW — Most Significant Word
• VPA — Valid Peripheral Address
• 4 GIG — 4 Giga Intellectual Gadget
• MUSIC — MUltiple SIgnal Classification
• AWT — Agence Wallonne des Télécommunications
• FGA — Feature Group A
• UART — Universal Asynchronous Receiver/Transmitter
• ST — Such That
• CIP — Carrier Identification Parameter
• IG — Interface Group
• UAT — Universal Access Transceiver
• OML — Object Model Library
• DC — Device Control
• TAX — Trunk Automatic Exchange
• IPM — Inches Per Minute
• AF — Assured Forwarding
• OSF — Open Software Foundation
• VESA — Video Electronics Standards Association
• SFX — Special Effects
• RECON — Reconnaissance
• IMAP — Internet Mail Access Protocol
• NDS — Novell Directory Services
• TOMS — Total Ozone Mapping Spectrometer (satellite Instrument)
• SSM — Synchronization Status Message
• BOSS — Binary Object Storage System
• RICK — Repeater Interface Communications Kit
• 2G — Second Generation Wireless Systems
• DFG — difference-frequency generation
• RTC — Real-Time Control
• CLDC — Connected Limited Device Configuration
• LDP — Label Distribution Protocol
• CAC — Connection Admission Control (Asynchronous Transfer Mode)
• FXS — Foreign Exchange Subscriber
• ECM — Error Correction Model
• BAN — Building Area Network
• EBS — Electron Bombarded Silicon
• ALB — Analog Loopback
• CGI — Computer Graphics Interface
• ABBR — Abbreviation
• LCR — Least Cost Routing
• MA — Maintenance Action
• ASE — Application Service Element
• DCA — Dynamic Channel Assignment
• LIF — Logical Interchange Format
• FDI — Feeder Distribution Interface

• ET — Electronic Transmission
• SCPC — single channel per carrier
• PTP — Point To point Protocol
• SWBD — Switchboard
• IEEE-CS — Institute of Electrical and Electronics Engineers Computer Society
• MPI — Minimum Picture Interval
• IEEE-SA — Institute of Electrical and Electronics Engineers - Standards Association
• CND — Calling Number Display
• 3-D — 3-Dimensional
• LFACS — Loop Facility Assignment and Control System
• COT — Central Office Terminal
• 4G — Fourth Generation Wireless Systems
• RSL — Restricted Service License
• MAJ — Major
• PLL — Phase Locked Loop
• HTML — Hyper-Text Markup Language
• EVA — Electronic Video Agent
• EA — Extended Address Field Bit
• EDFA — Erbium-Doped Fiber Amplifier
• AAS — advanced automation system (FAA)
• CLETS — California Law Enforcement Telecommunication System
• CPG — Converged Packet Gateway
• SIMT — Système interbancaire marocain de télécompensation
• FGD — Feature Group D
• DDI — Direct Dialing Incoming
• CGI — Cell Global Identity
• VSAM — Virtual Storage Access Method
• PMT — Program Management Team
• WDA — Wireless Digital Assistant
• CNG — Fax Calling Tone
• ISG — Information Systems Group
• CHTML — Compact Hypertext Markup Language
• LRC — Longitudinal Redundancy Check
• PARC — Palo Alto Research Center
• RX — Receive
• WCDMA — Wideband Code Division Multiple Access
• CFNRY — Call Forwarding on No Reply
• MSDP — Multicast Source Discovery Protocol
• MC — Maintenance Control
• EBIC — Electron Beam Induced Current
• CIP — Channel Interface Processor
• REA — Rural Electrification Administration (US)
• DM — Differential Mode
• ADCCP — Advanced Data Communication Control Procedures
• PDL — Positioning Data Link
• PIC — Programmable Interrupt Controller
• DLP — Data Link Processor
• FECN — Forward Explicit Congestion Notification (ATM)
• AOS — Alternate Operator Service
• CCNA — Cisco Certified Network Administrator

• WSFL — Web Services Flow Language
• RGN — Region
• CMRS — Commercial Mobile Radio Service
• INE — Intelligent Network Element
• TCP/IP — Transmission Control/Internet Protocol
• CDM — Conceptual Data Model
• INTELSAT — International Telecommunications Satellite
• EGSM — Extended Global System for Mobile Communications
• PNP — Plug-and-Play
• ASAR — Advanced Synthetic Aperture Radar 
• NTDS — Naval Tactical Data System
• MITI — Ministry of International Trade and Industry
• 3G — 3rd Generation Wireless Format
• SETI — Search for Extraterrestrial Intelligence
• SIP — Session Initiation Protocol
• ASN.1 — Abstract Syntax Notation 1
• SIM — Subscriber Identification Module
• UTP — unshielded twisted pair
• ACA — Adaptive Channel Allocation
• GI — Graded-Index
• EDC — Electronic Dispersion Compensator
• CCR — Customer Controlled Reconfiguration (Sprint)
• CTI — Computer Telephony Integration
• CRB — Cramer-Rao Bound
• RMON — Remote Monitoring
• RSS — root-sum-square
• CALEA — Communications Assistance for Law Enforcement Act
• DARTS — Design Approach for Real-Time Systems
• SSMA — Spread-Spectrum Multiple Access
• ARM — Asynchronous Response Mode
• ISI — Intersymbol Interference
• VN — Virtual Network
• MGC — Multimedia Gateway Controller
• FSK — Frequency Shift Keying
• DLL — Digital Local Line
• CODASYL — COnference on DAta SYstems Languages
• RDMA — Remote Direct Memory Access
• TDRSS — Tracking and Data Relay Satellite System
• SFN — Single Frequency Network
• BOM — Bit-Oriented Message
• NTU — Network Termination Unit
• LSW — Least Significant Word
• CRTS — Cellular Radio Telecommunications Service
• RDBMS — Relational Data Base Management System (Oracle)
• ANC — Access Network Controller
• ACF — Advanced Communications Function (IBM)
• DAC — Digital-To-Analog Converter
• ILEC — Incumbent Local Exchange Carrier
• LIS — Lightning Imaging Sensor
• ILD — International Long Distance

• FNN — Full National Number
• BCDIC — Binary Coded Decimal Interchange Code
• CPC — Calling Party Control
• LBR — Low Bit Rate
• DPT — Dynamic Packet Transport
• CIP — Continuous Improvement Program
• CSU — Channel Service Unit
• IRF — Impulse Response Function
• MA — Message Analysis
• MMC — Microsoft Management Console (Microsoft)
• EIR — Excess Information Rate
• TELNET — Telecommunications Network Protocol
• WARC — World Administrative Radio Conference
• DTU — Data Transfer Unit
• DTAP — Direct Transfer Application Process
• ULL — Unbundled Local Loop
• DCF — Distributed Coordination Function
• IPLC — International Private Leased Circuit
• FAC — Forced Authorization Code
• EMF — Event Management Framework
• AAL5 — ATM (Asynchronous Transmission Mode) Adaptation Layer 5
• PSN — Packet Switched Network
• RXQUAL — Received Signal Quality
• NCC — Network Control Center (GSFC)
• NCAR — National Center for Atmospheric Research (US)
• WTS — Wireless Telecommunications Symposium
• TEI — Terminal Endpoint Identifier
• IWF — Interworking Function
• CRV — Call Reference Value
• VPWS — Virtual Private Wire Service
• ALI — Automatic Location Information
• W-CDMA — Wideband Code Division Multiple Access
• L2TP — Layer 2 Tunneling Protocol
• VTAM — Virtual Telecommunication Access Method
• VQV — Voice Quality Value
• TPC — The Phone Company
• FTTK — Fibre To The Kerb
• KSU — Key Service Unit
• ICL — Inserted Connection Loss
• ELFEXT — Equal-Level Far-End Cross-Talk
• SSN — Switched Service Network
• UDP — Up Down Pair
• GAN — Global Area Network
• CAM — Computer-Aided Manufacturing
• VLSI — Very Large-Scale Integration
• LR-WPAN — Low-Rate Wireless Personal Area Network
• LQC — Line Quality Control
• FC — Frame Control
• LANE — Local Area Network Emulation
• PIM — Protocol Independent Multicast

• FCA — Fixed Channel Allocation
• DUV — Deep Ultraviolet
• MP — Modulation Parameter
• SE — Southeast
• BSC — Bi-Synchronous Communications
• REPT — Report
• RADIUS — Remote Authentication dial In User Service
• CPH — Call Party Handling
• CLCC — Ceramic Leaded Chip Carrier
• CLEC — Competitive Local Exchange Carrier
• DIV — Divisionsion
• CPOP — Circuit Precedence Over Packet data
• ILETS — International Law Enforcement Telecommunications Seminar
• DFE — Design For Environment
• LS — Loop Start
• PACS — Personal Access Communications System
• TDWR — Terminal Doppler Weather Radar
• CV — Coding Violation
• DPA — Distributed-Power Architecture
• SCCS — Switching Control Center System
• CPE — Customer Premise Equipment
• AWG — arrayed waveguide grating
• RCP — Right-Hand Circular Polarization
• GRUB — Greedy Reclamation of Unused Bandwidth
• ALOC — Average Length Of Call
• PSO — Professional Services Organization
• TACSAT — Tactical Satellite
• LRQ — Location Request
• NWK — Network
• RDT — Recall Dial Tone
• SSAP — Source Service Access Point
• NRP — Network Resource Planning
• BIS — Brought Into Service
• CCCH — Common Control Channel
• ETN — Electronic Tandem Network
• DMT — Discrete Multi-Tone Technology
• NCP — Network Control Program
• CIC — Carrier Identification Code
• VPX — Virtual Path Cross-Connect
• DAS — Data Acquisition System
• VCI — Virtual Channel Identifier
• STMR — Sidetone Masking Rating (telecommunications)
• DXC — Digital Cross Connect
• WSP — Wireless Service Provider
• IV&V — independent verification and validation
• DA — deca
• DLCI — data link connection identifier
• SS1 — Signalling System 1 (500/20 Hz tones)
• RCU — Radio Control Unit
• FOIP — Fax Over Internet Protocol

• DQDB — Distributed Queue Dual Bus
• GDK — GIMP (GNU Image Manipulation Program) Drawing Kit
• CTIA — Cellular Telecommunications Industry Association
• BY — Busy
• COC — Central Office Connection
• IR — International Roaming
• NCF — Network Control Facility
• DNSIX — Defense Network Security Information Exchange
• TACACS — Terminal Access Controller Access Control System
• EEROM — Electronically Erasable Read-Only Memory
• PTT — Push to Talk Technology
• DNC — Do Not Call
• WFA — Wait for Answer
• IPR — Intellectual Property Right
• # — Number sign, octothorp; special function key
• UBR — Unspecified Bit Rate
• MTD — Moving Target Detection
• ATS — Air Traffic Services
• CACH — Call Appearance Call Handling
• DXF — Data Exchange Format
• CMA — Communications Management Association
• URN — Uniform Resource Namespace
• UMTS — Universal Mobile Telecommunications Service
• ADM — Administration Building
• SCR — Sustainable Cell Rate
• OMF — Object Management Framework
• FTNS — Fixed Telecommunications Network Services
• BSA — Basic Service Area
• ESPN — Entertainment and Sports Programming Network
• INSAT — Indian National Satellite
• F — Frequency
• AMA — automatic message accounting
• DICOM — Digital Imaging and Communications in Medicine
• BHCA — Busy Hour Call Attempts
• YA — Yet Another
• LH — Link Handler
• 3G — Third Generation (mobile communication system)
• IPRC — Intellectual Property Rights Committee
• FTTP — Fiber To The Premises
• B-CPE — Broadband Customer Premises Equipment
• BDE — Borland Database Engine
• BIND — Berkeley Internet Name Domain
• PD — Pulse Duration
• COFA — Change Of Frame Alignment
• ATS — Abstract Test Suite
• FCA — Free Carrier Alongside
• WNMS — Wireless Network Management System
• CSIRO — Commonwealth Scientific and Industrial Research Organization
• VSAT — Very Small-Aperture Terminal
• FMR — Follow Me Roaming

• MSC — Mobile Switching Center
• CCITT — Comit? Consultatif International T?l?graphique et T?l?phonique
• RTB — Retransmission Buffer
• SMS — Service Management System
• MR — Mobile Router
• LB — Local Battery
• SAT — Satellite
• TLT — Test Loop Translator
• FEM — Finite Element Method
• PTO — U.S. Patent And Trademark Office
• PSDN — Public Switched Digital Network
• TCB — Telecommunication Certification Body
• TD — Transmit Data
• DOCSIS — Data over Cable Service Interface Specification
• SRL — Singing Return Loss
• 2G — Second generation cellular
• LIM — Line Isolation Monitor
• BT — Burst Tolerance
• ECS — Environmental Control System (Subsystem)
• L2F — Layer 2 Forwarding protocol
• SCH — Synchronization Channel
• CAR — committed access rate
• ERL — Echo Return Loss
• WVOIP — Wireless Voice over Internet Protocol
• NC — Network Channel
• GERAN — GSM (Global System for Mobile communications) Edge Radio Access Network
• RADINT — Radar Intelligence
• UPT — Universal Personal Telecommunications
• NE — Network Element
• DNU — Do Not Use
• HFC — Hybrid Fiber Coaxial
• CPAP — Customer Premises Access Profile
• PTT — Push to Talk Testing
• BUFR — Binary Universal Form for the Representation (of data)
• WTP — Wireless Transaction Protocol
• BSID — Base Station Identity
• VADB — Virtual Auto Dial Backup
• OOK — On/Off Keying
• LP — Line Pair
• TBPS — Terabits Per Second
• FTS — Federal Telecommunications System
• RDT — Remote Digital Terminal
• ZCZ — Zero Correlation Zone
• QOI — Quality of Information
• PLCP — Physical Layer Convergence Procedure
• NT — New Technology, also Windows NT
• JISC — Japanese Industrial Standards Committee
• B8ZS — Binary Eight Zero Substitution
• TMSI — Temporary Mobile Subscriber Identity
• TM — Thematic Mapper (Landsat)

• ESN — Electronic Serial Number
• OWS — Operator Work Station
• SN — Switching Network
• TT — Text-Telephone
• FIOS — Fiber Optic Services
• NW — North West
• MAP — Mobile Application Part
• BDSL — Broadband Digital Subscriber Line
• OSA — Open System Architecture
• BT — Bluetooth Tablet
• BAF — Bellcore AMA (Automatic Message Accounting) Format
• TDR — Time-Domain Reflectometry
• MTI — Moving Target Indicator
• CCLC — Carrier Common Line Charge
• DTL — Defense Telephone Link
• FPS — Framing Pattern Sequence
• MBE — Molecular Beam Epitaxy
• DCAS — Downloadable Conditional Access System
• LCP — Local Control Point
• CEPT — Conférence Européenne des Administrations des Postes et des Télécommunications
• NSAP — Network Service Access Point
• ATSC — Advanced Television Systems Committee
• MTA — Message Transfer Agents (Internet)
• DPDT — Double-Pole Double-Throw
• DTE — Digital Terminal Equipment
• DOD — Direct Outward Dialing
• LAAS — Local Area Augmentation System
• LLA — Link Level Access
• TU — Transmission Unit
• EDSX — Electronic Digital Signal Cross-Connect
• DPBX — Digital Private Branch Exchange
• TCA — Threshold Crossing Alert
• STU — Secure Telephone Unit
• MMDS — Multichannel Multipoint Distribution Service
• LUNT — Line Unit Network Termination
• ISMI — International mobile subscriber identity
• CID — Craft Interface Device
• LCF — Location Confirm
• M/W — MicroWave
• ADPCM — Adaptive Differential Pulse Code Modulation
• MLA — Modern Language Association
• ET — Exchange Terminal
• OMP — Open Management Platform
• DE — Discard Eligibility (ATM)
• EFCI — Explicit Forward Congestion Indication (ATM)
• MF — Multiple Frequency
• ESCON — Enterprise System Connection
• CCP — Compression Control Protocol
• FI — Format Identifier
• UIT — Union Internationale des Télécommunications

• COAM — Customer Owned And Maintained
• DRQ — Disengage Request
• MFC — Multi-Frequency Code
• ENV — Environment
• DEM — Digital Elevation Model
• OLS — Optical Line System
• EV — electronvolt
• EM — Element Manager
• SNIX — Single Noise Interference Xterminator
• VISSR — visible and infrared spin scan radiometer (GOES)
• PNP — Positive-Negative-Positive
• UNI — User-Network Interface
• VOB — Voice Over Broadband
• TSC — Test System Controller
• CRS — Cell Relay Service
• IBSS — Independent Basic Service Set
• ADPC — Automatic Data Processing Center
• CSR — Customer Service Report
• RIPE NCC — Reseaux IP Europeens Network Coordination Centre
• ACF — Access Coordination Function
• SCM — Single-Carrier Modulation
• TDM — Time Division Multiplexing
• TBCD — Telephony Binary Coded Decimal
• SCR — System Change Request
• USA — Underground Service Alert
• CSDU — Core Service Data Unit
• 3GPP — Third-Generation Partnership Project
• MFLOPS — Millions of Floating Point Operations per Second
• GTP — GPRS (General Packet Radio Service) Tunneling Protocol
• 3G HSPA — Third-Generation High-Speed Packet Access
• ARFA — Allied Radio Frequency Agency
• CTO — Commonwealth Telecommunications Organisation
• CON — Concentrator
• VSM — Vestigial Sideband Modulation
• DIL — Direct Inward Line
• SA — Selective Availability (on GPS transmissions)
• TC — Technical Committee (HL7)
• NDIS — Network Driver Interface Specification (Microsoft Windows NT)
• CES — Circuit Emulation Service
• CTE — Computer Telephony Engineer
• DSSSL — Document Style Semantics and Specification Language
• SRA — Seamless Rate Adaptation
• CDV — Cell Delay Variation(ATM)
• BATM — Basic Telecommunication Access Method
• FFH — Fast Frequency Hopping
• RFR — Radio Frequency Radiation
• PTT — Push to Talk Taster
• LI — Length Indicator
• MMM — Mobile Media Mode
• APPC — Advanced Program-to Program Communications

• MGCP — Multimedia Gateway Control Protocol
• EPP — Enhanced Parallel Port (PC)
• DAC — Digital to Analog Converter-Audio
• * — Star, special function key
• FAT — Final Acceptance Testing
• CBQ — Class-Based Queuing
• NMC — Network Management Center
• MRT — Medical Response Team
• CLD — Cross-Layer Design
• CSAR — Combat Search and Rescue
• GS — Ground Start
• LOP-P — Loss Of Pointer - Path
• CERN — Conseil Europeen Pour La Recherche Nucleaire
• ALI — Automatic Location Identifier
• LAPB — Link Access Protocol-Balanced
• PUC — Public Utility Commission (electricity)
• CAMEL — Customized Applications for Mobile-network Enhanced Logic
• NTE — Network Terminating Equipment
• LSC — Link State Control
• SMS — System Management Server
• CC — Composite Clock (SONET)
• LCAS — Link Capacity Adjustment Scheme
• WFG — Wireless Firewall Gateway
• CDA — Communications Decency Act's
• ATTRA — Appropriate Technology Transfer for Rural Areas
• CASE — Computer-Aided Software Engineering
• FIFO — first-in, first-out
• DDLD — Direct Dial Long Distance
• DDU — Digital Data Unit
• DL — Downlink Message
• DOR — Detailed Outage Report
• RRC — Root Raised-Cosine
• HDTV — High-Definition Television
• DXI — Data Exchange Interface
• MEAS — Measure
• FAW — Frame Alignment Word
• MDN — Mobile Directory Number
• ECTF — Enterprise Computer Telephony Forum
• STM — Scanning Tunneling Microscopy
• F/W — Firmware
• UTL — Utility
• LEED — Low-energy Electron Diffraction
• DECT — Digital Enhanced Cordless Telecommunication
• CSR — Customer Service Request
• TP — Transition Point
• 4WAI — Four-Wire Analog Interface
• SPID — Service Profile Identifier
• ALCAP — Access Link Control Application Protocol
• ATU-C — ADSL (Asymmetric Digital Subscriber Line) Transceiver Unit - Central office end
• VOB — Versioned Object Base

• VDR — Voice Digitization Rate
• UCF — Unregistration Confirm
• PDSO — Packet Data Security Overlay
• USF — Universal Service Fund
• SPE — Synchronous Payload Envelope
• DLU — Digital Line Unit
• GTB — Global Telecom Brokers
• BABT — British Approvals Board for Telecommunications
• PSLV — Polar Satellite Launch Vehicle (Indian Space Research Organization; India)
• AT — Attenuation
• VNS — Virtual Network System
• SCORM — Shareable Content Object Reference Model
• SR — Slow Release
• DS-3 — Digital Signal, Level 3
• DMS — Defense Messaging System
• EEHO — Either End Hop Off
• NAP — Network Access Point
• MAU — Multistation Access Unit
• LMT — Lightwave Microcell Transceiver
• IVP — Integrated Voice Protocol
• FLL — Fixed-Loss Loop
• CFOT — Certified Fiber-Optic Technician
• CRBT — Color Ring Back Tone
• TCC — Transmission Control Code
• WAE — Wireless Application Environment
• ETSI — European Telecommunications Standards Institute
• EC — Equipment Controller
• WIN — Wireless Intelligent Network
• CCA — Carrier-Controlled Approach
• PJC — Pointer Justification Count
• IDLC — Integrated Digital Loop Carrier
• JWP — Joint Working Party
• CAAS — Communications-as-a-Service
• GMSS — Global Mobile Satellite System
• WTNM — Working Telephone Number Management
• MSI — Maritime Safety Information
• LRM — Long Reach Multimode
• RP — Radio Port
• ETOC — Electronic Table of Contents
• BHCC — Busy Hour Call Completions
• SMSC — Short Message Service Center
• TP — Telephone Pole
• PY — person-year
• DLT — Delete
• DCS — Defense Communications System
• LSAP — Link Service Access Point
• DBRNC — deciBel Relative to Noise in a Circuit
• CAPTAIN — Character And Pattern Telephone Access Information Network
• DPNSS — Digital Private Network Signaling System
• S/N — Signal-to-Noise ratio

• IS 41 — Interim Standard 41 (Inter-Cellular Network Communication Protocol)
• RADARSAT — Radar Satellite
• NAU — Network Addressable Unit
• FDOA — Frequency Difference Of Arrival
• 4WA — Four Wire Analog
• CDV — Compressed Digital Video
• LN — Line
• PCCA — Portable Computer Communications Association
• P2P — Person-to-Person
• WSA — Wireless Security Auditor
• RPCU — Radio Port Control Unit
• SDNS — Secure Data Network System
• VR — Virtual Router
• IDCP — Internet Device Control Protocol
• FMS — Fixed Mobile Substitution
• B-ISDN — Broadband ISDN
• MPU — Main Processor Unit
• SMMR — Scanning Multichannel Microwave Radiometer
• BB — Blackberry
• SSP — Security Service Provider
• CALS — Computer Aided Acquisition and Logistic Support
• DUN — Dial-Up Networking
• STM — Synchronous Transfer Mode
• NLM — NetWare Loadable Module
• TRIG — Trigger
• TSDU — Transport Service Data Unit
• GSTN — General Switched Telephone Network
• BT — Back Trace
• VPC — Virtual Path Connection (ATM)
• DECCO — DISA Defense Commercial Communications Office
• BPSK — Binary Phase-shift Keying
• FGDC — Federal Geographic Data Committee's
• KEK — Key Encrypting Key
• EST — Electroshock Therapy
• LIDB — Line Information DataBase
• MAG — Mobile Access Gateway
• ECS — Encryption Control Signal
• ARPT — Autorité de Régulation des Postes et Télécommunications
• TNI — Telephone Network Interface
• QS — Quasi-Synchronous
• TCM — Time Compression Multiplexer
• IBS — In-Building Solutions
• ACU — Automatic Calling Unit
• TPS — Telephone Preference Service
• NESC — National Electrical Safety Code
• AIS-L — Alarm Indication Signal - Line
• SEM — Scanning Electron Microscopes
• BWX — Broadband Wireless Exchange
• PCS — Personal Communications Services
• BIC — Bus Interface Controller

• LORAN — Long Range Aid to Navigation System
• DMT — Discrete Multi-Tone
• ZD — Zero Defects
• PHY — Physical Layer
• ESF — Extended Super Frame (ATM)
• WFA — Work Force Administration
• FEAC — Far End Alarm and Control
• IDCU — Integrated Digital Carrier Unit
• BTS — Base Transceiver Station (cellular)
• PSK — Phase Shift Key
• NPSI — Network Packet Switching Interface
• MTP — Message Transfer Part
• AFPS — Automatic Facility Protection Switching
• X — X Window System
• CLP — Cell Loss Priority (ATM)
• ATB — Above-Ground Telecommunications Backbone
• CBMS — Computer-Based Message System
• DNI — Data Network Interface
• VOFR — Voice Over Frame Relay
• DPST — Double-Pole Single-Throw
• N-AMPS — Narrowband Advanced Mobile Phone System
• SAR — Segmentation and Reassembly (ATM)
• CAS — Column Address Strobe
• NRZ — Nonreturn To Zero
• CDM — Configuration Data Manager
• NICT — National Institute of Information and Communications Technology
• ARD — Automatic Ring Down
• CSTA — Computer Supported Telecommunications Applications
• EA — expedited acknowledgement
• RTC — Right to Carry
• ACM — Address Complete Message
• LMS — Location and Monitoring Service
• RAD — Recorded Announcement Device
• LCGN — Logical Channel Group Number
• VSC — Vertical Service Code
• ANAC — An Automatic Number Announcement Circuit
• QPM — QoS (Quality of Service) Policy Manager
• LSP — Label Switched Path
• NSE — Network Software Environment
• VLF — Vertical-Laminar-Flow
• PLE — Path Length Efficiency
• DMT — Digital-Discrete Multi-Tone
• DNA — Do Not Answer
• DOD — Dial on Demand
• P&A — Privacy and Authentication
• EC — Entropy Coding
• OSD — Onscreen Display
• PMMA — Polymethyl Methacrylate
• GRX — GPRS Roaming Exchange
• AMTFT — Active Matrix Thin Film Transistor

• BTP — Business Telecom Products, Inc.
• FOC — Fiber-Optic Cable
• ADIF — Accounting Data Interchange Format
• 100VG — 100 Voice Grade (IEEE 802.12 AnyLAN Standard)
• ULP — Upper Layer Protocol
• SINAD — SIgnal-to-(Noise And Distortion) ratio
• BHA — Busy Hour Attempts
• BP — Block Parity
• AEA — American Electronics Association's
• RS-422 — Recommended Standard 422 (ANSI/EIA standard for transmitting serial data)
• FRF-LMI — Frame Relay Forum - Local Management Interface
• ATCA — Advanced Telecom Computing Architecture
• UMTS — Universal Mobile Telecommunication System
• DCC — Digital Control Channel
• BUS — Broadcast and Unknown Server
• RDSS — Radio Determination Satellite Service
• TCS — Telephony Control Specification
• CCSA — Common Control Switching Arrangement
• UCM — Use Case Map
• GTM — Go to Meeting
• STD — Secondary Telecom District
• RM-ODP — Reference Model for Open Distributed Processing
• TOC — Telecommunication Operations Center
• BDFB — Battery Distribution Feeder Bay
• 3GSM — Third-generation Global System for Mobile (communications)
• FIRST — Forum of Incident Response and Security Teams (CERT)
• PSN — Public Switched Network
• ADTM — Asynchronous Data Transfer Mode
• VNL — Via Net Loss
• NTSC — National Television Standards Committee
• OIM — Operations Interface Module
• AGCH — Access Grant Channel
• AAL — ATM (Asynchronous Transmission Mode) Adaptive Layer
• SSU — Synchronization Supply Unit
• DTU — Date/Time Update
• CT — Cordless Telecommunications
• FR — Functional Requirement
• DMT — Discrete Multi-tone Transmission
• PT — Payload Type (ATM)
• NFR — Near-Field Recording
• TP — Termination Point
• CIS — Center for Integrated Systems
• KTS — Key Telephone System
• PTE — Path Terminating Equipment (SONET)
• PSQM — Perceptual Speech Quality Measure
• ETOM — Enhanced Telecom Operations Map
• VO — Voice Only
• RADSL — Rate Adaptive Digital Subscriber Line
• TP-PMD — Twisted Pair Physical Medium Dependent
• SAMI — Structured Adjustment & Maintenance Interface

• CDVT — Cell Delay Variation Tolerance
• HPN — Home Phone Network
• OODBMS — Object-Oriented Database Management Systems
• CDDI — Copper Distributed Data Interface
• LXT — Local Exchange Terminal
• BAN — Billing Account Number
• EC — Echo Cancelling
• ADM 3X — DS3 Add-Drop Multiplex
• BPP — Billed Party Preference
• ATD — Advanced Technology Demonstration
• ATRAC — Adaptive Transform Acoustic Coding
• CDA — Communications Decency Act of 1996
• SDN — Software Defined Network
• MCR — Minimum Cell Rate (ATM)
• SQL — Specified Quality Level
• 3GIP — Third Generation Internet Protocol
• NEMP — Nuclear Electromagnetic Pulse
• TSP — Telecommunications Service Priority
• IPXCP — Internetwork Packet Exchange Control Protocol
• TLP — Transmission Level Point
• JSC — Joint Scientific Committee (ICSU, WCRP, and WMO)
• DUV — Data-Under-Voice
• BORSCHT — Battery feed, Overvoltage protection, Ringing, Signaling, Coding, Hybrid, and Testing
• RNR — Receive Not Ready
• DDM — Data Distribution Manager
• BAM — Basic Access Module
• SCC — Specialized Common Carrier
• DDSN — Digital Derived Services Network
• TSI — time-slot interchange
• RLS — Recursive Least Squares
• PTM — Packet Transport Mode
• BASIZE — Buffer Allocation Size
• AI — Adapter Interface
• AMTI — Airborne Moving Target Indicator
• BAOC — Barring of All Outgoing Calls supplementary service
• EC-N — Electrical Carrier (n=a number, e.g., EC-4)
• MEH — Mobile-Executed Handoff
• HU — Hook Up
• EVC — Electronic Voucher Charging
• CM — Connection Manager
• AAP — Alternate Access Provider
• AIU — Analog Interface Unit
• PMT — Photo Multiplier Tube
• DSCS — Defense Satellite Communication System
• AAL2 — ATM (Asynchronous Transmission Mode) Adaptation Layer 2
• WFT — Wireline Formation Test
• LMDS — Local Multipoint Distribution Service
• BCSM — Basic Call State Model
• EC — Enhanced Cellular
• AQP — Association for Quality and Participation

• USF — Universal Server Farm
• ESG — Enhanced Service Gateway
• Z — Zulu Time
• MILNET — Military Network
• GFC — Generic Flow Control (ATM)
• RLA — Received Level Average
• USRT — Universal Synchronous Receiver/Transmitter
• BNCC — Base Network Control Center
• GOMP — Get Off My Phone
• CATI — Computer-Assisted Telephone Interviewing
• CLOS — Clear Line Of Sight
• MIS — Marketing Intelligence System
• CNID — Calling Number Identification Display
• TTC — Telemetry Telecommand and Control
• AMOLED — Active Matrix Organic Light-Emitting Diode
• BSS — Broadband Switching System
• PFE — Power Feed Equipment
• IPOATM — Internet Protocol over ATM
• RSN — Regional Service Network
• IXC — interexchange carrier
• STA — Science and Technology Agency (Japan)
• GOSIP — Government Open Systems Interconnection Profile
• CACM — Communications of the ACM
• MOS — Metal Oxide Semiconductor (FET Devices)
• MB — Measured Business
• ESA — Enhanced Subscriber Authentication
• DLE — Digital Local Exchange
• BSRF — Basic System Reference Frequency
• AAV — Alternate Access Vendor
• DTR — Down-Time Ratio
• ESM — electronic support measure
• AFI — Authority and Format Identifier
• VLR — Visitor Location Register
• IMPI — IP (Internet Protocol) Multimedia Private Identity
• IVN — Interactive Video Network
• LOB — Line Of Bearing/Balance
• AECT — Association for Educational Communications and Technology's
• QOTS — Quality Of Telephone Services
• SGSN — Serving GPRS (General Packet Radio Service) Support Node
• E2E — End-to-End
• DE — Discard Eligible
• CSCW — Computer-Supported Cooperative Work
• SAPI — Service Access Point Identifier
• CSP — Converged Service Platform
• VCA — Voice Connecting Arrangement
• WNAP — Wireless Network Access Point
• LDI — Long Distance Interconnect
• SLIP — Serial Line Internet Protocol
• VCC — Voice Call Continuity
• TD-CDMA — Time Division - Code Division Multiple Access

• AB — Answer Back
• CLF — Carrier Line Failure
• CD — Committee Draft
• CAN — Controller Area Network
• LSI — Large-Scale Integration
• CEE — Communaut? Economique Europ?enne
• DSU — Digital Service Unit
• SDHLR — Super-Distributed Home Location Register
• SMT — station management (protocol)
• UTRAN — UMTS (Universal Mobile Telecommunication System) Terrestrial Radio Access Network
• VCR — Videocassette Recorder
• DPT — Dial Pulse Terminate
• MVDS — Microwave Video Distribution System
• HDB3 — High-Density Bipolar Three-bit substitution
• GSM — Global System for Mobile telecommunications
• IMTS — Improved Mobile Telephone Service
• NCOS — Network Class Of Service
• ISD — International Subscriber Dialling
• GLT — Great Lakes Telecom
• DF — Direction Finding or Finder
• FD — Full Duplex
• BCS — British Computer Society
• DLT — Digital Line Termination
• LVM — Line Verification Module
• CCCI — Command, Control, Communications and Intelligence
• VAD — Voice Activity Detection
• DCEF — Distributed Cisco Express Forwarding
• LULT — Line Unit/Line Termination
• CDSL — Consumer Digital Subscriber Line
• INWATS — INward Wide Area Telecommunications Service
• SNI — Service Node Interface
• A/D — Analog-to-Digital converter
• SMU — Service Management Unit
• MERIS — medium-resolution imaging spectrometer
• QPA — Quality Performance Analysis
• PTT — Post Telegraph and Telecommunications
• ANSI — Advanced Network Signaling Input
• LFTYR — Ley Federal de Telecomunicaciones y Radiodifusión
• ANS — Advanced Network Services
• PTCL — Pakistan Telecommunication Company Ltd
• KSPS — KiloSymbols Per Second
• DS0 — Digital Signal Zero
• O — objective
• RTFM — Read The Friendly Manual
• VFL — Visual Fault Locator
• VCT — Variable Cam Timing
• SM OFC — Single-Mode Optical Fiber Cable
• SR — Service Request
• MBMS — Multimedia Broadcast/Multicast Service
• AEIMP — Apple Event Interprocess Messaging Protocol

• SDSL — Symmetrical Digital Subscriber Line
• BAP — Bandwidth Allocation Protocol
• ATU-R — ADSL (Asymmetric Digital Subscriber Line) Transceiver Unit - Remote terminal end
• AFRINIC — African Network Information Centre
• ECC — Emergency Communications Center
• LAT — Local Area Transport (network)
• BCIX — Berlin Commercial Internet Exchange
• DAF — Directory Access Function
• SR — Scanning Radiometer
• VAN — Value-Added Network
• MBS — Maximum Burst Size (ATM)
• LTU — Line Terminating Unit
• CCSS6 — Common Channel Signaling System # 6
• PROV — Provisioning
• WPBX — Wireless Private Branch Exchange
• SS7 — Signaling System 7
• TP — Transaction Processor
• ANT — ADSL Network Terminator
• DACS — Digital Access and Cross-Connect System
• PM — Processable Mode
• DOITT — Department of Information Technology and Telecommunications
• OCI — object code insertion
• RCT — remote Control Terminal
• RBS — Robbed Bit Signaling
• ISSI — Inter-Switching System Interface
• ALT — Automatic Link Transfer
• HSCSWD — High-Speed Circuit-SWitched Data
• ACMA — Atlantic Cable Maintenance Agreement
• UMTS — Universal Mobile Telecommunications Standard
• INAP — Intelligent Network Application Part
• HUP — Hook-UP
• COBE — Corporate Owned Business Only
• SGCP — Simple Gateway Control Protocol
• VGF — Voice Grade Facility
• EF&I — Engineering, Furnishing and Installation
• TRX — Tandem Repeater eXchange
• CCH — Common Channel Handler
• CPT — Cellular Paging Teleservice
• TWX — Teletypewriter Exchange (Telex)
• CS — Connection Segment
• CCR — Current Cell Rate (ATMF)
• NMS — NetWare Management System
• GOS — Gerry Otis Simpson
• JDC — Japan Digital Cellular
• LSMS — Local Service Management System
• PTI — Payload Type Indicator
• PLCP — Physical Layer Convergence Protocol (ATM)
• DMI — Desktop Management Interface (computing)
• TARP — Target Identifier Address Resolution Protocol
• FUD — Fair Use Doctrine

• BSC — Base Station Controller
• SCE — Service Creation Environment
• WBMP — Wireless Bitmap
• MO — Magneto-optic
• WAW — Wide Area Wireless
• AAS — Automatic Announcement Subsystem
• SVI — Service Interception
• TEM — Transmission Electron Microscope
• LZ — Lempel-Ziv compression algorithm
• XWI — XML (extensible markup language) for Wireless Images
• D3 — Digital channel bank, Third generation
• IOC — Interoffice Channel
• ATMS — automatic transmission measuring system
• MIN — Mobile Identification Number
• DTS — Digital Terminal Systems
• WIS — WAN (Wide Area Network) Interface Sublayer
• SBX — Small Business Exchange
• LTU — Line Termination Unit
• SYSADM — System Administrator
• COP — Character Oriented Protocol
• UIH — Unnumbered Information with Header check
• RYP — Russian Yellow Pages
• UDT — Unreliable Data Transfer
• NIMH — Nickel-Metal Hydride
• MNP — Mobile Number Portability
• PNM — Pulse Number Modulation
• FEBE — Far End Block Error (SONET)
• CDPD — Cellular Digital Packet Data
• SPT — System Page Table
• PMOS — P-channel Metal Oxide Semiconductor
• WRED — Weighted Random Early Detection
• RLC — Radio Link Control
• LCU — Lightweight Computer Unit
• CVT — Circuit Validation Test
• CU — Cooling Unit
• FLN — Fixed Line Network
• MDCP — Media Device Control Protocol
• CFR-47 — Code of Federal Regulations Title 47 (FCC)
• ARCNET — Attached Resource Computer Network
• CALA — Customer Address Location Area
• DEO — Digital End Office
• NICAD — Nickel Cadmium
• SIGTRAN — Signaling Transport
• STUN — Simple Traversal of UDP (User Datagram Protocol) through NAT (Network Address Translation)
• COI — Community of Interest
• DORA — EV-DO (EVolution-Data Optimized) standard Revision A
• PTN — Public Telephone Network
• WDSL — Wireless Digital Subscriber Line
• ROSE — Remote Operations Service Element
• TASI — Time Assigned Speech Interpolation

• BRAN — Broadband Radio Access Network
• VC — Virtual Circuit (ATM)
• BONDING — Bandwidth On Demand Interoperability Group
• DBF — Digital Beam-Forming
• MAC — Message Authenticity Check
• C² — Command and Control
• CMT — Commercial Metering Transponder
• AVT — Audio Visual Telecommunications
• SPI — Security Parameters Index
• NARC — Non-Automatic Relay Center
• DMB — Disconnect and Make Busy
• USPI — Universal Serial Phone Interface
• SHR — Self-Healing Ring
• DAS — Distributed Antenna System
• MTS — Message Transmission Subsystem
• QOD — Quality of Data
• ATIS — Automatic Transmitter Identification System
• AA — Auto-Answer
• CLI — Calling Line Identification
• XRF — X-Ray Fluorescence
• TPF — Transmission Priority Field
• FESS — Flywheel Energy Storage System
• PTM — Point-To-Multipoint
• AIS-V — Alarm Indication Signal - Virtual
• LCU — Line Control Unit
• LRF — Laser Range Finder
• MEECN — Minimum Essential Emergency Communication Network
• TACSIM — Tactical Simulation (Simulator)
• FPLMTS — Future Public Land Mobile Telecommunications System
• NSN — National Significant Number
• ISC — International Switching Center
• DCO — Dial Central Office
• TCL — Transverse Conversion Loss
• MP — Master Processor
• SS6 — Signalling System 6
• GOSIP — Government Open System Interconnection Profile
• E — Exchange
• CSL — component sublayer
• ATL — Advanced Technology Laboratory
• VTA — Vermont Telecommunications Authority
• ZBTSI — Zero Byte Time Slot Interchange
• CPN — Customer Premise Network
• CD ROM — Compact Disc Read-Only Memory
• SIO — Service Information Octet
• DPDCH — Dedicated Physical Data Channel
• SASL — Simple Authentication and Security Layer
• WATS — Wide Area Telecommunications Service
• MCPC — Multiple Channels Per Carrier
• CLASS — Cell Level ATM (Asynchronous Transfer Mode) Services Simulator
• LEC — Liquid Encapsulated Czochralski

• AAV — Alternative Access Vendor
• DS-1 — Digital Signal, Level 1
• TED — Triteal Enterprise Desktop
• A/C — Air Conditioner
• LRB — Loop Reverse Battery
• SMAS — Service Management System
• SCO — Synchronous Connection Oriented
• BPOP — Building Point of Presence
• PCIA — Personal Communications Industry Association
• WTL — Wireless Transport Layer
• CFS — Call for Service
• WDMW — Web Directory for Mobile and Wireless
• DCMES — Dublin Core Metadata Element Set
• ECDIS — Electronic Chart Display Information System
• TRCSL — Telecommunications Regulatory Commission of Sri Lanka
• PWM — Pulse width modulation
• WUP — Wired Up Privacy
• AH — Authentication Header
• TSR — Terabit Switch/Router
• TFL — Telecom Fiji Limited
• SSU — Stratospheric Sounding Unit (TOVS)
• HEC — Header Error Control
• AMP — amplifier / amplification
• CIPOA — Classical Internet Protocol over ATM (Asynchronous Transfer Mode)
• GEO — Geostationary Earth Orbit
• APR — Alarm Processing Remote
• RCF — Remote Call Forwarding
• IOS — Internet Over Satellite
• NAM — Number Assignment Module
• ACEK — Authentication Encryption Key
• CEPT — Conference of European Posts and Telecommunications
• ICLD — Inter-Channel Level Difference
• OID — Object Interaction Diagram
• CMAS — Cellular Management System
• AEE — Agent Execution Environment
• EMV — EuroPay, MasterCard, Visa
• DACS — Digital Access Carrier System
• EGPRS — Enhanced General Packet Radio Service
• TSGR — Transport System Generic Requirements
• CAE — Common Application Environment
• FWS — Fixed Wireless Services
• DOV — Data-Over-Voice
• CCC — CDMA Cluster Controller
• EADAS — Engineering and Administrative Data Acquisition System
• DLC — Digital Leased Circuit
• TON — IEEE/ACM Transactions On Networking
• AARQ — A-Associate Request
• ACNA — Access Customer Name Abbreviation
• RTU — Right to Use
• CYTA — Cyprus Telecommunications Authority

• ADTS — Ameritech Digital Transport Service
• BC — Basic Call
• MRCA — Most Recent Common Ancestor
• TAE — Terminal Adapter Equipment
• NSEP — National Security Emergency Preparedness
• JMA — Japanese Meteorological Agency
• ADM — Administration, Office of
• MAPDU — Management Application Protocol Data Unit
• JWG — Joint Working Groupof
• CTTC — Centre Tecnològic de Telecomunicacions de Catalunya
• APS — Advanced Power System
• OTF — On-The-Fly (data acquisition method)
• SLIC — Subscriber Loop Interface Circuit
• TRAC — Totally Reconfigurable Analog Circuit
• VGC — Voice Grade Channel
• SINS — Ship’s Inertial Navigation System
• CQ — Communications Quality
• CTIT — College of Telecommunications and Information Technology
• SMDS — Switched Multi-megabit Data Service
• XC — Cross-Connect
• CCITT — Comite Consultatif International Telegraphique et Telephonique (now ITU-T)
• HUMAN — High-speed Unlicensed Metropolitan Area Network
• WCMP — Wireless Control Message Protocol
• LQD — Line Quality Disturbance
• VHM — Voice Health Monitor
• OST — Office of Science and Technology
• DDS — Dataphone Digital Service (AT&T)
• VDSL — VHBR (Very High Bit Rate) Digital Subscriber Line
• FB — Fine Business
• LQR — Line Quality Report
• MNOS — Metal-nitride-oxide Semiconductor
• ASAS — All-Source Analysis System
• SMDR — station message detail recording
• MMS — Multimedia Message Service
• NMC — Nortel Matra Cellular
• DMNG — Digital Mobile News Gathering
• TACS — Total Access Cellular System
• DME — Distributed Management Environment (OSF)
• ADC — Advanced Data Control
• PNE — Path Number Efficiency
• AFIPS — American Federation of Information Processing Societies
• SMG — Super Master Group
• BHP — Burst Header Packet
• ACRE — Authorization and Call Routing Equipment
• INMS — Integrated Network Management System
• TPSP — Third Party Service Provider
• ITA — Illinois Telecommunications Association
• TDRS — Tracking and Data Relay Satellites
• CELP — Code Excited Linear Prediction
• SES — Scientific and Engineering Software

• FEBE-F — Far End Block Error count - Fast data
• MQFP — Metric Quad Flat Pack
• WAAS — Wide Area Augmentation System
• CSAA — Central Service Area Authority
• WPKI — Wireless Public Key Infrastructure
• CM — Common Mode
• ACL — Asynchronous Connection-less Link
• LPDP — Local Policy Decision Point
• ACA — Automatic Circuit Assurance
• BSVCI — Broadcast Signaling Virtual Channel Identifier
• CLIP — Caller Line Identification Presentation
• FOE — Fiber Optic Equipment
• SDCCH — Standalone Dedicated Control Channel
• EDD — Earliest Due Date
• LMS — Local Measured Service
• IPC — Initial Paging Channel
• EKTS — Electronic Key Telephone Set
• QEDI — Quod Erat Demonstrandum
• NSDI — National Spatial Data Infrastructure
• PAGCH — Paging and Access Grant Channel
• MITS — Metaphors for Integrated Telecommunications Services
• DSP — Data Service Provider
• MMC — Minimum Monthly Charge
• EDGE — Enhanced Data for GSM (Global System for Mobile communication) Evolution
• SEM — Sionscanning Electron Microscopy
• BTL — Bell Telephone Laboratories, Inc.
• SOR — Statement of Requirements
• DCS — Digital Cross-connect Switch
• NMC — Network Model Coverage
• DRTT — Dial Repeating Tie Trunk
• TRANS — Transaction
• CFNA — Call Forwarding No Answer
• LSAP — Link Layer Service Access Point
• ISP — International Signaling Point
• AIS-P — Alarm Indication Signal - Path
• 4G — Fourth Generation
• RBT — Ring Back Tone
• DFT — Draft Tax Forms
• HTO — Hellenic Telecommunications Organisation
• CNE — Certified Novell Engineer
• CSP — Continuous Speech Processing
• DFRI — Datacom Reference Frame Input
• ELEC — Enterprise Local Exchange Carrier
• ECA — Extended Calling Area
• RANAP — Radio Access Network Application Part
• TSD — Type Specific Driver
• DBN — Dial-Back Number
• ATACS — Army Tactical Communications System
• ALC — Automatic Line Controller
• FOTS — Fiber Optical Transmission System

• RAI — remote alarm indication
• SNI — Subscriber Network Interface
• GTXC — Global Telephone Exchange Carrier
• PRM — Performance Report Message
• EDT — European Deaf Telephone
• SRS — Supported Residential Services
• TSC — Technical Standards Committee
• SACS — Security Access Control System
• FEBE-I — Far End Block Error count - Interleaved data
• DCB — Digital Channel Bank (Sprint)
• FDMMA — Frequency Division Multiplexing Multiple Access
• MSG — Management Steering Group
• LAC — Line Assignment Center
• CSLIP — Compressed SLIP
• DISA — Direct Inward Switch Access
• ESP — Essential Service Protection
• UDC — Universal Digital Channel
• ETB — Empresa de Telecomunicaciones de Bogotá
• BTO — Betts Telecom Oklahoma
• DTW — Dynamic Time Warping
• APPN — Advanced Peer-to-Peer Network
• TOMS — Telecom Operations Management System
• CUG — Closed Users Group
• DACS — Digital Access Cross-Connect Switch
• RSL — Request and Status Links
• BIOS — Basic Input-Output System
• SC — Switching Center
• IRLAP — InfraRed Link Access Protocol
• CAL — Customer Access Line
• ATIS — Alliance for Telecommunications Industry Solutions
• ASP — Active Signaling Protocol
• DCSS — Digital Cross-connect Systems
• V — Vector
• AS — Active Service
• WAWS — Washington Area Wideband System
• TCAM — Telecommunications Access Method
• SAM — Service Access Multiplexer
• WLNP — Wireless Local Number Portability
• VLP — Very Low Power
• D/I — Drop and Insert
• WDF — Wireless Data Forum
• ADTS — Automated Digital Terminal System
• DR — Design Review
• WPOP — Wireless Point-of-Presence
• WAR — Wireless Access Revolution
• HCV — High Capacity Voice
• TWL — Leased Teletypewriter Service
• HQGSM — High-Quality Global System for Mobile communications
• VPL — Virtual Path Link (ATM)
• BANC — Broadband Access Network Coordination

• ITU-T — International Telecommunication Union - Telecommunications section
• IR — Information Request
• SSTC — Subsystem Status Test Control
• DDSD — Delay Dial Start Dial
• SMLC — Serving Mobile Location Center
• SHD — Smart Handheld Device
• SH — Shell
• AL — Alignment
• RCR — Research and Development Center for Radio Systems
• BFS — Broadcast File System
• DTV — Digital Television
• DORK — Disciples Of The Righteous King
• ASIC — Application Specific Instruction Code
• RDI-L — Remote Defect Indicator - Loop
• FECC-F — Forward Error Correction Count - Fast data