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Computing & IT >> Telecom Abbreviations

Look through 4999 acronyms and abbreviations related to Telecom:

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

• PPM — parts per million
• RAEX — Roaming Agreement EXchange
• S X S — Step-by-Step
• MAN — Metropolitan Area Network
• C4I — Command, Control, Communications, Computers, & Intelligence
• BPM — Beats Per Minute
• ISO — In Search Of
• CSMA/CD — Carrier sense multiple access / collision detection
• XA-FR — Exchange Access Frame Relay
• S-BCCH — Short Message Service Broadcast Control Channel
• TEMIP — Telecommunications Management Information Platform
• CONG — Congestion message
• IRC — Internet Relay Chat
• FDIC — Federal Deposit Insurance Corporation
• EPA — Environmental Protection Agency (US)
• SD — Standard Deviation
• C-NBAP — Common Node B Application Part
• CPU — Central Processing Unit
• CSMA — Carrier Sense Multiple Access
• X-OFF — Transmitter Off
• P&L — Profit and Loss statement
• RTN — Regional Telecommunication Network
• UAX 14 — Unit Automatic eXchange type 14
• X-ON — Transmitter On
• E-LEAD — Ear Lead
• B-ICI — Broadband Inter-Carrier Interface
• COB — close of business (End of duty day)
• ZDBOP — Ziff-Davis Benchmark Operation
• CPE — Customer Premises Equipment
• PDF — Portable Document Format (created by Adobe Acrobat)
• A-KEY — Authentication key
• WACN ID — Wide Area Communications Network IDentifier
• FIFO — First In, First Out
• NMSE — Normalized Mean Square Error
• UR — Your
• OC-256 — Optical Carrier Signal, Level 256
• LRU — Line Replaceable Unit
• FEMA — Federal Emergency Management Agency
• MLS — Microwave Landing System
• LLC — Limited Liability Company
• I.LINK — IEEE 1394, High Performance Serial Bus, implementation
• PDR — Preliminary Design Review
• OC-18 — Optical Carrier Signal, Level 18
• CU — See You
• CR — Carriage Return
• D-NBAP — Dedicated Node B Application Part
• RFP — Request For Proposal
• IP — Internet Protocol
• T-IC — T-interConnect
• SABGW — System Architecture Evolution Gateway

• QC — Quality Control
• ASTM — American Society for Testing and Materials (Philadelphia, Pennsylvania)
• M-CSI — Mobility management CAMEL (Customized Applications for Mobile network Enhanced Logic) Subscription Information
• CDR — Critical Design Review
• PDT — Pacific Daylight Time
• ISO — International Organization for Standardization
• F2F — Face To Face (also Meeting In Person)
• VIP — Very Important Person
• RFQ — Request For Quotation
• H323 — ANSI standard for format over IP
• PO — Purchase Order
• DAHDI — Digium/Asterisk Hardware Device Interface
• OC-9 — Optical Carrier Signal, Level 9
• AUP — Acceptable Use Policy
• ECU — Electronic Control Unit
• DAM — Diagnostic Acceptability Measure
• ATTN — Attention
• EAP — Employee Assistance Program
• T-CARRIER — Trunk Carrier
• VC-ATOD — Virtual Clearinghouse on Alcohol, Tobacco and Other Drugs
• CY — Calendar Year
• IRR — Internal Rate of Return
• WTG — Way To Go
• CEO — Chief Executive Officer
• EDI — Electronic Data Interchange
• KBYTE — Kilobyte (103)
• ACH — Automated Clearing House
• ISP — Internet Service Provider
• GSM — Global System for Mobile Communications
• C³CM — Command, Control and Communications Countermeasures
• RF — Radio Frequency
• IPO — Initial Public Offering
• CV — Curriculum Vitae
• QFSK — Quadrature Frequency Shift Keying
• VAZO — Violating All-Zero Octet
• CCB — Change Control Board
• LCD — Liquid Crystal Display
• AC — Alternating Current
• GUI — Graphical User Interface (goo-ey)
• ADM — Add-Drop Multiplexer
• ATM — Asynchronous Transfer Mode
• BRB — Be right back
• FET — Field Effect Transistor
• D-H — Diffie-Hellman
• TQM — Total Quality Management
• WB — Welcome Back
• WBS — Work Breakdown Structure
• AFAIK — As Far As I Know
• EST — Eastern Standard Time
• AMD — Advanced Micro Devices, Inc. (producer of computer chips)

• MOU — Memorandum of Understanding (an MOU between Food & Drug Administratin and a regulatory agency in another country allows mutual recognition of inspections)
• BTU — British Thermal Unit
• API — Application Programming Interface
• ADSL — Asymmetric Digital Subscriber Line
• WWW — World Wide Web
• DSC — Differential Scanning Calorimetry
• VAT — Value Added Tax
• DBORS — Data Base of Records
• PUHU — Pick Up Hang Up
• ASCII — American National Standard Code for Information Interchange
• R&D — Research & Development
• MTBF — Mean Time Before Failure
• SMTP — Simple Mail Transfer Protocol
• RDY — Ready
• SME — Subject Matter Expert
• ABC — activity based costing
• AOL — America on line
• SLA — Service Level Agreement
• DWDM — Dense Wavelength-Division Multiplexing
• CUG — Closed User Group
• GIS — Geographic Information System
• DOA — dead on arrival
• RQMT — Requirement
• WML — Wireless Markup Language
• IRL — In Real Life
• AIR — Account Information and Refill
• CSA — Canadian Space Agency
• MOB — Mobile
• ICT — Information and Communication Technology
• SRAM — Static Random Access Memory (ess-ram)
• COR — Carrier Operated Relay
• ABI — Application Binary Interface
• EDS — Electronic Data Systems Corporation
• PVT — Private
• PDA — Personal Digital Assistant
• O&M — Operation and Maintenance
• FAQ — Frequently Asked Questions (sometimes Pronounced Fak)
• ASA — American Standards Association
• ASME — American Society of Mechanical Engineers
• NPV — Net Present Value {economics}
• RPI — Retail Price Index
• SAR — Search And Rescue
• HTTP — Hypertext Transfer Protocol
• ESA — European Space Agency
• EIS — Executive Information System
• MRI — Magnetic Resonance Imaging
• EOM — End Of Message
• NYSE — New York Stock Exchange
• CD — Compact Disc
• RPM — Revolutions Per Minute, (Rotations Per Minute)

• TNYWR — The Number You Will Receive
• GPS — Global Positioning System (ex-NAVSTAR)
• VPN — Virtual Private Network (ATM)
• ATA — Area Transportation Authority
• DAC — Discretionary Access Control
• GATT — General Agreement on Tariffs and Trade (government)
• EU — European Union (1994; formerly referred to as the EEC or EC)
• MIS — Management Information System (OSHA)
• ACE — Access Control Entry
• BVR — Beyond Visual Range
• AM — Ante Meridian
• JV — Joint Venture
• ARPA — Advanced Research Projects Agency (made early internet)
• UDP — User Datagram Protocol (FDDI related)
• RFI — Request For Information. Sales department shorthand. Special priority when use in conjunction with RFN (see below).
• PCB — printed circuit board
• IVR — Interactive Voice Response (telephone technology)
• 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.
• CGI — Common Gateway Interface
• CAE — Computer-Aided Engineering
• CRT — Cathode Ray Tube (type of TV)
• CIO — Chief Information Officer
• NPI — New Product Introduction
• 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
• SAN — Storage Area Network
• CPM — Critical Path Method
• MDF — Main Distribution Frame
• DOD — United States Department of Defense
• TBD — To Be Determined
• RFC — Request For Comment
• DBMS — Database Management System
• CB — Call Back
• RAM — random-access memory
• EVP — Executive Vice President
• QMS — Quality Management System
• FAA — Federal Aviation Administration
• ACK — Acknowledge (telecommunications; Cf. NAK)
• MST — Mountain Standard Time
• NFS — Network File System
• DFD — Displaced Frame Difference
• COO — Chief Operation Officer
• ATCRBS — Air Traffic Control Radar Beacon System
• FX — Foreign Exchange
• NSF — National Sanitation Foundation
• DSS — Decision Support System
• SDR — Special Drawing Rights
• JIT — Just in time
• RDBMS — Relational Database Management System
• AM — Amplitude Modulation
• DES — Data Encryption Standard

• VVX — Voice and Video eXchange
• TTYL — Talk To You Later (Internet Slang)
• SOW — Statement Of Work
• ACK — ACKnowledgment
• SWAG — Scientific Wild Ass Guess
• AE — Account Executive
• IETF — Internet Engineering Task Force
• WWW3 — World Wide Web Consortium
• MBR — Master Boot Record
• ACC — Adaptive Cruise Control
• PGP — Pretty Good Privacy (encryption)
• CIS — Commonwealth of Independent States
• FIPS — Federal Information Processing Standard
• EEC — European Economic Community (predecessor of the European Union|EU)
• AES — Advanced Encryption Standard
• AIS — Automated Information System
• VM — Voice Mail
• SDMA — Space Division Multiple Access
• EC — European Commission
• PDH — Plesiochronous Digital Hierarchy
• CIR — Committed Information Rate (Frame Relay)
• CCSDS — Consultative/Consultative Committee for Space Data Systems
• DARPA — Defense Advanced Research Projects Agency (US)
• WDM — Wavelength Division Multiplexing (fiber optics)
• CPT — Carriage Paid To
• CAD — Computer Aided Designer
• ADD — Addendum
• NOS — Network Operating System
• DRAM — Dynamic Random Access Memory (dee-ram) (computing)
• CCM — counter-countermeasure
• MTTR — Mean Time To Repair
• QOS — Quality of Service
• ACM — Association for Computing Machinery
• CBT — Computer Based Training
• CRM — Customer Relationship Management
• Q&A — Question & Answer
• PDN — Public Data Network
• SLIP — Serial Line Interface Protocol
• PSK — phase-shift keying
• MB — Megabyte
• LRJ — Location Reject
• RM — Regional Manager
• NATO — North Atlantic Treaty Organisation
• SQA — Software Quality Assurance
• WWW — World Weather Watch
• WAN — Wide Area Network
• SDD — Software Design Document
• AOA — Angle Of Arrival
• DB — Decibel
• DNS — Domain Name System

• QA — Center for Quality Assurance in International Education
• AGC — Automatic Gain Control
• WEP — Wired Equivalent Privacy
• GPRS — General Packet Radio Service
• DHCP — Dynamic Host Configuration Protocol
• SCC — Standards Council of Canada
• POP — Point Of Presence (Internet)
• DSCP — Differentiated Services Control Point
• OCR — Optical Character Recognition
• APT — Automatic Picture Transmission
• TNX — Thanks
• BIP — Bit-Interleaved Parity
• ACE — Advanced Computing Environment
• CDT — Central Daylight Time
• GSA — U.S. General Services Administration
• DDD — Direct Distance Dial
• BUR — Bandwidth Usage Redundancy
• ADR — Address
• ROI — Return on Investment
• FM — frequency modulation
• NIH — Not Invented Here
• ATC — Air traffic control
• PNG — Portable Network Graphics (graphic file standard/extension)
• HVAC — Heating, Ventilation, and Air Conditioning
• BSD — Berkeley Software Distribution
• AATSR — Advanced Along-Track Scanning Radiometer
• CC — Carbon Copy
• MSN — Microsoft Network
• ISDN — Integrated Services Digital Network
• UPS — Ultraviolet Photoelectron Spectroscopy
• RFO — Reason For Outage
• BCC — Blind Carbon Copy
• SAS — Statistical Analysis System
• IRS — U.S. Internal Revenue Service
• TCO — Total Cost of Ownership
• BR — Branch
• ENIAC — Electronic Numerical Integrator And Computer
• SIC — Standard Industrial Classification (Code)
• SCSI — Small Computer System Interface
• DOJ — Department of Justice (US)
• ABET — Accreditation Board for Engineering and Technology, Inc.
• UAV — Unmanned Aerial Vehicle
• CS — Computer Science
• ACL — Access Control List
• MMS — Multimedia Messaging Service
• DSL — Digital Subscriber Line
• PRI — Primary Rate Interface (ISDN)
• CST — Central Standard Time (UTC-6 Hours)
• TNSTAAFL — There's No Such Thing As A Free Lunch
• EBCDIC — Extended Binary Coded Decimal Interchange Code (pronounced Eb-see-dik) (cf. BCD)

• ALC — Automatic Level Control
• PM — Preventive Maintenance
• CFO — Communication Filing Officer
• CAM — computer aided manufacturing
• AME — Amplitude Modulation Equivalent
• FFT — Fast Fourier Transform
• AAC — Advanced Audio Coding
• RWR — Radar Warning Receiver
• ECO — Engineering Change Order
• NEC — National Electrical Code
• NIC — Network Interface Card
• PC — Personal computer (host)
• BPS — bits per second
• SBU — Strategic Business Units
• EDT — Eastern Daylight Time
• EFT — Electronic Funds Transfer
• DNS — Domain Name Service
• AQL — Acceptable Quality Level
• RAID — Redundant Array of Inexpensive Disks
• Y2K — Year 2000
• CTD — Cumulative Trauma Disorder
• DLL — Dynamic Link Library (computer file)
• BBS — Bulletin Board System
• 100BASE-T2 — 100 Megabits per Second, Baseband, Two-pair Category 3 UTP cables
• WYSIWYG — What You See Is What You Get (pronounced Wizzy-wig. See Entry For Derived Acronyms)
• ARP — Address Resolution Protocol (ATM)
• DMSP — Defense Meteorological Satellite Program (U.S.)
• ERT — Emergency Response Team
• DSA — Digital Signature Algorithm
• ADPE — Automatic Data Processing Equipment
• CMS — Content Management System
• DC — Direct Current
• UI — User Interface
• NIST — National Institute of Standards and Technology
• ROFL — Rolling on the floor laughing
• DDL — Data Definition Language
• VHF — Very High Frequency
• ERP — Enterprise Resource Planning
• FAR — Federal Aviation Regulation
• BST — British Summer Time
• ASP — Application Service Provider
• CMM — Capability Maturity Model
• PERT — Program Evaluation and Review Technique
• 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
• LED — law enforcement desk; light emitting diode
• ACD — Automatic Call Distributor
• ZIP — Zone Improvement Plan
• EDVAC — Electronic Discrete Variable Automatic Computer
• DDE — Dynamic Data Exchange (in software parlance)
• RDP — Radar Data Processing

• OBO — Or Best Offer
• JAXA — Japan Aerospace Exploration Agency
• CAA — Civil Aviation Authority
• ROS — Return on Sales
• BPR — Business Process Re-engineering
• STS — Space Transportation System
• UTC — Coordinated Universal Time
• ITU — International Telecommunication Union
• MRC — Monthly Recurring Charge
• ADM — Add/Drop Multiplexer
• SEI — Software Engineering Institute
• AAAI — American Association for Artificial Intelligence's
• IM — Instant Message
• OMG — Object Management Group
• AES — Auger Electron Spectroscopy
• DLR — Design Layout Record
• SQL — Structured Query Language
• VIRUS — Vital Information Resources Under Siege
• DME — Distance Measuring Equipment
• AD — Active Directory
• LEO — Low Earth Orbit (satellite communications)
• SOHO — Small Office Home Office
• EMG — Electromyogram
• MLS — Multiple Listing Service
• DTE — Data Terminal Equipment
• RNC — Radio Network Controller
• ISAKMP — Internet Security Association and Key Management Protocol
• ABR — Available Bit Rate
• AGP — Accelerated Graphics Port
• EFF — Electronic Frontier Foundation
• AT&T — American Telephone and Telegraph (U.S. company, also known as "Ma Bell")
• ATN — Aeronautical Telecommunication Network
• AAAS — American Association for the Advancement of Science
• ACO — Additional Call Offering
• ASR — Airport Surveillance Radar
• DQE — Detective Quantum Efficiency
• CDR — Call-Detail Record
• RACON — Radar Beacon
• CFE — Contractor-Furnished Equipment
• PMA — Physical Medium Attachment
• CU — Control Unit
• TC — Telephone Call
• EEG — Electro-EncephaloGram
• FCC — Federal Communications Commission (US)
• NMR — Nuclear Magnetic Resonance
• PM — post meridian
• B2B — Business to Businesse
• CMI — Computer Managed Instruction
• CLI — Command line Interface (Cabletron)
• SCM — Supply Chain Management

• RM — Resource Management
• EW — Electronic Warfare
• AADC — Automated Area Distribution Center
• DFS — Distributed File System
• CAUCE — Coalition Against Unsolicited Commercial Email
• AC — Access Control
• VTC — Video Teleconference
• COQ — Cost Of Quality
• HZ — cycles per second (hertz)
• TCP — Transmission Control Protocol
• SAIC — Science Applications International Corporation
• IP — Intellectual Property
• PECVD — Plasma-Enhanced Chemical Vapor Deposition
• UN — United Narions
• USD — United States Dollar
• RU — Are You?
• DQPSK — Differential Quadrature Phase-Shift Keying
• ASEAN — Association of South East Asian Nations
• ISBN — International Standard Book Number (ISO 2108)
• KISS — Keep It Simple Stupid
• BRI — Basic Rate Interface
• HSD — High Speed Data
• OSHA — Occupational Safety and Health Act (1970)
• BJT — Bipolar Junction Transistor
• DOS — Disk Operating System
• DCN — Design Change Notification
• SBC — Southwestern Bell Corporation
• USB — Universal Serial Bus
• NTIS — National Technical Information Service Technology Administration
• STP — standard temperature and pressure (0° and 1 atm)
• AVHRR — Advanced Very High Resolution Radiometer  
• DSTE — Digital Subscriber Terminal Equipment
• LMS — Learning management system
• CHAP — Challenge Handshake Authentication Protocol (ATM)
• CRL — Certificate Revocation List
• W3C — World Wide Web Consortium
• VR — Virtual Reality
• ATS — applications technology satellite
• WIPO — World Intellectual Property Organization
• ISSN — International Standard Serial Number (ISO 3297)
• DCOM — Distributed Component Object Model
• EOT — End Of Transmission
• ASK — amplitude shift keying
• NTIA — National Telecommunications and Information Administration
• HDML — Handheld Device Markup Language
• TCP/IP — transmission control protocol/internet protocol
• EAP — Extensible Authentication Protocol
• NEMA — National Electric Manufacturer's Association
• AWG — American Wire Gauge
• SPC — Statistical Process Control. Forerunning quality theory from the 1960s to TQC and TQM.

• OFC — Office
• PM — Project Manager
• SVP — Senior Vice President
• RPC — Remote Procedure Call
• EEPROM — Electrically Erasable Programmable Read-Only Memory
• DTX — Discontinuous Transmission
• CIA — Central Intelligence Agency
• PST — Pacific Standard Time (UTC-8 Hours)
• 9 — Nine
• UHF — Ultra High Frequency (300-3000 MHz; 1m-10cm)
• TV — Television
• AF — Audio Frequency
• ATM — Adobe Type Manager
• PPB — parts per billion (109)
• AT&T — American Telephone & Telegraph
• SMS — Short Message Service
• NOAA — National Oceanic and Atmospheric Administration (US)
• ITSEC — Information Technology Security Evaluation Criteria
• TCB — Trusted Computing Base
• ISRO — Indian Space Research Organisation
• CIM — Common Information Model
• IANA — Internet Assigned Numbers Authority
• CM — Configuration Management
• CORBA — Common Object Request Broker Architecture
• MHS — Message Handling System (electronic)
• JPEG — Joint Photographic Experts Group (24-bit image storage format)
• BT — British Telecommunications
• I/O — Input/Output
• AFC — Automatic Frequency Control
• NA — Not Applicable
• FDDI — Fiber Distributed Data Interface
• B3ZS — bipolar 3-zero substitution
• QI — Quality Improvement
• DTI — Department of Trade and Industry (UK)
• WMO — World Meteorological Organization (ICSU)
• ISS — International Space Station
• AEC — Architecture, Engineering, Construction
• PT — Project Team
• ADT — Atlantic Daylight Time (UTC-3 Hours)
• SIG — Special Interest Group
• VAC — Vacant
• PE — Polyethylene
• FCA — Free Carrier
• EPR — Ethylene-Propylene Rubber
• WTO — World Trade Organisation
• FTTB — Fiber To The Building
• SAE — Society of Automotive Engineers
• EDD — Envelope Delay Distortion
• T&C — Terms & Conditions
• CCIS — Common Channel Interoffice Signaling

• ICMP — Internet Control Message Protocol
• AE — Application Entity
• ASQC — American Society for Quality Control's
• CUL — See You Later
• Z — Zero
• MDA — Monochrome Display Adapter
• CRC — Contrôle de Redondance Cyclique (French: Cyclic Redundancy Check)
• SLF — Super Low Frequency
• PBX — Private Branch eXchange (company phone system)
• NSA — National Security Agency
• APIC — Advanced Programmable Interrupt Controller
• BSOD — Blue Screen Of Death
• BECN — Backward Explicit Congestion Notification
• SP — Service Provider
• FASB — Financial Accounting Standards Board
• EISA — Extended Industry Standard Architecture
• AP — Application Protocol
• PAR — Precision Approach Radar
• AMT — Amount
• ATF — Advanced Tactical Fighter
• BCD — Binary-Coded Decimal
• ACTV — Active
• RFD — Request For Discussion
• SHA — Secure Hash Algorithm
• MIME — Multipurpose Internet Mail Extension
• OSI — Open Systems Interconnection (iso Standard)
• RFI — Radio Frequency Interference
• PSTN — Public Switched Telephone Network
• SPC — Stored Program Control
• TOS — Type Of Service
• IMEI — International Mobile Equipment Identity
• LF — Low Frequency
• M — Meter
• RSVD — Reserved
• SSL — Secure Socket Layer
• SGML — Standard Generalized Markup Language
• BER — Bit-Error Rate
• CW — Continuous Wave
• ECR — Electronic Cash Register
• BBU — Baseband Unit
• RCU — Remote Control Unit
• EDP — Electronic Data Processing Plc (London Stock Exchange [LSE])
• BPRZ — Bipolar Return-to-Zero
• ECP — Engineering Change Proposals
• WAP — Wireless Application Protocol
• ARA — Apple Remote Access
• DMTS — Distinguished Member Of Technical Staff
• SNMP — Simple Network Management Protocol (ATM)
• MAC — Message Authentication Code
• APPL — Application

• PWD — Password
• BIS — Bureau of Indian Standards
• AVL — Available
• NMT — Nordic Mobile Telephone
• FCS — Frame check sequence (Ethernet)
• NAFTA — North American Free Trade Agreement
• PLD — Programmable Logic Device
• ICANN — Internet Corporation for Assigned Names and Numbers
• AMI — Advanced Metering Infrastructure
• CBC — cipher block chaining
• NIST — National Institute of Standards & Technology (US)
• KM — Knowledge Management
• LEC — Local Exchange Carrier
• ADT — Abstract Data Type
• JIS — Japanese Industrial Standard
• OS — Operating System
• QAM — quadrature amplitude modulation
• SML/SMS — Service Management Layer/Service Management Service
• PPP — Point-to-Point Protocol
• CIC — Circuit Identification Code
• ACPI — Advanced Configuration and Power Interface
• MF — Medium Frequency
• OSS — Operational Support System
• KHZ — kilohertz (1000 cycles per second)
• BNSC — British National Space Centre
• DMA — direct memory access (computer term)
• AT — Advanced Technology
• CRBT — Caller Ring Back Tone
• SXS — Step-By-Step
• LCP — Link Control Protocol
• MMU — Memory Management Unit
• EGA — Enhanced Graphics Adapter
• PDU — Protocol data unit (such as segment, packet, frame, etc.)
• ADN — Advanced Digital Network
• AXE 10 — Series of electronic telephone exchanges from L.M. Ericsson
• BS — Base Station
• RQMTS — Requirements
• NRC — National Research Council (Canada)
• D-RAM — Dynamic Random Access Memory
• ACFQ — Absence Compensation Fair Queuing
• LP — Low Pressure
• B2C — Business-to-Consumer
• CRIS — Carrier Route Information System
• ERP — Enterprise Resource Management
• ECE — Economische Commissie voor Europa (United Nations) (Dutch: Economic Commission for Europe)
• CFD — computational fluid dynamics
• CCSD — command communications service designator; control communications service designator
• GRE — Generic Routing Encapsulation
• ADF — Automatic Direction Finder
• RMS — root mean square (preferred over "RMS")

• NCSA — National Center for Supercomputing Applications
• RTU — Remote Terminal Unit
• TPDU — Transport Protocol Data Unit
• HSDPA — High-Speed Downlink Packet Access
• OM — Old Man
• YL — Young Lady
• HTTPS — HyperText Transfer Protocol Secure
• CGI — Computer-Generated Imagery
• CMP — Connection Management Protocol
• USGS — United States Geological Survey (DOI)
• SOGA — Share of Gross Adds
• ELF — Extremely Low Frequency
• TAC — Technical Assistance Center
• RFS — Request For Service
• ELINT — Electronic Intelligence Satellite
• CATV — Cable Television
• DSSS — Direct Sequence Spread Spectrum
• MS — Mobile Station
• URI — Uniform Resource Identifier
• NBS — National Bureau of Standards (US)
• PABX — private automatic branch exchange (telephone)
• MS — Millisecond
• CDMA — Code Division Multiple Access (voice/data transmission)
• HW — Hardware
• ASQ — Alpha System Qualification
• BUS — Business
• RACF — Resource Access Control Facility
• EMS — Express Mail Service
• DCE — Distributed Computing Environment
• RCC — Rescue Coordination Center
• MIPS — Millions of Instructions Per Second
• OSPF — Open Shortest Path First (ATM)
• JPL — Jet Propulsion Laboratory (California Institute of Technology) (NASA)
• C4 — Command, Control, Communications, and Computers
• UAS — Unavailable Seconds
• WB — Write Back
• FCW — Federal Computer Week
• EOB — End Of Business
• RIP — Routing Information Protocol
• DC — Disconnected
• DUP — Duplicate
• SIL — Speech Interference Level
• DSA — Directory System Agent
• DOM — Document Object Model
• IEC — International Electrotechnical Commission
• AS — Autonomous System
• DIT — Directory Information Tree
• CFA — Carrier Facility Assignment
• MOS — Model Output Statistics
• WLTF — Wireless LAN (Local Area Network) Task Force

• DLC — Digital Loop Carrier
• ISAS — Institute of Space and Astronautical Sciences (Japan)
• BYOD — Bring Your Own Device
• ISO — Infrared Space Observatory
• GB — Gigabyte
• ECMA — European Computer Manufacturer's Association
• VB — Visual Basic
• PVC — Permanent Virtual Circuit (ATM)
• SIT — Static Induction Transistor
• TTYL — Type To You Later
• EMC — Electromagnetic Compatibility
• CERT — Computer Emergency Response Team
• CES — Consumer Electronics Show
• CIS — CompuServe Information Service
• RSN — Real Soon Now [which may be a long time coming]
• ROTFL — Roll On The Floor Laughing
• IRS — Interface Requirements Specification
• JSC — Johnson Space Center (Houston, TX)
• ESF — Extended Super Frame (ATM)
• TLS — Transport Layer Security
• ME — Mobile Equipment
• LCN — Logical Channel Number
• HDLC — High-Level Data Link Control
• MIC — Message Integrity Check
• CSO — Customer Service Operations
• DSP — Digital Signal Processor
• MS — Message Store
• MAC — Media Access Control
• STM — Short Term Memory
• RAD — Rapid Application Development
• DNIS — Dialed Number Identification Service
• 3G — Third Generation mobile phone network
• SCADA — Supervisory Control And Data Aquisition
• WAFB — Wireless Absolute Fairness Bound
• NAS — Network Access Server
• YP — Yellow Pages
• SNR — Signal-to-Noise Ratio
• DASD — Direct Access Storage Device
• NESDIS — National Environmental Satellite, Data, and Information Service
• PET — positron emission tomography
• CG — Coast Guard
• PLMN — Public Land Mobile Network
• ADC — Analog-Digital Converter
• DT — DWDM (Dense Wavelength Division Multiplexing) Terminal
• CAM — Computer-Aided Mapping
• PIN — Personal Identification Number
• LD — Long Distance
• IW — Information Warfare
• TAG — Technical Advisory Group for Biological Control Agents of Weeds
• CMD — Command

• DMX — De-MultipleXer
• LPE — Liquid Phase Epitaxy
• DTR — Data Terminal Ready
• CHF — Swiss Franc
• CIM — Corporate Information Management
• ASI — Asynchronous Serial Interface
• APC — American Power Conversion
• ACT — ACTIVITY, ACTIVITIES
• PD — Public Domain
• PDS — Protected Distribution System
• LLC — Logical Link Control
• VOL — Volume
• RAN — Radio Access Network
• IMPACT — Integrated Manufacturing Precision Assembly Cellular Technology
• JST — Japan Standard Time
• VDS — Variable Depth Sonar
• ANI — Automatic Number Identification (Caller ID)
• HF — High Frequency
• STA — State
• AYT — Are You There
• AMI — Alternate Mark Inversion
• CA — Certificate Authority
• IRLAN — Infrared LAN
• RJ-14 — Registered Jack type 14 (2-wire connector)
• OMS — Optical Multiplex Section
• LQC — Line Quality Control
• RH — Relative Humidity
• PRF — Pulse Repetition Frequency
• TM — Technical Manual
• CDS — Cell Directory Service
• MVS — Multiple Virtual Storage
• HTML — Hyper Text Markup Language
• APS — Automatic Protection Switching (SONET/SDH)
• MS — Management System
• ARPU — Average Revenue Per User
• MGMT — Management
• PAN — Personal Area Network
• RSVP — Resource Reservation Protocol (Internet)
• SPA — Special Prorate Agreement
• SOAP — Simple Object Access Protocol
• DPC — Destination Point Code
• CATV — Community Antenna Television
• CG — Center of Gravity (DXS)
• CMC — Career Management Center
• LF — Line Feed
• ESTEC — European Space Research and Technology Centre
• VOIP — Voice Over IP (Internet Protocol)
• AT — Access Tandem
• LDAP — Lightweight Directory Access Protocol (pronounced Ell-dap)
• FC — Fibre Channel

• EAI — Enterprise Application Integration
• DOT — Department of Telecommunications (India)
• LLU — Local Loop Unbundling
• CAB — Conformity Assessment Body
• BIOS — Basic Input Output System
• IS — Intermediate System
• MPLS — Multi Protocol Label Switching
• VCC — Virtual Channel Connection (ATM)
• SDH — Synchronous Digital Hierarchy (ATM)
• FTTH — Fiber To The Home
• CEV — Controlled Environment Vault
• CIFS — Common Internet File System
• ITT — Invitation To Tender
• CLNP — ConnectionLess-mode Network Protocol
• IRDA — Infrared Data Association
• AIS — Alarm Indication Signal
• CO — Certificate of Origin
• OLE — Object Linking and Embedding (Microsoft communication protocol)
• ECN — Explicit Congestion Notification
• CS — Cable Select
• STI — Speech Transmission Index
• DCS — Digital Cross-connect System
• AR — Access Rate
• BGP — Border Gateway Protocol (routing protocol)
• SW — South West
• PCI — Peripheral Component Interconnect
• BPDU — Bridge Protocol Data Unit
• FCA — Free Carrier Absorption
• CBDS — Connectionless Broadband Data Service
• DRM — Digital Rights Management
• UPS — Uninterruptible Power Supply
• YAHOO — You Are Hazy Over Oranges
• OTN — Optical Transport Network
• BG — Background
• NIMBY — Not In My Back Yard
• SSM — Source-Specific Multicast
• BLOS — Beyond Line-Of-Sight
• WMAN — Wireless Metropolitan Area Network
• SEM — Space Environment Monitor
• NCS — National Communications System
• DID — direct inward dial
• 1000BASE-T — 1000 Megabits per Second, Baseband, Twisted Pair
• NIC — Network Information Center
• IS — International Standard
• TG — Task Group
• VLF — Very Low Frequency
• BRA — Basic Rate Access
• DIBL — Drain-induced Barrier Lowering
• CBEMA — Computer & Business Equipment Manufacturers Association
• PAL — Programmable Array Logic

• CAD — Computer-Aided Design
• ACR — Attenuation Crosstalk Ratio
• CABS — Carrier Access Billing System
• COO — Cost of Ownership
• BOFH — Bastard Operator From Hell
• AML — Amplitude Modulated Link
• MIB — Management Information Base (ATM)
• POTS — Plain Old Telephone Service (FCW)
• AU — Audio Unit
• MCSD — Microsoft Certified Solution Developer
• AMLCD — Active Matrix Liquid Crystal Display
• CRO — Central Records Office
• DCMI — Dublin Core Metadata Initiative (Online Computer Library Center)
• VXML — Voice eXtensible Markup Language
• DA — Destination Address
• MHS — Microwave Humidity Sounder
• VM — Virtual Machine
• DSN — Deep Space Network - network of large antennas and communication facilities.
• PCMCIA — Personal Computer Memory Card International Association
• MDA — Model Driven Architecture
• UML — Unified Modeling Language (Object Management Group, OMG)
• SVC — Scalable Video Coding
• WPAN — Wireless Personal Area Network
• IPX — Internetwork Packet Exchange
• DAP — Directory Access Protocol
• NOC — Network Operations Center
• NLMS — Normalized Least Mean Square
• MTSO — Mobile Telephone Switching Office
• RTS — Request To Send
• WG — Working Group
• ADP — Automatic Data Processor
• TB — Terabyte
• ISI — Inter-Symbol Interference
• OAM&P — Operations, Administration, Maintenance & Provisioning
• CAV — Constant Angular Velocity
• CC — Call Control
• BT — BlueTooth
• FAX — Facsimile
• VAS — Value Added Services
• ZIP — Zone Information Protocol
• IDT — Integrated Digital Terminal
• UAN — Universal Access Number
• 100BASE-T — 100 Megabits per second, Baseband, Twisted pair
• CCTA — Central Computer and Telecommunications Agency
• SKU — Stockkeeping Unit
• CFD — Call For Discussion
• DUC — Digital Up-Converter
• AMHS — Automated Message Handling System
• TS — Technical Specification
• MBPS — Megabits per second

• E — Energy
• VOD — Video On Demand
• ISA — Industry Standard Architecture
• EEA — European Economic Area
• HSS — Home Subscriber Server
• AFSK — Audio Frequency Shift Keying
• IIS — Internet Information Services
• AFS — Andrew File System
• MCD — Magnetic Circular Dichroism
• EPR — Electron Paramagnetic Resonance
• PPARC — Particle Physics and Astronomy Research Council
• BAN — Base Area Network
• SCTP — Stream Control Transmission Protocol
• PDN — Packet Data Network
• 2W — Two Wire
• COM — Component Object Model
• ESF — Edge Spread Function
• CFV — Call For Vote(s)
• NOTAM — Notice to Airmen
• DS — Digital Signal
• PAP — Password Authentication Protocol (ATM)
• WS — Workstation
• ASIC — application-specific integration circuit
• COMJAM — Communications Jamming
• MCU — Multipoint Control Unit
• CCNA — Cisco Certified Network Associated
• ASR — Automatic Speech Recognition
• FR — Frame Relay
• ADCCP — Advanced Data Communications Control Procedures
• AOI — Area Of Interest
• AEW — Airborne Early Warning
• VBR — Variable Bit Rate (ATM)
• VOC — Volatile Organic Compounds (air pollution)
• FSAI — Fiber Serving Area Interface
• MME — Mobility Management Entity
• CF — Compact Flash
• NIS — Network Information Service
• ATSR — Along-Track Scanning Radiometer
• RDF — Radio Direction Finder
• OAS — Organization of American States
• RCV — Receive
• NTFS — New Technology File System
• TE — Traffic Engineering
• 911 — Emergency Services Phone Number
• LSR — Local Service Request
• NLM — National Library of Medicine (National Institutes of Health)
• WORM — Write-Once, Read-Many
• RJ-25 — Registered Jack type 25 (6-wire connector)
• DIS — Distributed Interactive Simulation
• EPABX — Electronic Private Automatic Branch Exchange

• ADL — Advanced Distributed Learning
• LPC — Linear Predictive Coding
• ECT — Explicit Call Transfer
• EMR — Electromagnetic Radiation
• MSU — Microwave Sounding Unit
• RSRQ — Reference Signal Received Quality
• UA — User Agent
• MPI — Message Passing Interface
• JVM — Java Virtual Machine
• GOS — Grade Of Service
• COMINT — Communications Intelligence
• FUP — Fair Use Policy
• TEC — Total Electron Content
• VLL — Virtual Leased Line
• SVD — Singular Value Decomposition
• ARIN — American Registry for Internet Numbers
• TEL — Telephone
• DCP — Design Change Package
• ASTD — American Society of Training and Development (Alexandria, Virginia)
• SA — Scientific American
• TOP — Technical Office Protocol
• ES — Errored Second
• EC — European Community
• IN — Intelligent Network
• ARINC — Aeronautical Radio Incorporated
• GDS — Global Distribution System
• SPI — Service Provider Interface
• CICS — Customer Information Control System (IBM Mainframe Software; Kicks Or C-I-C-S)
• IMSI — International Mobile Subscriber Identity
• ASR — Access Service Request
• F — Fellow
• STP — Spanning Tree Protocol
• EAC — Engineering Accreditation Commission
• CAN — Campus Area Network
• RT — Radiotelephone
• GDM — GSM (Global System for Mobile communications) Data Module
• LZ — Landing Zone
• CAC — Carrier Access Code
• CBP — Coded Block Pattern
• MTU — Maximum Transmission Unit
• PCM — Pulse-Code Modulation
• APM — Advanced Power Management
• E — Echo Time Zone
• CTS — Clear To Send
• FCP — Fibre Channel Protocol
• WLAN — Wireless Local Area Network
• VOP — Voice Over Packet
• MC — Message Center
• YYP — Yahoo Yellow Pages
• 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)

• CCD — Charge Coupled Device - a device for the movement of electrical charge.
• AFP — AppleTalk Filing Protocol
• SM — Senior Member
• WPM — speech--words per minute
• FA — Functional Area
• TBD — To Be Decided
• TCSEC — Trusted Computer System Evaluation Criteria
• HDSL — High-bit-rate Digital Subscriber Line
• SAR — Specific Absorption Rate
• CGM — Computer Graphics Metafile
• FAT — File Allocation Table
• FXO — Foreign Exchange Office
• BOC — Bell Operating Company
• RARP — Reverse Address Resolution Protocol
• IMC — Intermediate Metal Conduit
• MD — Mediation Device
• MSE — Mobile Subscriber Equipment
• NI — Network Interface
• CSPRM — Common Signaling Protocols Resource Module
• PKI — Public Key Infrastructure (cryptography)
• SLP — Service Location Protocol
• DDS — Digital Data Service
• PGA — Programmable Gate Array
• UL — Uplink
• OTS — Optical Transmission Section
• DDCMP — Digital Data Communications Message Protocol
• ARG — Argument
• PSD — Phase-Sensitive Detector
• TIA — Telecommunications Industry Association
• ADEOS — ADvanced Earth Observing Satellite (Japan)
• RRN — Routing Recording Number
• 100BASE-T4 — 100 Megabits per Second, Baseband, Four-pair Category 3 UTP cables
• COAX — Coaxial
• ESS — Electronic Switching System
• BS — Beam Splitter
• SATAN — Security Administrator Tool for Analyzing Networks
• MIS — Management Information Service
• TWT — Traveling Wave Tube
• CT — Computer Telephony
• SHF — Super High Frequency
• HEHO — Head End Hop Off
• TO — Technical Order
• STP — Signal Transfer Point
• ECPA — Electronic Communications Privacy Act 1986
• BERT — Bit Error Rate Tester (telecommunication)
• BACP — Bandwidth Allocation Control Protocol
• CMT — Cadmium Mercury Telluride
• ADF — automatic document feeder
• MP — Multilink Protocol
• AIFF — Audio Interchange File Format

• DMARC — Demarcation point
• STK — Satellite Tool Kit
• SDK — Software Development Kit (Microsoft)
• ECAC — European Civil Aviation Conference
• OSTP — Office of Science and Technology Policy
• CPS — Cycles Per Second (now Hertz)
• NSAI — National Standards Authority of Ireland
• EAS — Extended Area Service
• ARQ — Automatic Repeat-reQuest
• RCS — Radar Cross Section
• TOS — Temporarily Out of Service
• ITP — Interactive Telecommunications Program
• AAS — Adaptive Antenna System
• IP — Intelligent Peripheral
• SCP — Service Control Point
• NMS — Network Management System
• P — Predicted
• NFPA — National Fire Protection Association
• MSR — Microwave Scanning Radiometer
• TLC — The Learning Channel
• LEN — Line Equipment Number
• SDM — Service Delivery Management
• IV — Initialization Vector
• DX — Duplex
• EHF — Extremely High Frequency
• OLAP — Online Analytical Processing
• E&M — ear and mouth (special signaling leads)
• NOAO — National Optical Astronomy Observatories (Tucson, AZ)
• MPEG — Motion Picture Experts Group
• EMS — Enhanced Messaging Service
• SPADATS — Space Detection And Tracking System
• CD — Critical Dimension
• TI — Time Interval
• M — Management
• NNTP — Network News Transfer Protocol
• FSK — Frequency-Shift Keying
• AAV — Accountholder Authentication Value
• RP — Reference Point
• PUB — Publication (file name extension)
• QPSK — aeronautical quadrature phase shift keying
• WWAN — Wireless Wide Area Network
• ROSAT — Roentgen Satellite
• DDN — U.S. Defense Data Network
• MMSI — Maritime Mobile Service Identity
• BCH — Binary Coded Hexadecimal
• TN — Telephone Number
• BSA — Business Software Alliance
• ECM — Electronic Counter Measures
• SEC — Software Engineering Center
• MCA — Micro Channel Architecture

• LEP — Large Electron Positron
• SDLC — Synchronous Data Link Control
• CDA — Command and Data Acquisition
• DBS — Direct Broadcast Satellite
• B-ISDN — Broadband Integrated Services Digital Network
• AFM — Atomic Force Microscopy
• TRM — Technical Reference Model
• LQR — Linear Quadratic Regulator
• STN — Station Casinos, Inc.
• OC — Optical Carrier
• CO — Central Office
• FITS — Flexible Image Transport System
• TKIP — Temporal Key Integrity Protocol
• CSAT — Customer Satisfaction
• TELECOMMUTE — Telecommuting
• KB — Kilobyte: One thousand and twenty-four bytes kbps kilo bit per second
• SBC — Session Border Controller
• ISMI — International mobile subscriber identity
• LNP — Local Number Portability
• RA — Risk Analysis
• DVP — Digital Voice Privacy
• SML — Service Management Layer
• AUD — Audit
• BER — Basic Encoding Rules (ASN.1)
• Y — Yttrium
• ELT — Emergency Locator Transmitter
• OD — Outside Diameter
• KDC — Kerberos Key Distribution Center
• FR PVC — Frame Relay Permanent Virtual Connection
• OPC — Originating Point Code
• 4W — Four-Wire
• FE — Far End
• TCR — Temperature Coefficient of Resistance
• MIT — Massachusetts Institute of Technology (U.S.)
• GHZ — Gigahertz
• PTA — Pakistan Telecommunication Authority
• EGP — Exterior Gateway Protocol
• ARC — Army Reuse Center
• BIP — Band Interleaved by Pixel
• PUK — PIN (Personal Identification Number) Unlocking Key
• ARPANET — ARPA Network
• ISO — Independent System Operator (US) (see also TSO) Responsible for grid management, but does not own assets. (electricity)
• RSS — Really Simple Syndication
• ATS — Automatic Transfer Switch
• SVC — Switched Virtual Connection
• PDC — Personal Digital Cellular
• CU — Channel Unit
• DSLAM — Digital Subscriber Line Access Multiplexer (Module)
• EIP — Equipment installation procedure
• TDMA — Time Division Multiple Access

• IS — Information System
• VGA — Video Graphics Array
• SOS — Save Our Souls (Help!)
• AAF — Advanced Authoring Format
• DID — data item description
• WPS — Wireless Priority Service
• NCP — Network Control Protocol
• APN — An Access Point Name
• OMA — Open Mobile Alliance
• RT — Remote Terminal
• DTD — Document Type Definition (XML)
• LIU — Line Interface Unit
• WAR — Weekly Activity Report
• SPGA — Staggered Pin Grid Array
• ADT — American District Telegraph Company
• EMS — Element Management System (ATM)
• LU — Logical Unit
• EEHO — Either End Hop Off
• CSA — Canadian Standards Association (like UL)
• LRC — Learning Resource Center
• EFS — Encrypting File System
• VC — Virtual Channel
• SAN — System Area Network
• NE — North-East
• PDS — Planetary Data System
• DCS — Digital Cross-Connect
• PIM — Personal Information Manager
• POE — power over ethernetinjector
• MOL — Manned Orbiting Laboratory
• WINS — Windows Internet Name Service
• BIU — Bus Interface Unit
• ODBC — Open Database Connectivity
• SD — Software Development
• TRLR — Trailer
• LSF — Line Spread Function
• MEID — Mobile Equipment Identifier
• TCPA — Telephone Consumer Protection Act
• MCC — Mission Control Center (JSC)
• NNM — Network Node Manager
• CPN — Cisco Powered Network
• ASARS — Advanced Synthetic Aperture Radar System
• OTA — Office of Technology Assessment (U.S.; abolished by Congress, Fall 1995)
• AIN — Advanced Intelligent Network
• DL — Digital Library
• ABN — Abnormal
• ECP — Encryption Control Protocol
• IESG — Internet Engineering Steering Group
• TCIC — Trunk Circuit Identification Code
• TE — Test Equipment
• FE — Finite Element

• DAT — Digital Audio Tape
• NCSC — National Computer Security Center (NSA)
• ATC — Advanced Technology Center
• OCC — Occupancy
• SLAM — Scanning Laser Acoustic Microscope
• CAPS — Call Attempts Per Second
• LT — Line Termination
• DII — Defense Information Infrastructure
• SUS — Suspension
• ACT — Activity
• PROM — Programmable Read-Only Memory
• EX — Exercise
• FAA — Federal Aviation Agency
• BOD — Bandwidth on Demand
• SRS — Software Requirements Specifications
• ETS — European Telecommunication Standard
• JCL — Job Control Language
• TE — Terminal Equipment
• DEC — Decimal
• EMCON — Electromagnetic Emission Control
• IRS — Inertial Reference System
• CAMA — Centralized Automatic Message Accounting
• FMC — Fixed Mobile Convergence "Mobile UC or Unified Communications over Wireless"
• ORB — Object Request Broker
• ACF — Access Control Field
• DAL — Dedicated Access Line
• NIC — Network Interface Controller
• TDOA — Time Difference Of Arrival
• IRQ — Interrupt Request
• HEX — Hexadecimal (base 16)
• DIS — Draft International Standard
• ACAP — Application Configuration Access Protocol
• FWA — Fixed Wireless Access
• DSN — Defense Switched Network
• DID — Digital Information Display
• 10BASE-T — 10 Megabits per second, Baseband, Twisted pair
• TOA — Time Of Arrival
• MOD — Modify
• CNM — Customer Network Management
• CBR — Constant Bit Rate
• AWACS — Airborne Warning And Control System
• SAR — synthetic aperture radar (satellite)
• BHCA — Busy Hour Call Attempt
• DSS — Digital Signature Standard
• MLP — Mobile Location Protocol
• TDM — Time Division Multiplexer
• AP — access point
• ATA — Analog Telephone Adapter
• VSAT — Very Small Aperture Terminal (satellite service)
• CER — Cell Error Ratio

• Y — Yes
• IEEE — Institute of Electrical and Electronics Engineers
• TXM — Transmission X-ray Microscope
• ISOC — Internet Society
• DCS — Digital Cellular System
• COMDEX — Computer Dealers Exposition
• VLSI — Very-Large-Scale Integration
• TTY — Teletype Telex Machine
• CTU — Central Terminal Unit
• B3G — Beyond Third Generation
• CPS — characters per second
• SCN — Switched Circuit Network
• VMS — Virtual Memory System
• METRO — Metropolitan
• RT — Response Time
• EIGRP — Enhanced Interior Gateway Routing Protocol
• NTP — Network Time Protocol
• LR-WPAN — Low-Rate Wireless Personal Area Network
• COPS — Common Open Policy Service
• WTLS — Wireless Transport Layer Security
• YABA — Yet Another Bloody Acronym
• AMSS — Automatic Message Switching System
• AMPS — Advanced Mobile Phone System
• BTC — Botswana Telecommunications Corporation
• ACLR — Adjacent Channel Leakage Ratio
• BELLCORE — Bell Communications Research, Inc.
• MX — Mixer
• WAIS — Wide Area Information Server
• SL — Single Line
• DCN — Disconnect
• AMR — Automated meter reading also known as Automatic Meter Reading
• B6ZS — Bipolar 6 Zero Substitution
• DPL — Digital Private-Line
• EMEA — Europe, Middle East and Africa
• SWAP — Shared Wireless Access Protocol
• ADB — Apple Desktop Bus
• CB — Common Battery
• SMI — Structure of Management Information
• PEM — Privacy-Enhanced Mail
• CDE — Common Desktop Environment
• MUSIC — MUltiple SIgnal Classification
• RAU — Radio Access Unit (Army)
• AM — Activity Manager
• DPL — Digital Power Line
• FEP — Front End Processor
• CI — Common Interface
• NRPB — National Radiological Protection Board
• CFNRY — Call Forwarding on No Reply
• SITA — Société Internationale de Télécommunications Aéronautiques
• PVD — Physical Vapor Deposition

• PIC — Peripheral Interface Controller
• ABBR — Abbreviation
• EST — Establish
• KAK — Key-Auto-Key
• MCP — Microsoft Certified Professional
• SPM — Scanning Probe Microscope
• AN — Access Node
• RLU — Remote Line Unit
• TSR — Telecommunications Service Request
• RADIUS — Remote Authentication Dial-In User Service
• DVMRP — Distance Vector Multicast Routing Protocol
• VT — Virtual Terminal
• MBWA — Mobile Broadband Wireless Access
• RMI — Remote Method Invocation
• A — Anode
• FEC — Forward Error Correction
• DTMF — Dual-Tone MultiFrequency
• FLM — First Line Maintenance
• DCE — Data Communication Equipment
• BTAM — Basic Telecommunications Access Method
• LPD — Low Probability of Detection
• SPA — Software Publishers Association
• QDR — Quad Data Rate
• 3GPP — Third Generation Partnership Project
• EULA — End User License Agreement (usually in reference to software)
• NES — Network Encryption System
• CDC — Connected Device Configuration
• MRT — Medical Response Team
• CGSA — Cellular Geographic Service Area
• VBA — Visual BASIC for Applications
• BS — Broadcast Satellite
• PS — Product Specification
• CAM — Content Addressable Memory
• JTF — Joint Task Force
• DC — Display Controller
• BIS — Business Information System
• OT — Office of Telecommunications
• Q — Quadrature
• TL1 — Transaction Language 1
• SMB — Server Message Block
• IAD — Integrated Access Device
• AFOSR — Air Force Office Of Scientific Research(USA)
• LT — Less Than
• PTP — Point to Point Transmission Service (electricity)
• CC — Country Code
• LAG — Link Aggregation Group
• B2B — Business-to-Business
• SF — Single Frequency
• IAB — Internet Architecture Board
• JRE — Java Runtime Environment

• DNIC — Data Network Identification Code
• DEMUX — Demultiplexer
• E — Echo
• NPA — Numbering Plan Area
• TCM — Trellis-Coded Modulation
• CPC — Continous Packet Compression
• BBM — Blackberry Messenger
• SPD — Serial Presence Detect
• DMS — Data Management System
• TDD — Time Division Duplex
• ASDE — Airport Surface Detection Equipment
• VOA — Voice Of America
• DN — Distinguished Name
• FDL — Facility Data Link
• UP — User Profile
• PMP — Project Management Professional
• SAI — Serving Area Interface
• PE — Probable Error
• JDK — Java Development Kit
• SA — Source Address
• TLK — Talk
• NSS — Network Switching Subsystem
• IRTF — Internet Research Task Force
• MSRN — Mobile Station Roaming Number
• DER — Distinguished Encoding Rules
• SONET — Synchronous Optical Network
• AIT — Automatic Identification Technology
• LISP — List Processing Language
• EIR — Equipment Identity Register
• RMS — Resource Management System
• PM — Phase Modulation
• EIA — Extended Interaction Amplifier
• DM — Domain Model
• TTY — teletype terminal
• VF — Voice Frequency
• DL — Data Link
• 2W — 2-Wire
• MDM — Mobile Device Management
• CQA — Certified Quality Auditor
• TOVS — TIROS Operational Vertical Sounder
• EFIS — Electronic Flight Information System
• AMPS — Advanced Mobile Phone Service (cellular phone standard)
• VPI — Virtual Path Identifier
• SDP — Software Development Plan
• BNC — Bayonet Neill-Concelman
• NIU — Network Interface Unit
• BSS — Base Station Subsystem
• TDD — Telecommunications Device for the Deaf
• EMI — Electro-Magnetic Interference
• TPC — The Phone Company

• ES — Emergency Service
• WHT — Walsh-Hadamard Transform
• DW — Deep Water
• CODEC — Coder/decoder
• VT — Vacuum Tube
• FEP — Front-End Processor
• AS — Access System
• ISM — Industrial, Scientific and Medical
• PG — Page
• PC — Peripheral Controller
• WWAN — wireless wide-area network
• CS — Convergence Sublayer (ATM)
• BSS — Basic Service Set
• CIAC — Computer Incident Advisory Capability
• DCS — Data Collection System (NOAA Polar Orbiting Satellites)
• SDP — Session Description Protocol
• VRML — Virtual Reality Modeling Language
• CRLF — Carriage-Return Line-Feed
• FRS — Family Radio Service
• ESP — Encapsulating Security Payload
• RPV — Remotely Piloted Vehicle
• IAT — Integrated Access Terminal
• DVB — Digital Video Broadcasting
• RDI — Remote Defect Indicator (UNI Fault Management)
• DISA — U.S. Defense Information Systems Agency
• SYM — Symmetric
• SIM — Subscriber Identity Module
• ASA — Acoustical Society of America
• NAT — Network Address Translation
• ETSI — European Telecommunications Standard Institute
• QI — Quality Indicator
• CAL — Calorie
• BSI — British Standards Institution
• AUI — Attachment Unit Interface
• LATA — Local Access and Transport Area
• C — Cost
• ER — Extended Range
• DUA — Directory User Agent
• NTU — Network Termination Unit
• IT — Integration Test
• STD — Subscriber Trunk Dialing
• WK — Week
• SZ — Seizure
• TFTP — Trivial File Transfer Protocol (ATM)
• PP — Polypropylene
• ANSI-41 — ANSI standard for mobile management
• CAVE — Cellular Authentication and Voice Encryption Algorithm
• LOO — Likelihood of Occurrence
• CVR — Crystal Video Receiver
• OSCAR — Orbiting Satellite Carrying Amateur Radio

• SIL — Solid Immersion Lens
• FTAM — File Transfer Access and Management
• JAN — Joint Army-Navy
• ADN — Abbreviated Dialing Number
• FRS — Frame Relay Service
• CCIR — International Radio Consultative Committee (French Acronym)
• NREN — National Research and Education Network
• NA — Network Adapter
• SAS — Special Access Surcharge
• TRMM — Tropical Rainfall Measuring Mission (US-Japan)
• DDL — Digital Data Link
• AC — Area Code
• AIF — Audio Interchange Format
• CSPDN — Circuit Switched Public Data Network
• MIDP — Mobile Information Device Profile
• IOC — Inter-Office Channel
• TC — Transmission Convergence (ATM)
• EM — Electromigration
• IDF — Independent Distribution Frame
• MLM — Multi-Longitudinal Mode
• EBS — Electron Bombarded Silicon
• SNA — System Network Architecture
• TTY — Text Teletype
• SCCP — Signalling Connection Control Part
• IPCP — Internet Protocol Control Protocol
• HSCSD — High-Speed Circuit-Switched Data
• FH — Frequency Hopping
• DS-0 — Digital Signal, Level 0
• CGA — Carrier Group Alarm
• UTP — unshielded twisted pair
• HLR — Home Location Register
• SMR — Specialized Mobile Radio
• NDVI — Normalized Difference Vegetation Index
• CVD — Chemical Vapor Deposition
• CP — Change Proposal
• 1FB — Single line, Flat Business rate;
• DPSK — Differential Phase Shift Keying
• GBPS — Gigabits per second
• FEXT — Far-End Cross Talk
• DACS — Digital Access Cross-connect System
• POP — Post Office Protocol
• TAD — Telephone Answering Device
• SB — Switchboard
• TSE — Toronto Stock Exchange
• DII — Dynamic Invocation Interface
• PDT — Portable Data Terminal
• SIL — Silence
• E — Electra
• GSM — Groupe Speciale Mobile
• PU — Physical Unit (IBM)

• OOP — Object-Oriented Programming
• DFE — Design For Environment
• CMOS — Complementary Metal Oxide Semiconductors
• DSCP — Differentiated Services Code Point
• CONUS — Contiguous United States
• TMSI — Temporary Mobile Subscriber Identity
• STN — Station
• 1-ESS — x-ESS series of Electronic Switching Systems
• SG — Signaling Gateway (IETF)
• DMI — Distributed Management Interface
• OWS — Operator Work Station
• DDD — Direct Distance Dialing
• ASYNC — Asynchronous
• DHD — Dial Home Device
• VLAN — Virtual Local Area Network
• DTN — Data Transfer Network
• IPVX — Internet Protocol version X
• TMS — Time Management System
• BCH — Bose-Chaudhuri-Hocquenghem Coding
• DPDU — Data Protocol Data Unit
• MV — Motion Vector
• APDU — Application Protocol Data Units
• CODASYL — COnference on DAta SYstems Languages
• FMS — Fraud Management System
• IPS — InPlane Switching
• PCI — Personal Computer Interface
• MAI — Multiple Access Interference
• SS1 — Signalling System 1 (500/20 Hz tones)
• RDS — Rate Determining Step
• XPS — X-Ray Photoelectron Spectroscopy
• ROW — Rest Of World
• 4GL — Fourth-Generation Language
• WCDMA — Wideband Code Division Multiple Access
• OBC — Onboard Computer
• DOR — Detailed Outage Report
• TSB — Telecommunication Standardization Bureau
• BS — Backing Store
• PVC — Permanent Virtual Connection
• GBT — Ground Based Tower
• CB — Citizens' Band
• OTDOA — Observed Time Difference of Arrival
• DNU — Do Not Use
• FDTD — Finite Difference Time Domain
• LSI — Large Scale Integration -> VLSI
• PSS — Performance Support System
• RJE — Remote Job Entry
• SMDS — Switched Multimegabit Data Service (ATM)
• AF — Assured Forwarding
• RECON — Reconnaissance
• DISN — Defense Information Systems Network

• IEC — Interexchange Carrier
• BMEWS — Ballistic Missile Early Warning System (bee-mews)
• PBT — Polybutylene Terephthalate
• CIRC — Cross-Interleaved Reed-Solomon Code
• RACH — Random Access Channel
• IRC — International Record Carrier
• ADC — Administration Center
• CAP — Capability
• FOSE — Federal Office Systems Exposition
• L2TPV3 — Layer 2 Tunneling Protocol Version 3
• IV&V — independent verification and validation
• SPX — Sequenced Packet Exchange
• RISC — Reduced Instruction Set Computing
• TAM — Telephone Answering Machine
• KSU — Key Service Unit
• EU — End User
• FRAD — Frame Relay Access Device
• T — Temperature
• SFX — Special Effects
• COAM — Customer Owned And Maintained
• EBCDIC — Extended Binary-Coded Decimal Interchange Code
• FITL — Fiber-In-The-Loop
• CBWFQ — Class Based Weighted Fair Queueing
• BLER — Block Error Rate
• DRFM — Digital Radio-Frequency Memory
• SMPTE — Society of Motion Picture and Television Engineers, Inc.
• TRS — Trunked Radio Systems
• TRS — Telecommunications Relay Service
• OSF — Open Software Foundation
• SAF — System Access Fee
• LD — Laser Diode
• ACE — Adaptive Communication Environment
• NAK — Negative Acknowledge
• FTNS — Fixed Telecommunications Network Services
• SIA — Securities Industry Association
• SLV — Satellite-Launch Vehicle
• LASA — Large Aperture Seismic Array
• TOP — technical/office protocol
• GMRS — General Mobile Radio Service
• DM — Differential Mode
• ASN.1 — Abstract Syntax Notation One
• C — Collector
• CMIP — Common Management Information Protocol (ATM)
• BSS — Base Station System
• FEM — Finite Element Method
• SDSL — Symmetric Digital Subscriber Line
• ACSE — Association Control Service Element
• RCC — Radio Common Carrier
• NAS — Network-Attached Storage
• FTTC — Fiber To The Curb光纤到路边

• VPA — Valid Peripheral Address
• 4 GIG — 4 Giga Intellectual Gadget
• ADC — Access Deficit Charge
• CNG — comfort noise generation
• SCCP — Signaling Connection Control Point
• O/S — Operating System
• VTS — Vessel Traffic Service
• RSS — Radio Service Software (Motorola)
• CIS — Computer and Information Science
• SWBD — Switchboard
• MTS — Message Transfer System
• IEEE-CS — Institute of Electrical and Electronics Engineers Computer Society
• BSID — Base Station Identity
• SISIR — Singapore Institute of Standards and Industrial Research
• DL — Definition List
• IEEE-SA — Institute of Electrical and Electronics Engineers - Standards Association
• CGA — Color Graphics Adapter
• IPM — Inches Per Minute
• TSO — Telecommunications Service Order
• FAS — Frame Alignment Signal
• ACC — Area Control Center
• CSC — Common Signaling Channel
• S/D — Source/Drain
• IMAP — Internet Mail Access Protocol
• TIFF — Tag Image File Format
• HFC — Hybrid Fiber/Coaxial network
• ASAR — Advanced Synthetic Aperture Radar 
• DAP — Distributed Array Processor
• ODS — Operational Data Store (knowledge management)
• VHSIC — Very High-Speed Integrated Circuit
• DPCM — differential pulse code modulation
• SDU — Signal Distribution Unit
• UMA — Unlicensed Mobile Access
• TTL — ToS and Time-to-Live
• RSS — root-sum-square
• SQ — Service Quality
• FEA — Finite Element Analysis
• CS-PDU — Convergence Sublayer - Protocol Data Unit
• ETF — Early Termination Fee
• ACP — Access Control Point
• 2G — Second Generation Wireless Systems
• EMR — Electromechanical Relay
• CAC — Connection Admission Control (Asynchronous Transfer Mode)
• OSP — Outside Plant
• SPIN — Service Provider Identification Number
• SLIC — Subscriber Line Interface Circuit
• REA — Rural Electrification Administration (US)
• MAJ — Major
• MFLOPS — Millions of Floating Point Operations per Second
• BMS — Business Management System

• DGPT — Directorate General of Posts and Telecommunications
• CP — Call Processing
• NII — National Information Infrastructure (USA)
• DSI — Digital Speech Interpolation
• SRM — Scalable Reliable Multicast
• COM — Comedy Central
• CAM — Common Access Method
• AP — Action Point
• VG — Voice Grade
• SVC — Switched Virtual Circuit (ATM)
• SM — Service Module
• OXCO — Oven-Controlled Crystal Oscillator
• CCA — Carrier-Controlled Approach
• CS — Central Station
• WAYP — White and Yellow Pages
• ALT — Accelerated Life Test
• LDP — Label Distribution Protocol
• PIC — Programmable Interrupt Controller
• OOK — On/Off Keying
• ESCA — photoelectron spectroscopy for chemical analysis
• DDU — Disk Drive Unit
• CALEA — Communications Assistance for Law Enforcement Act
• HSPA — High Speed Packet Access
• WSFL — Web Services Flow Language
• TELNET — Telecommunications Network Protocol
• CLK — Clock
• ST — Such That
• IPS — Instructions Per Second
• BCDIC — Binary Coded Decimal Interchange Code
• 4G — Fourth Generation Wireless Systems
• RDMA — Remote Direct Memory Access
• ASE — Application Service Element
• OSS — Operations Support System
• DFG — difference-frequency generation
• SSRC — Synchronization Source
• ISG — Information Systems Group
• EECM — End-to-End Call Manager
• RAU — Remote Access Unit
• DTU — Data Transfer Unit
• WDN — Wireless Developer Network
• FGA — Feature Group A
• BA — Behaviour Aggregate
• SD — Speed Dial
• CLETS — California Law Enforcement Telecommunication System
• CGI — Cell Global Identity
• VQV — Voice Quality Value
• YA — Yet Another
• LFACS — Loop Facility Assignment and Control System
• FECN — Forward Explicit Congestion Notification (ATM)
• AVR — Automated Voice Response

• ARSR — Air Route Surveillance Radar
• CE — Channel Element
• COO — Cell of Origin
• AWT — Agence Wallonne des Télécommunications
• CGI — Computer Graphics Interface
• PAM — Payload Assist Module
• ASD — Alternative Service Delivery
• DTI — Digital Trunk Interface
• CPC — Calling Party Control
• CLDC — Connected Limited Device Configuration
• W-CDMA — Wideband Code Division Multiple Access
• CNG — Fax Calling Tone
• ABM — Asynchronous Balanced Mode
• SRR — Search and Rescue Region
• ANC — Access Network Controller
• CCR — Customer Controlled Reconfiguration (Sprint)
• NWK — Network
• IMP — Interface Message Processor
• HUP — Hook-UP
• NCAR — National Center for Atmospheric Research (US)
• M/W — MicroWave
• NCC — Network Control Center (GSFC)
• P — Priority
• ATS — Air Traffic Services
• SSM — Spread Spectrum Modulation
• MH — Message Handler
• V — Variable
• HTML — Hyper-Text Markup Language
• CT — Computer Terminal
• RGN — Region
• ACF — Advanced Communications Function (IBM)
• 3-D — 3-Dimensional
• MHO — My Humble Opinion
• DARTS — Design Approach for Real-Time Systems
• ALB — Analog Loopback
• SCU — System Control Unit
• INE — Intelligent Network Element
• WSDL — Web Services Description Language
• NDS — Novell Directory Services
• UART — Universal Asynchronous Receiver/Transmitter
• EGSM — Extended Global System for Mobile Communications
• IPLC — International Private Leased Circuit
• TOMS — Total Ozone Mapping Spectrometer (satellite Instrument)
• IG — Interface Group
• DCA — Dynamic Channel Assignment
• SCPC — single channel per carrier
• LDN — Local Directory Number
• RNX — Restricted Numeric eXchange
• LSW — Least Significant Word
• CHTML — Compact Hypertext Markup Language

• CRB — Cramer-Rao Bound
• ECM — Error Correction Model
• CCLC — Carrier Common Line Charge
• MSW — Most Significant Word
• VESA — Video Electronics Standards Association
• LIS — Lightning Imaging Sensor
• LOP-P — Loss Of Pointer - Path
• COT — Central Office Terminal
• SSM — Synchronization Status Message
• SETI — Search for Extraterrestrial Intelligence
• LCR — Least Cost Routing
• DUV — Deep Ultraviolet
• FDD — Frequency Division Duplex
• AMA — automatic message accounting
• SFN — Single Frequency Network
• LRC — Longitudinal Redundancy Check
• PLL — Phase Locked Loop
• DLCI — data link connection identifier
• CTI — Computer Telephony Integration
• DLP — Data Link Processor
• GDK — GIMP (GNU Image Manipulation Program) Drawing Kit
• CND — Calling Number Display
• EA — Extended Address Field Bit
• ILEC — Incumbent Local Exchange Carrier
• BAN — Building Area Network
• CCNA — Cisco Certified Network Administrator
• AAS — advanced automation system (FAA)
• CMRS — Commercial Mobile Radio Service
• CPG — Converged Packet Gateway
• RICK — Repeater Interface Communications Kit
• DAS — Data Acquisition System
• BOSS — Binary Object Storage System
• WDA — Wireless Digital Assistant
• BHCA — Busy Hour Call Attempts
• TAX — Trunk Automatic Exchange
• CSU — Channel Service Unit
• SR — Slow Release
• CLEC — Competitive Local Exchange Carrier
• DDLD — Direct Dial Long Distance
• IRF — Impulse Response Function
• EDFA — Erbium-Doped Fiber Amplifier
• EIR — Excess Information Rate
• CIP — Carrier Identification Parameter
• FOD — Fax on Demand
• RADINT — Radar Intelligence
• MSC — Mobile Switching Center
• IWF — Interworking Function
• SNIX — Single Noise Interference Xterminator
• RTC — Real-Time Control
• # — Number sign, octothorp; special function key

• MTD — Moving Target Detection
• LP — Line Pair
• NF — Noise Factor
• DIV — Divisionsion
• PTP — Point To point Protocol
• FXS — Foreign Exchange Subscriber
• DOCSIS — Data over Cable Service Interface Specification
• EVA — Electronic Video Agent
• TSP — Telecommunications Service Priority
• VLSI — Very Large-Scale Integration
• SN — Service Number
• TACACS — Terminal Access Controller Access Control System
• 3G — 3rd Generation Wireless Format
• DNC — Do Not Call
• PSN — Packet Switched Network
• DLL — Digital Local Line
• DDI — Direct Dialing Incoming
• WE — Western Electric
• OML — Object Model Library
• WTS — Wireless Telecommunications Symposium
• MLA — Modern Language Association
• PTO — U.S. Patent And Trademark Office
• DAC — Digital-To-Analog Converter
• SSMA — Spread-Spectrum Multiple Access
• MSDP — Multicast Source Discovery Protocol
• CAM — Computer-Aided Manufacturing
• SN — Stock Number
• EBIC — Electron Beam Induced Current
• FSK — Frequency Shift Keying
• UAT — Universal Access Transceiver
• NTDS — Naval Tactical Data System
• TDRSS — Tracking and Data Relay Satellite System
• DXC — Digital Cross Connect
• DC — Device Control
• PDL — Positioning Data Link
• ADCCP — Advanced Data Communication Control Procedures
• CIP — Continuous Improvement Program
• IPR — Intellectual Property Right
• RX — Receive
• SCO — Synchronous Connection Oriented
• ELFEXT — Equal-Level Far-End Cross-Talk
• FLL — Fixed-Loss Loop
• IS 41 — Interim Standard 41 (Inter-Cellular Network Communication Protocol)
• SIMT — Système interbancaire marocain de télécompensation
• TCP/IP — Transmission Control/Internet Protocol
• TUR — Trunk Utilization Report
• RSL — Restricted Service License
• VSAM — Virtual Storage Access Method
• WSP — Wireless Service Provider
• ASN.1 — Abstract Syntax Notation 1

• LIF — Logical Interchange Format
• FDI — Feeder Distribution Interface
• PARC — Palo Alto Research Center
• PTI — Payload Type Indicator
• GTP — GPRS (General Packet Radio Service) Tunneling Protocol
• ETOC — Electronic Table of Contents
• RDBMS — Relational Data Base Management System (Oracle)
• LRQ — Location Request
• DA — deca
• SCM — Single-Carrier Modulation
• URN — Uniform Resource Namespace
• MMC — Microsoft Management Console (Microsoft)
• CIP — Channel Interface Processor
• MITI — Ministry of International Trade and Industry
• AAL5 — ATM (Asynchronous Transmission Mode) Adaptation Layer 5
• CCITT — Comit? Consultatif International T?l?graphique et T?l?phonique
• ET — Electronic Transmission
• RXQUAL — Received Signal Quality
• CPH — Call Party Handling
• MPI — Minimum Picture Interval
• CPOP — Circuit Precedence Over Packet data
• CTIA — Cellular Telecommunications Industry Association
• LIM — Line Isolation Monitor
• BY — Busy
• SDHLR — Super-Distributed Home Location Register
• CV — Coding Violation
• ARM — Asynchronous Response Mode
• PUC — Public Utility Commission (electricity)
• DMT — Discrete Multi-Tone Technology
• ISI — Intersymbol Interference
• CAMEL — Customized Applications for Mobile-network Enhanced Logic
• ESPN — Entertainment and Sports Programming Network
• FGD — Feature Group D
• CDM — Conceptual Data Model
• DCF — Distributed Coordination Function
• MA — Maintenance Action
• NE — Network Element
• MGC — Multimedia Gateway Controller
• PNP — Plug-and-Play
• LUNT — Line Unit Network Termination
• SIP — Session Initiation Protocol
• TEI — Terminal Endpoint Identifier
• ACA — Adaptive Channel Allocation
• ICL — Inserted Connection Loss
• MA — Message Analysis
• RMON — Remote Monitoring
• AOS — Alternate Operator Service
• BDE — Borland Database Engine
• FNN — Full National Number
• L2F — Layer 2 Forwarding protocol

• CAR — committed access rate
• CIC — Carrier Identification Code
• PIM — Protocol Independent Multicast
• CPE — Customer Premise Equipment
• NTE — Network Terminating Equipment
• PMT — Program Management Team
• STMR — Sidetone Masking Rating (telecommunications)
• PNP — Positive-Negative-Positive
• GI — Graded-Index
• CRV — Call Reference Value
• L2TP — Layer 2 Tunneling Protocol
• EDC — Electronic Dispersion Compensator
• MC — Maintenance Control
• LAAS — Local Area Augmentation System
• CEPT — Conférence Européenne des Administrations des Postes et des Télécommunications
• CDV — Cell Delay Variation(ATM)
• VPX — Virtual Path Cross-Connect
• SCCS — Switching Control Center System
• SE — Southeast
• MAG — Mobile Access Gateway
• WFA — Wait for Answer
• GRUB — Greedy Reclamation of Unused Bandwidth
• BOM — Bit-Oriented Message
• TLT — Test Loop Translator
• WTP — Wireless Transaction Protocol
• VPWS — Virtual Private Wire Service
• ALI — Automatic Location Information
• BDSL — Broadband Digital Subscriber Line
• DLU — Digital Line Unit
• ILETS — International Law Enforcement Telecommunications Seminar
• NRP — Network Resource Planning
• COMB — Combined
• VTAM — Virtual Telecommunication Access Method
• B-CPE — Broadband Customer Premises Equipment
• TOC — Telecommunication Operations Center
• MEAS — Measure
• WARC — World Administrative Radio Conference
• TDWR — Terminal Doppler Weather Radar
• ULL — Unbundled Local Loop
• BATM — Basic Telecommunication Access Method
• LANE — Local Area Network Emulation
• AWG — arrayed waveguide grating
• FCA — Fixed Channel Allocation
• MSI — Maritime Safety Information
• DICOM — Digital Imaging and Communications in Medicine
• SIM — Subscriber Identification Module
• F — Frequency
• UBR — Unspecified Bit Rate
• CRTS — Cellular Radio Telecommunications Service
• GTB — Global Telecom Brokers

• FOIP — Fax Over Internet Protocol
• CLCC — Ceramic Leaded Chip Carrier
• TDR — Time-Domain Reflectometry
• CACH — Call Appearance Call Handling
• FTTK — Fibre To The Kerb
• SSAP — Source Service Access Point
• TD-CDMA — Time Division - Code Division Multiple Access
• NSAP — Network Service Access Point
• ETN — Electronic Tandem Network
• GAN — Global Area Network
• IPOATM — Internet Protocol over ATM
• NCF — Network Control Facility
• VN — Virtual Network
• EDSX — Electronic Digital Signal Cross-Connect
• BSA — Basic Service Area
• CSIRO — Commonwealth Scientific and Industrial Research Organization
• MMM — Mobile Media Mode
• INTELSAT — International Telecommunications Satellite
• 100VG — 100 Voice Grade (IEEE 802.12 AnyLAN Standard)
• STU — Secure Telephone Unit
• LBR — Low Bit Rate
• PSO — Professional Services Organization
• BSC — Bi-Synchronous Communications
• DPT — Dynamic Packet Transport
• SAT — Satellite
• NW — North West
• DQDB — Distributed Queue Dual Bus
• BAN — Billing Account Number
• STM — Synchronous Transfer Mode
• BIS — Brought Into Service
• SCR — Sustainable Cell Rate
• ILD — International Long Distance
• DTE — Digital Terminal Equipment
• CES — Circuit Emulation Service
• ERL — Echo Return Loss
• DTAP — Direct Transfer Application Process
• 4WA — Four Wire Analog
• MR — Mobile Router
• ALOC — Average Length Of Call
• ADPCM — Adaptive Differential Pulse Code Modulation
• SPE — Synchronous Payload Envelope
• 3G — Third Generation (mobile communication system)
• RADIUS — Remote Authentication dial In User Service
• 3G HSPA — Third-Generation High-Speed Packet Access
• ADPC — Automatic Data Processing Center
• PACS — Personal Access Communications System
• MBE — Molecular Beam Epitaxy
• LS — Loop Start
• BIND — Berkeley Internet Name Domain
• ATSC — Advanced Television Systems Committee

• PD — Pulse Duration
• NCP — Network Control Program
• GRX — GPRS Roaming Exchange
• FCA — Free Carrier Alongside
• JISC — Japanese Industrial Standards Committee
• TM — Thematic Mapper (Landsat)
• B8ZS — Binary Eight Zero Substitution
• FAC — Forced Authorization Code
• EMF — Event Management Framework
• ESN — Electronic Serial Number
• REPT — Report
• BUFR — Binary Universal Form for the Representation (of data)
• * — Star, special function key
• RCU — Radio Control Unit
• TACSAT — Tactical Satellite
• IBSS — Independent Basic Service Set
• STD — Secondary Telecom District
• SSN — Switched Service Network
• UDP — Up Down Pair
• BT — Bluetooth Tablet
• DBRNC — deciBel Relative to Noise in a Circuit
• DXF — Data Exchange Format
• CCCH — Common Control Channel
• WNMS — Wireless Network Management System
• ECS — Environmental Control System (Subsystem)
• MTA — Message Transfer Agents (Internet)
• FC — Frame Control
• GERAN — GSM (Global System for Mobile communications) Edge Radio Access Network
• BORSCHT — Battery feed, Overvoltage protection, Ringing, Signaling, Coding, Hybrid, and Testing
• F/W — Firmware
• MMDS — Multichannel Multipoint Distribution Service
• SINAD — SIgnal-to-(Noise And Distortion) ratio
• VCI — Virtual Channel Identifier
• UPT — Universal Personal Telecommunications
• PTT — Push to Talk Technology
• SRL — Singing Return Loss
• IPRC — Intellectual Property Rights Committee
• 2G — Second generation cellular
• RIPE NCC — Reseaux IP Europeens Network Coordination Centre
• CMA — Communications Management Association
• BT — Burst Tolerance
• SA — Selective Availability (on GPS transmissions)
• SRA — Seamless Rate Adaptation
• DLT — Delete
• DPA — Distributed-Power Architecture
• ADM — Administration Building
• SCR — System Change Request
• NT — New Technology, also Windows NT
• UTL — Utility
• VSAT — Very Small-Aperture Terminal

• MP — Modulation Parameter
• DNSIX — Defense Network Security Information Exchange
• ETOM — Enhanced Telecom Operations Map
• EPP — Enhanced Parallel Port (PC)
• RTB — Retransmission Buffer
• ATCA — Advanced Telecom Computing Architecture
• ATTRA — Appropriate Technology Transfer for Rural Areas
• BABT — British Approvals Board for Telecommunications
• CASE — Computer-Aided Software Engineering
• TD — Transmit Data
• BAF — Bellcore AMA (Automatic Message Accounting) Format
• RDT — Recall Dial Tone
• MTI — Moving Target Indicator
• FTTP — Fiber To The Premises
• OMP — Open Management Platform
• FTS — Federal Telecommunications System
• DCAS — Downloadable Conditional Access System
• PY — person-year
• TRIG — Trigger
• ATS — Abstract Test Suite
• COC — Central Office Connection
• PLCP — Physical Layer Convergence Procedure
• ZCZ — Zero Correlation Zone
• FFH — Fast Frequency Hopping
• DPNSS — Digital Private Network Signaling System
• STM — Scanning Tunneling Microscopy
• FDOA — Frequency Difference Of Arrival
• SPID — Service Profile Identifier
• HFC — Hybrid Fiber Coaxial
• CPAP — Customer Premises Access Profile
• 3GPP — Third-Generation Partnership Project
• RCP — Right-Hand Circular Polarization
• CID — Craft Interface Device
• LH — Link Handler
• PTT — Push to Talk Testing
• MAP — Mobile Application Part
• LB — Local Battery
• TCB — Telecommunication Certification Body
• NSE — Network Software Environment
• RDT — Remote Digital Terminal
• RM-ODP — Reference Model for Open Distributed Processing
• FPS — Framing Pattern Sequence
• BPP — Billed Party Preference
• CCP — Compression Control Protocol
• EFCI — Explicit Forward Congestion Indication (ATM)
• COFA — Change Of Frame Alignment
• CTE — Computer Telephony Engineer
• CAPTAIN — Character And Pattern Telephone Access Information Network
• NTSC — National Television Standards Committee
• NDIS — Network Driver Interface Specification (Microsoft Windows NT)

• RFR — Radio Frequency Radiation
• IR — International Roaming
• CERN — Conseil Europeen Pour La Recherche Nucleaire
• EEROM — Electronically Erasable Read-Only Memory
• DEM — Digital Elevation Model
• PTE — Path Terminating Equipment (SONET)
• CAAS — Communications-as-a-Service
• FIOS — Fiber Optic Services
• CBQ — Class-Based Queuing
• ET — Exchange Terminal
• BUS — Broadcast and Unknown Server
• CDA — Communications Decency Act's
• MF — Multiple Frequency
• OSA — Open System Architecture
• DTL — Defense Telephone Link
• ESCON — Enterprise System Connection
• CON — Concentrator
• SCH — Synchronization Channel
• NEMP — Nuclear Electromagnetic Pulse
• DOD — Direct Outward Dialing
• DSSSL — Document Style Semantics and Specification Language
• TU — Transmission Unit
• DRQ — Disengage Request
• ETSI — European Telecommunications Standards Institute
• KSPS — KiloSymbols Per Second
• INSAT — Indian National Satellite
• NC — Network Channel
• FMR — Follow Me Roaming
• ENV — Environment
• BCSM — Basic Call State Model
• LCF — Location Confirm
• TT — Text-Telephone
• SN — Switching Network
• AQP — Association for Quality and Participation
• WSA — Wireless Security Auditor
• EM — Element Manager
• FAT — Final Acceptance Testing
• ARPT — Autorité de Régulation des Postes et Télécommunications
• WFG — Wireless Firewall Gateway
• DMS — Defense Messaging System
• PSDN — Public Switched Digital Network
• CSAR — Combat Search and Rescue
• OMF — Object Management Framework
• PMOS — P-channel Metal Oxide Semiconductor
• TBPS — Terabits Per Second
• DXI — Data Exchange Interface
• LAPB — Link Access Protocol-Balanced
• TDM — Time Division Multiplexing
• MDN — Mobile Directory Number
• DECCO — DISA Defense Commercial Communications Office

• RSN — Regional Service Network
• NAU — Network Addressable Unit
• DPBX — Digital Private Branch Exchange
• EST — Electroshock Therapy
• APPC — Advanced Program-to Program Communications
• EC — Equipment Controller
• CSR — Customer Service Request
• WTNM — Working Telephone Number Management
• DAC — Digital to Analog Converter-Audio
• ACU — Automatic Calling Unit
• RLS — Recursive Least Squares
• NMC — Network Management Center
• BHCC — Busy Hour Call Completions
• LDI — Long Distance Interconnect
• DL — Downlink Message
• DE — Discard Eligibility (ATM)
• 3GSM — Third-generation Global System for Mobile (communications)
• QOI — Quality of Information
• UMTS — Universal Mobile Telecommunications Service
• NAP — Network Access Point
• AGCH — Access Grant Channel
• ECTF — Enterprise Computer Telephony Forum
• CRBT — Color Ring Back Tone
• FAW — Frame Alignment Word
• MFC — Multi-Frequency Code
• DNI — Data Network Interface
• PTT — Push to Talk Taster
• ALCAP — Access Link Control Application Protocol
• WIS — WAN (Wide Area Network) Interface Sublayer
• SMS — Service Management System
• WFT — Wireline Formation Test
• FRF-LMI — Frame Relay Forum - Local Management Interface
• RDSS — Radio Determination Satellite Service
• VISSR — visible and infrared spin scan radiometer (GOES)
• UMTS — Universal Mobile Telecommunication System
• VADB — Virtual Auto Dial Backup
• E2E — End-to-End
• RRC — Root Raised-Cosine
• CALS — Computer Aided Acquisition and Logistic Support
• LCP — Local Control Point
• LLA — Link Level Access
• MAU — Multistation Access Unit
• DPDT — Double-Pole Double-Throw
• GSTN — General Switched Telephone Network
• 3GIP — Third Generation Internet Protocol
• FIRST — Forum of Incident Response and Security Teams (CERT)
• LORAN — Long Range Aid to Navigation System
• TBCD — Telephony Binary Coded Decimal
• ALI — Automatic Location Identifier
• TCA — Threshold Crossing Alert

• OLS — Optical Line System
• BHA — Busy Hour Attempts
• CSTA — Computer Supported Telecommunications Applications
• JWP — Joint Working Party
• EV — electronvolt
• TSC — Test System Controller
• UNI — User-Network Interface
• ARFA — Allied Radio Frequency Agency
• GTM — Go to Meeting
• DDU — Digital Data Unit
• CSR — Customer Service Report
• MPU — Main Processor Unit
• TC — Technical Committee (HL7)
• HDTV — High-Definition Television
• EVC — Electronic Voucher Charging
• MIS — Marketing Intelligence System
• S/N — Signal-to-Noise ratio
• WVOIP — Wireless Voice over Internet Protocol
• AMTFT — Active Matrix Thin Film Transistor
• CFOT — Certified Fiber-Optic Technician
• CDV — Compressed Digital Video
• DECT — Digital Enhanced Cordless Telecommunication
• SM OFC — Single-Mode Optical Fiber Cable
• RPCU — Radio Port Control Unit
• UCF — Unregistration Confirm
• LN — Line
• BCS — British Computer Society
• VOB — Voice Over Broadband
• CRS — Cell Relay Service
• FIFO — first-in, first-out
• CCSA — Common Control Switching Arrangement
• BB — Blackberry
• PTM — Packet Transport Mode
• LSAP — Link Service Access Point
• DUN — Dial-Up Networking
• BNCC — Base Network Control Center
• ACF — Access Coordination Function
• DIL — Direct Inward Line
• LMT — Lightwave Microcell Transceiver
• VSM — Vestigial Sideband Modulation
• NICT — National Institute of Information and Communications Technology
• RADSL — Rate Adaptive Digital Subscriber Line
• MMB — Middle Mouse Button
• SDSL — Symmetrical Digital Subscriber Line
• GMSS — Global Mobile Satellite System
• IDCP — Internet Device Control Protocol
• QOTS — Quality Of Telephone Services
• USF — Universal Service Fund
• AIS-L — Alarm Indication Signal - Line
• SGSN — Serving GPRS (General Packet Radio Service) Support Node

• LRM — Long Reach Multimode
• VAN — Value-Added Network
• TON — IEEE/ACM Transactions On Networking
• SEM — Scanning Electron Microscopes
• SMMR — Scanning Multichannel Microwave Radiometer
• PSLV — Polar Satellite Launch Vehicle (Indian Space Research Organization; India)
• NLM — NetWare Loadable Module
• DCS — Defense Communications System
• BIC — Bus Interface Controller
• IVP — Integrated Voice Protocol
• FI — Format Identifier
• GS — Ground Start
• CFR-47 — Code of Federal Regulations Title 47 (FCC)
• AIU — Analog Interface Unit
• DTU — Date/Time Update
• RADARSAT — Radar Satellite
• BTS — Base Transceiver Station (cellular)
• MVDS — Microwave Video Distribution System
• DPST — Double-Pole Single-Throw
• ATB — Above-Ground Telecommunications Backbone
• MBMS — Multimedia Broadcast/Multicast Service
• SMS — System Management Server
• CSDU — Core Service Data Unit
• 4WAI — Four-Wire Analog Interface
• ATU-C — ADSL (Asymmetric Digital Subscriber Line) Transceiver Unit - Central office end
• WIN — Wireless Intelligent Network
• LOB — Line Of Bearing/Balance
• MGCP — Multimedia Gateway Control Protocol
• SYSADM — System Administrator
• TP-PMD — Twisted Pair Physical Medium Dependent
• ARD — Automatic Ring Down
• PDSO — Packet Data Security Overlay
• MILNET — Military Network
• CTO — Commonwealth Telecommunications Organisation
• ANAC — An Automatic Number Announcement Circuit
• B-ISDN — Broadband ISDN
• ATRAC — Adaptive Transform Acoustic Coding
• CLD — Cross-Layer Design
• FLN — Fixed Line Network
• UIT — Union Internationale des Télécommunications
• MTP — Message Transfer Part
• ANS — Advanced Network Services
• BPSK — Binary Phase-shift Keying
• MB — Measured Business
• LI — Length Indicator
• ANT — ADSL Network Terminator
• EC — Entropy Coding
• AAV — Alternate Access Vendor
• CBMS — Computer-Based Message System
• VO — Voice Only

• CAS — Column Address Strobe
• FGDC — Federal Geographic Data Committee's
• SDNS — Secure Data Network System
• LMDS — Local Multipoint Distribution Service
• QS — Quasi-Synchronous
• LCAS — Link Capacity Adjustment Scheme
• RAD — Recorded Announcement Device
• TCS — Telephony Control Specification
• IDLC — Integrated Digital Loop Carrier
• BRAN — Broadband Radio Access Network
• CC — Composite Clock (SONET)
• CDVT — Cell Delay Variation Tolerance
• LCGN — Logical Channel Group Number
• CCR — Current Cell Rate (ATMF)
• CDDI — Copper Distributed Data Interface
• LSP — Label Switched Path
• AECT — Association for Educational Communications and Technology's
• SCORM — Shareable Content Object Reference Model
• AT — Attenuation
• DCMES — Dublin Core Metadata Element Set
• RLA — Received Level Average
• GFC — Generic Flow Control (ATM)
• PCS — Personal Communications Services
• SLIP — Serial Line Internet Protocol
• GOMP — Get Off My Phone
• CATI — Computer-Assisted Telephone Interviewing
• EC-N — Electrical Carrier (n=a number, e.g., EC-4)
• PWM — Pulse width modulation
• PFE — Power Feed Equipment
• PSN — Public Switched Network
• USA — Underground Service Alert
• SSU — Synchronization Supply Unit
• MCR — Minimum Cell Rate (ATM)
• VNL — Via Net Loss
• ARCNET — Attached Resource Computer Network
• BTP — Business Telecom Products, Inc.
• FOC — Fiber-Optic Cable
• PMMA — Polymethyl Methacrylate
• BT — Back Trace
• WAAS — Wide Area Augmentation System
• KEK — Key Encrypting Key
• DUV — Data-Under-Voice
• PSQM — Perceptual Speech Quality Measure
• LEED — Low-energy Electron Diffraction
• P2P — Person-to-Person
• PMT — Photo Multiplier Tube
• ATL — Advanced Technology Laboratory
• RS-422 — Recommended Standard 422 (ANSI/EIA standard for transmitting serial data)
• TSG — Telephone Security Group
• FMS — Fixed Mobile Substitution

• TRX — Tandem Repeater eXchange
• RP — Radio Port
• 802.11 HR — High data Rate IEEE 802.11 Wireless LAN protocol
• CCCI — Command, Control, Communications and Intelligence
• BIOS — Basic Input-Output System
• DS-3 — Digital Signal, Level 3
• LTU — Line Terminating Unit
• ATD — Advanced Technology Demonstration
• SQL — Specified Quality Level
• PHY — Physical Layer
• PTCL — Pakistan Telecommunication Company Ltd
• LCU — Lightweight Computer Unit
• DMT — Discrete Multi-Tone
• SMT — station management (protocol)
• LSC — Link State Control
• LPDP — Local Policy Decision Point
• VOFR — Voice Over Frame Relay
• CACM — Communications of the ACM
• AFI — Authority and Format Identifier
• SGCP — Simple Gateway Control Protocol
• TP — Transition Point
• TCM — Time Compression Multiplexer
• VDR — Voice Digitization Rate
• PCCA — Portable Computer Communications Association
• BAP — Bandwidth Allocation Protocol
• FHSS — Frequency Hopping Spread Spectrum
• AEA — American Electronics Association's
• TPS — Telephone Preference Service
• TP — Telephone Pole
• VAD — Voice Activity Detection
• AAV — Alternative Access Vendor
• ACNA — Access Customer Name Abbreviation
• EC — Echo Cancelling
• PLCP — Physical Layer Convergence Protocol (ATM)
• CDA — Communications Decency Act of 1996
• AB — Answer Back
• CLOS — Clear Line Of Sight
• NMC — Nortel Matra Cellular
• PLE — Path Length Efficiency
• TCC — Transmission Control Code
• WAE — Wireless Application Environment
• DMT — Digital-Discrete Multi-Tone
• STA — Science and Technology Agency (Japan)
• AAP — Alternate Access Provider
• KTS — Key Telephone System
• OSD — Onscreen Display
• BSRF — Basic System Reference Frequency
• DTR — Down-Time Ratio
• PJC — Pointer Justification Count
• ESM — electronic support measure

• X — X Window System
• CLP — Cell Loss Priority (ATM)
• IMPI — IP (Internet Protocol) Multimedia Private Identity
• VOB — Versioned Object Base
• MNP — Mobile Number Portability
• EC — Enhanced Cellular
• NESC — National Electrical Safety Code
• LMS — Location and Monitoring Service
• AVT — Audio Visual Telecommunications
• LXT — Local Exchange Terminal
• BWX — Broadband Wireless Exchange
• OODBMS — Object-Oriented Database Management Systems
• BSC — Base Station Controller
• MEH — Mobile-Executed Handoff
• AIS-V — Alarm Indication Signal - Virtual
• WFA — Work Force Administration
• INMS — Integrated Network Management System
• IDCU — Integrated Digital Carrier Unit
• LFTYR — Ley Federal de Telecomunicaciones y Radiodifusión
• DCO — Dial Central Office
• AFPS — Automatic Facility Protection Switching
• PSK — Phase Shift Key
• VPC — Virtual Path Connection (ATM)
• PSNEXT — Power Sum Near End Cross Talk
• VCT — Variable Cam Timing
• ULP — Upper Layer Protocol
• GOSIP — Government Open Systems Interconnection Profile
• LIDB — Line Information DataBase
• IXC — interexchange carrier
• NFR — Near-Field Recording
• ADIF — Accounting Data Interchange Format
• N-AMPS — Narrowband Advanced Mobile Phone System
• GSM — Global System for Mobile telecommunications
• ECS — Encryption Control Signal
• BP — Block Parity
• SAR — Segmentation and Reassembly (ATM)
• IBS — In-Building Solutions
• SMSC — Short Message Service Center
• DCC — Digital Control Channel
• PCIA — Personal Communications Industry Association
• VNS — Virtual Network System
• ADM 3X — DS3 Add-Drop Multiplex
• BAOC — Barring of All Outgoing Calls supplementary service
• BDFB — Battery Distribution Feeder Bay
• WIVO — WIreless VelOcity
• AMTI — Airborne Moving Target Indicator
• ZD — Zero Defects
• LCU — Line Control Unit
• TSDU — Transport Service Data Unit
• FEAC — Far End Alarm and Control

• OIM — Operations Interface Module
• TCL — Transverse Conversion Loss
• NPSI — Network Packet Switching Interface
• IPXCP — Internetwork Packet Exchange Control Protocol
• FR — Functional Requirement
• AAL — ATM (Asynchronous Transmission Mode) Adaptive Layer
• JSC — Joint Scientific Committee (ICSU, WCRP, and WMO)
• RNR — Receive Not Ready
• UNO — Universal Network Operations
• MIN — Mobile Identification Number
• NRZ — Nonreturn To Zero
• RTC — Right to Carry
• COP — Character Oriented Protocol
• ACM — Address Complete Message
• EA — expedited acknowledgement
• GLT — Great Lakes Telecom
• VSC — Vertical Service Code
• SSP — Security Service Provider
• QPM — QoS (Quality of Service) Policy Manager
• SAPI — Service Access Point Identifier
• USPI — Universal Serial Phone Interface
• MC/MIC — Mode Common/Mode Indicate Common
• A/D — Analog-to-Digital converter
• LSI — Large-Scale Integration
• HW — Hardware Wars
• ADTM — Asynchronous Data Transfer Mode
• CNID — Calling Number Identification Display
• UTRAN — UMTS (Universal Mobile Telecommunication System) Terrestrial Radio Access Network
• HEC — Header Error Control
• ISSI — Inter-Switching System Interface
• VR — Virtual Router
• RCT — remote Control Terminal
• DMT — Discrete Multi-tone Transmission
• PT — Payload Type (ATM)
• COBE — Corporate Owned Business Only
• CDM — Configuration Data Manager
• TNI — Telephone Network Interface
• ESG — Enhanced Service Gateway
• PGP — Pretty Good Protection (encryption)
• Z — Zulu Time
• BCIX — Berlin Commercial Internet Exchange
• UCM — Use Case Map
• LAT — Local Area Transport (network)
• TSI — time-slot interchange
• VLF — Vertical-Laminar-Flow
• MITS — Metaphors for Integrated Telecommunications Services
• CDPD — Cellular Digital Packet Data
• BASIZE — Buffer Allocation Size
• PNM — Pulse Number Modulation
• VCC — Voice Call Continuity

• FEBE — Far End Block Error (SONET)
• USRT — Universal Synchronous Receiver/Transmitter
• CLI — Calling Line Identification
• MO — Magneto-optic
• XRF — X-Ray Fluorescence
• P&A — Privacy and Authentication
• ANSI — Advanced Network Signaling Input
• DNA — Do Not Answer
• PROV — Provisioning
• HU — Hook Up
• CLF — Carrier Line Failure
• CALA — Customer Address Location Area
• CT — Cordless Telecommunications
• ADM — Administration, Office of
• DSCS — Defense Satellite Communication System
• DLE — Digital Local Exchange
• HDB3 — High-Density Bipolar Three-bit substitution
• SLIC — Subscriber Loop Interface Circuit
• DPT — Dial Pulse Terminate
• DTW — Dynamic Time Warping
• LTU — Line Termination Unit
• ATU-R — ADSL (Asymmetric Digital Subscriber Line) Transceiver Unit - Remote terminal end
• DF — Direction Finding or Finder
• SAMI — Structured Adjustment & Maintenance Interface
• HPN — Home Phone Network
• DAF — Directory Access Function
• FB — Fine Business
• CAE — Common Application Environment
• WNAP — Wireless Network Access Point
• FUD — Fair Use Doctrine
• CDSL — Consumer Digital Subscriber Line
• AI — Adapter Interface
• AARQ — A-Associate Request
• SDN — Software Defined Network
• WRED — Weighted Random Early Detection
• DE — Discard Eligible
• DMNG — Digital Mobile News Gathering
• CD — Committee Draft
• CAN — Controller Area Network
• SS7 — Signaling System 7
• DOD — Dial on Demand
• BSS — Broadband Switching System
• AMOLED — Active Matrix Organic Light-Emitting Diode
• DSU — Digital Service Unit
• QPA — Quality Performance Analysis
• TTC — Telemetry Telecommand and Control
• VCR — Videocassette Recorder
• LZ — Lempel-Ziv compression algorithm
• CWTS — China Wireless Telecommunication Standard
• AAL2 — ATM (Asynchronous Transmission Mode) Adaptation Layer 2

• MOS — Metal Oxide Semiconductor (FET Devices)
• PRI — Priority
• DDM — Data Distribution Manager
• IMTS — Improved Mobile Telephone Service
• BAM — Basic Access Module
• ACMA — Atlantic Cable Maintenance Agreement
• IVN — Interactive Video Network
• EF&I — Engineering, Furnishing and Installation
• DDSN — Digital Derived Services Network
• CLASS — Cell Level ATM (Asynchronous Transfer Mode) Services Simulator
• YIP — Your Internet Phone
• CCH — Common Channel Handler
• LSMS — Local Service Management System
• SBX — Small Business Exchange
• VC — Virtual Circuit (ATM)
• SHR — Self-Healing Ring
• LULT — Line Unit/Line Termination
• ATIS — Automatic Transmitter Identification System
• CFS — Call for Service
• AFCEA — Armed Forces Communications and Electronics Association's
• DMI — Desktop Management Interface (computing)
• FESS — Flywheel Energy Storage System
• TRCSL — Telecommunications Regulatory Commission of Sri Lanka
• MERIS — medium-resolution imaging spectrometer
• ACRE — Authorization and Call Routing Equipment
• PTT — Post Telegraph and Telecommunications
• TLP — Transmission Level Point
• IOC — Interoffice Channel
• TP — Termination Point
• NAM — Number Assignment Module
• TIMS — Telephone Information Management System
• COI — Community of Interest
• CIS — Center for Integrated Systems
• ITU-T — International Telecommunication Union - Telecommunications section
• BONDING — Bandwidth On Demand Interoperability Group
• LVM — Line Verification Module
• OST — Office of Science and Technology
• MNOS — Metal-nitride-oxide Semiconductor
• CSCW — Computer-Supported Cooperative Work
• DCEF — Distributed Cisco Express Forwarding
• ATIS — Alliance for Telecommunications Industry Solutions
• MRCA — Most Recent Common Ancestor
• INWATS — INward Wide Area Telecommunications Service
• SMU — Service Management Unit
• MMS — Multimedia Message Service
• CM — Connection Manager
• BWD — backward
• CEE — Communaut? Economique Europ?enne
• DACS — Digital Access and Cross-Connect System
• MDCP — Media Device Control Protocol

• VFL — Visual Fault Locator
• CD-ROM — Compact Disk-Read-Only Memory
• RBS — Robbed Bit Signaling
• NCOS — Network Class Of Service
• ISD — International Subscriber Dialling
• SCC — Specialized Common Carrier
• WATS — Wide Area Telecommunications Service
• USF — Universal Server Farm
• DACS — Digital Access Carrier System
• BOA — Basic Object Adapter
• ECC — Emergency Communications Center
• TJB — Telephone Junction Box
• TMTC — Telemetry and Telecommand
• NIMH — Nickel-Metal Hydride
• DOV — Data-Over-Voice
• VCA — Voice Connecting Arrangement
• DLT — Digital Line Termination
• CMT — Commercial Metering Transponder
• ASAS — All-Source Analysis System
• CSP — Converged Service Platform
• LRB — Loop Reverse Battery
• WEDE — Wireless Enterprise Delivery Environment
• SNI — Service Node Interface
• AA — Auto-Answer
• MBS — Maximum Burst Size (ATM)
• ECDIS — Electronic Chart Display Information System
• CELP — Code Excited Linear Prediction
• BTN — Billing Telephone Number
• NSN — National Significant Number
• WDSL — Wireless Digital Subscriber Line
• RTFM — Read The Friendly Manual
• ESA — Enhanced Subscriber Authentication
• DORA — EV-DO (EVolution-Data Optimized) standard Revision A
• ACL — Asynchronous Connection-less Link
• OTF — On-The-Fly (data acquisition method)
• CEPT — Conference of European Posts and Telecommunications
• VLR — Visitor Location Register
• AEIMP — Apple Event Interprocess Messaging Protocol
• CD ROM — Compact Disc Read-Only Memory
• WCMP — Wireless Control Message Protocol
• PVN — Private Virtual Network
• DBF — Digital Beam-Forming
• AFRINIC — African Network Information Centre
• NARC — Non-Automatic Relay Center
• ESDS — Electrostatic Discharge Sensitive
• WIM — WAP (Wireless Application Protocol) Identity Module
• TWX — Teletypewriter Exchange (Telex)
• UDT — Unreliable Data Transfer
• SCE — Service Creation Environment
• WPBX — Wireless Private Branch Exchange

• TACSIM — Tactical Simulation (Simulator)
• DOITT — Department of Information Technology and Telecommunications
• DEO — Digital End Office
• NICAD — Nickel Cadmium
• D3 — Digital channel bank, Third generation
• DNA — Digital Network Architecture
• MEECN — Minimum Essential Emergency Communication Network
• O — objective
• SR — Service Request
• INAP — Intelligent Network Application Part
• UMTS — Universal Mobile Telecommunications Standard
• RYP — Russian Yellow Pages
• SHD — Smart Handheld Device
• EKTS — Electronic Key Telephone Set
• NETBIOS — Network Basic Input-Output System
• BFS — Broadcast File System
• FD — Full Duplex
• EGPRS — Enhanced General Packet Radio Service
• JDC — Japan Digital Cellular
• CMAS — Cellular Management System
• TRANS — Transaction
• AIS-P — Alarm Indication Signal - Path
• RLC — Radio Link Control
• WBMP — Wireless Bitmap
• A/C — Air Conditioner
• DMB — Disconnect and Make Busy
• TFL — Telecom Fiji Limited
• CCSS6 — Common Channel Signaling System # 6
• TEM — Transmission Electron Microscope
• FPLMTS — Future Public Land Mobile Telecommunications System
• DBN — Dial-Back Number
• SINS — Ship’s Inertial Navigation System
• RCF — Remote Call Forwarding
• PTN — Public Telephone Network
• SNI — Subscriber Network Interface
• HSCSWD — High-Speed Circuit-SWitched Data
• OCI — object code insertion
• CSL — component sublayer
• ATMS — automatic transmission measuring system
• DS0 — Digital Signal Zero
• APPN — Advanced Peer-to-Peer Network
• MLHG — Multi-Line Hunt Group
• CCITT — Comite Consultatif International Telegraphique et Telephonique (now ITU-T)
• WLAP — Wireless LAN (Local Area Network) Access Point
• MCPC — Multiple Channels Per Carrier
• NMS — NetWare Management System
• CP — Cell Phone
• OID — Object Interaction Diagram
• SCMG — SCCP Management
• SR — Scanning Radiometer

• SPI — Security Parameters Index
• GOS — Gerry Otis Simpson
• DS-1 — Digital Signal, Level 1
• VDSL — VHBR (Very High Bit Rate) Digital Subscriber Line
• MTS — Message Transmission Subsystem
• TARP — Target Identifier Address Resolution Protocol
• TACS — Total Access Cellular System
• CYTA — Cyprus Telecommunications Authority
• LRF — Laser Range Finder
• ADTS — Ameritech Digital Transport Service
• SPT — System Page Table
• AH — Authentication Header
• JMA — Japanese Meteorological Agency
• ASP — Active Signaling Protocol
• AAS — Automatic Announcement Subsystem
• TDRS — Tracking and Data Relay Satellites
• CVT — Circuit Validation Test
• PM — Processable Mode
• APS — Advanced Power System
• ISC — International Switching Center
• SACS — Security Access Control System
• RS — Receive Signature
• ALT — Automatic Link Transfer
• CM — Common Mode
• ACEK — Authentication Encryption Key
• BSVCI — Broadcast Signaling Virtual Channel Identifier
• TRAC — Totally Reconfigurable Analog Circuit
• WDP — Wireless Datagram Protocol
• VGF — Voice Grade Facility
• MQFP — Metric Quad Flat Pack
• WBTS — Wireless Business Telephone System
• SASL — Simple Authentication and Security Layer
• NSDI — National Spatial Data Infrastructure
• MEI — Multiple Extension Interworking
• LMU — Line Monitor Unit
• CPN — Customer Premise Network
• ATB — All Trunks Busy
• XC — Cross-Connect
• CPT — Cellular Paging Teleservice
• LQD — Line Quality Disturbance
• C² — Command and Control
• CS — Connection Segment
• EDGE — Enhanced Data for GSM (Global System for Mobile communication) Evolution
• MODEM — modulation and demodulation
• DDS — Dataphone Digital Service (AT&T)
• QOD — Quality of Data
• NMC — Network Model Coverage
• DAS — Distributed Antenna System
• WDMW — Web Directory for Mobile and Wireless
• CAL — Customer Access Line

• WGX — Wireless Gateway Switch
• DCS — Digital Cross-connect Switch
• LQR — Line Quality Report
• RBT — Ring Back Tone
• BC — Basic Call
• UAN — Universal Area Network
• BUS — Business Units
• WLNP — Wireless Local Number Portability
• WAW — Wide Area Wireless
• WPC — Wireless Personal Communications
• TP — Transaction Processor
• AFIPS — American Federation of Information Processing Societies
• WIPS — Wireless Intelligent Personal Server
• CSP — Continuous Speech Processing
• DME — Distributed Management Environment (OSF)
• RCMAC — Recent Change Memory Administration Center
• XWI — XML (extensible markup language) for Wireless Images
• GOSIP — Government Open System Interconnection Profile
• E — Exchange
• JWG — Joint Working Groupof
• TASI — Time Assigned Speech Interpolation
• DTS — Digital Terminal Systems
• CUG — Closed Users Group
• AEE — Agent Execution Environment
• NANP — North American Numbering Plan
• NF — Not Found
• IRAC — Interdepartment Radio Advisory Committee
• RTU — Right to Use
• LEC — Liquid Encapsulated Czochralski
• BTL — Bell Telephone Laboratories, Inc.
• TPF — Transmission Priority Field
• DLC — Digital Leased Circuit
• PTM — Point-To-Multipoint
• SMAS — Service Management System
• CCS — Common Channel Signaling
• UIF — User Interface Framework
• BPOP — Building Point of Presence
• DTU — Data Terminal Unit
• IDSL — ISDN (Integrated Services Digital Network) Digital Subscriber Line
• TCAM — Telecommunications Access Method
• MTBM — Mean Time Between Maintenances
• CMTS — Cellular Mobile Telephone System
• SVW — Sioux Valley Wireless
• ADC — Advanced Data Control
• SIGTRAN — Signaling Transport
• SVI — Service Interception
• CIPOA — Classical Internet Protocol over ATM (Asynchronous Transfer Mode)
• HCV — High Capacity Voice
• ATACS — Army Tactical Communications System
• CSAA — Central Service Area Authority

• ROSE — Remote Operations Service Element
• ALC — Automatic Line Controller
• FOE — Fiber Optic Equipment
• DORK — Disciples Of The Righteous King
• UIH — Unnumbered Information with Header check
• TWX — Teletypewriter Exchange Service
• MMJ — Modified Modular Jack
• MAC — Message Authenticity Check
• CPCI — Compact Peripheral Component Interconnect
• DSX — Digital Signal Cross-Connect
• EADAS — Engineering and Administrative Data Acquisition System
• DACS — Digital Access Cross-Connect Switch
• PPV — Pay-Per-View
• SOR — Statement of Requirements
• APTG — Asia Pacific Telecom Group
• 4G — Fourth Generation
• ASA — Avaya Site Administration
• 800 — Freephone
• WUP — Wired Up Privacy
• CU — Cooling Unit
• O/G — Outgoing
• NEF — Network Element Function
• IDD — International Direct Dialing
• GSM-R — Global System for Mobile (communications) – Rail
• RANAP — Radio Access Network Application Part
• MP — Master Processor
• MOD — Modulo
• TAE — Terminal Adapter Equipment
• AMP — amplifier / amplification
• WBOK — Wireless Broadband of Oklahoma
• SS6 — Signalling System 6
• ABR — Available Bandwidth Rate
• ITFS — International Toll Free Services
• APR — Alarm Processing Remote
• IOS — Internet Over Satellite
• D4 — Digital channel bank, Fourth generation
• GTXC — Global Telephone Exchange Carrier
• TLC — Television the Learning Channel
• DCP — Distributed Collaborative Planning
• SIO — Service Information Octet
• GEO — Geostationary Earth Orbit
• SCRC — SCCP Routing Control
• DPDCH — Dedicated Physical Data Channel
• ICLD — Inter-Channel Level Difference
• CSLIP — Compressed SLIP
• DISA — Direct Inward Switch Access
• ACA — Automatic Circuit Assurance
• CLIP — Caller Line Identification Presentation
• QEDI — Quod Erat Demonstrandum
• HUMAN — High-speed Unlicensed Metropolitan Area Network

• DRTL — Dial Repeating Tie Line
• ADAD — Automatic Dialing Announcing Device
• ISDP — Intelligent Shared Dual Path
• UPC — Usage Parameter Control
• SMDS — Switched Multi-megabit Data Service
• ARS — Automatic Route Selection
• CCC — Credit Card Calling
• CAP — Competitive Access Provider
• CCC — CDMA Cluster Controller
• COMPANDER — COMpressor/exPANDER
• TSGR — Transport System Generic Requirements
• ISP — International Signaling Point
• TAPI — Telephony Application Programming Interface
• TX — Transmit
• DSP — Data Service Provider