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Computing & IT >> Telecom Abbreviations

Look through 4999 acronyms and abbreviations related to Telecom:

• IPB — Invision Power Board
• XFMR — Transformer
• DDRS — Dynamic Data Rate Selection
• CBCU — Centralized Broadband Control Unit
• DCE — Data Circuit-terminating Equipment
• DWDM — Dense Wavelength Division Multiplexing
• DOE — Distributed Object Environment
• SYN — Synchronous
• ECG — Electrocardiogram
• EBITDA — Earnings before Interest, Taxes, Depreciation and Amortization
• CT — Computed Tomography
• LAN — Local Area Network
• CSR — Customer Service Representative
• GFSK — Gaussian Frequency Shift Keying
• CONG — Congestion message
• ETA — Estimated Time of Arrival
• APR — Annual Percentage Rate
• CSMA/CA — Carrier Sense Multiple Access/Collision Avoidance
• IQ — Intelligence Quotient
• CSMA/CD — Carrier Sense Multiple Access with Collision Detection
• CSMA — Carrier Sense Multiple Access
• CSMA/CD — Carrier sense multiple access / collision detection
• DAM — Diagnostic Acceptability Measure
• ISAR — Inverse Synthetic-Aperture Radar
• D-H — Diffie-Hellman
• DWDM — Dense Wavelength-Division Multiplexing
• MLS — Microwave Landing System
• YMMV — Your Mileage May Vary
• ADM — Add-Drop Multiplexer
• YTD — Year To Date
• FTP — File Transfer Protocol
• FDIC — Federal Deposit Insurance Corporation
• BRDF — Bidirectional Reflectance Distribution Function
• ISO — In Search Of
• OIC — Oh I See
• MAN — Metropolitan Area Network
• ROM — Read-Only Memory
• ASAP — As Soon As Possible (pronounced AY-sap)
• LASER — Light Amplification By Stimulated Emission Of Radiation (cf. Maser)
• AUP — Acceptable Use Policy
• ECU — Electronic Control Unit
• TEMIP — Telecommunications Management Information Platform
• TNYWR — The Number You Will Receive
• IT — Information Technology
• CPE — Customer Premises Equipment
• DAC — Discretionary Access Control
• CPU — Central Processing Unit
• F2F — Face To Face (also Meeting In Person)
• XML — Extensible Markup Language
• IAMAI — Internet and Mobile Association of India

• WWW — World Wide Web
• BVR — Beyond Visual Range
• LED — Light-Emitting Diode
• IRC — Internet Relay Chat
• DSCP — Differentiated Services Control Point
• CUG — Closed User Group
• RFQ — Request For Quotation
• DND — Do Not Disturb
• UK — United Kingdom of Great Britain and Northern Ireland
• ANSI — American National Standards Institute, Inc.
• CDR — Critical Design Review
• DBORS — Data Base of Records
• CSA — Canadian Space Agency
• WTG — Way To Go
• CCM — counter-countermeasure
• VIP — Very Important Person
• RDF — Resource Description Framework
• BTW — By The Way
• BIP — Bit-Interleaved Parity
• ACC — Adaptive Cruise Control
• MBR — Master Boot Record
• CCSDS — Consultative/Consultative Committee for Space Data Systems
• BBS — Bulletin Board Service
• SAR — Search And Rescue
• FEMA — Federal Emergency Management Agency
• ISO — International Organization for Standardization
• ACK — ACKnowledgment
• QC — Quality Control
• UDP — User Datagram Protocol (FDDI related)
• OEM — Original Equipment Manufacturer (usually in reference to car parts)
• AFAIK — As Far As I Know
• EAP — Employee Assistance Program
• DFD — Displaced Frame Difference
• ATOM — Any Transport over MPLS (Multi-Protocol Label Switching)
• AATSR — Advanced Along-Track Scanning Radiometer
• ESA — European Space Agency
• DBMS — Database Management System
• LCD — Liquid Crystal Display
• WML — Wireless Markup Language
• ABI — Application Binary Interface
• PDR — Preliminary Design Review
• BUR — Bandwidth Usage Redundancy
• CCB — Change Control Board
• LRJ — Location Reject
• EDI — Electronic Data Interchange
• IRL — In Real Life
• WDM — Wavelength Division Multiplexing (fiber optics)
• FET — Field Effect Transistor
• AC — Alternating Current
• ATM — Automatic Teller Machine

• C4I — Command, Control, Communications, Computers, & Intelligence
• NOS — Network Operating System
• WWW3 — World Wide Web Consortium
• CD — Compact Disc
• CY — Calendar Year
• QFSK — Quadrature Frequency Shift Keying
• ACE — Access Control Entry
• RF — Radio Frequency
• GSM — Global System for Mobile Communications
• LRU — Line Replaceable Unit
• RPI — Retail Price Index
• DSC — Differential Scanning Calorimetry
• RWR — Radar Warning Receiver
• ACH — Automated Clearing House
• FAR — Federal Aviation Regulation
• MB — Megabyte
• VM — Voice Mail
• CV — Curriculum Vitae
• IRR — Internal Rate of Return
• MMS — Multimedia Messaging Service
• ATTN — Attention
• CS — Computer Science
• CAUCE — Coalition Against Unsolicited Commercial Email
• NFS — Network File System
• DDD — Direct Distance Dial
• ASA — American Standards Association
• PDH — Plesiochronous Digital Hierarchy
• GATT — General Agreement on Tariffs and Trade (government)
• EIS — Executive Information System
• ISP — Internet Service Provider
• ALC — Automatic Level Control
• COB — close of business (End of duty day)
• DSA — Digital Signature Algorithm
• 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.
• Y2K — Year 2000
• SMTP — Simple Mail Transfer Protocol
• IP — Internet Protocol
• STS — Space Transportation System
• AES — Advanced Encryption Standard
• CGI — Common Gateway Interface
• EOM — End Of Message
• PDA — Personal Digital Assistant
• BPM — Beats Per Minute
• APT — Automatic Picture Transmission
• ADD — Addendum
• HTTP — Hypertext Transfer Protocol
• SDMA — Space Division Multiple Access
• ATA — Area Transportation Authority
• POC — Point Of Contact
• AAC — Advanced Audio Coding

• EFF — Electronic Frontier Foundation
• CEO — Chief Executive Officer
• NMSE — Normalized Mean Square Error
• GIS — Geographic Information System
• TQM — Total Quality Management
• ACD — Automatic Call Distributor
• CCIS — Common Channel Interoffice Signaling
• LLC — Limited Liability Company
• RFP — Request For Proposal
• ADM — Add/Drop Multiplexer
• DMSP — Defense Meteorological Satellite Program (U.S.)
• ADR — Address
• R&D — Research & Development
• AES — Auger Electron Spectroscopy
• VAT — Value Added Tax
• ATM — Asynchronous Transfer Mode
• COR — Carrier Operated Relay
• AME — Amplitude Modulation Equivalent
• SCSI — Small Computer System Interface
• DME — Distance Measuring Equipment
• MST — Mountain Standard Time
• MOU — Memorandum of Understanding (an MOU between Food & Drug Administratin and a regulatory agency in another country allows mutual recognition of inspections)
• ASME — American Society of Mechanical Engineers
• DDL — Data Definition Language
• EW — Electronic Warfare
• RNC — Radio Network Controller
• WAN — Wide Area Network
• GPRS — General Packet Radio Service
• CR — Carriage Return
• NIC — Network Interface Card
• QI — Quality Improvement
• AC — Access Control
• SAN — Storage Area Network
• ABR — Available Bit Rate
• BECN — Backward Explicit Congestion Notification
• PDT — Pacific Daylight Time
• UAV — Unmanned Aerial Vehicle
• TCB — Trusted Computing Base
• RFC — Request For Comment
• CAE — Computer-Aided Engineering
• PUHU — Pick Up Hang Up
• THX — Thanks
• PPM — parts per million
• VVX — Voice and Video eXchange
• MRI — Magnetic Resonance Imaging
• NPI — New Product Introduction
• WBS — Work Breakdown Structure
• ASK — amplitude shift keying
• SRAM — Static Random Access Memory (ess-ram)
• AVHRR — Advanced Very High Resolution Radiometer  

• PDF — Portable Document Format (created by Adobe Acrobat)
• ASR — Airport Surveillance Radar
• SP — Service Provider
• WWW — World Weather Watch
• S X S — Step-by-Step
• VR — Virtual Reality
• CDR — Call-Detail Record
• AIR — Account Information and Refill
• DB — Decibel
• ATF — Advanced Tactical Fighter
• EST — Eastern Standard Time
• PCB — printed circuit board
• CBC — cipher block chaining
• IPO — Initial Public Offering
• RPC — Remote Procedure Call
• DTX — Discontinuous Transmission
• RU — Are You?
• CIR — Committed Information Rate (Frame Relay)
• TCP — Transmission Control Protocol
• APIC — Advanced Programmable Interrupt Controller
• ABC — activity based costing
• FAA — Federal Aviation Administration
• SCC — Standards Council of Canada
• DFS — Distributed File System
• EC — European Commission
• AD — Active Directory
• WEP — Wired Equivalent Privacy
• CPT — Carriage Paid To
• BTU — British Thermal Unit
• AM — Ante Meridian
• 100BASE-T2 — 100 Megabits per Second, Baseband, Two-pair Category 3 UTP cables
• CU — Control Unit
• TC — Telephone Call
• AIS — Automated Information System
• ATCRBS — Air Traffic Control Radar Beacon System
• DMX — De-MultipleXer
• ACFQ — Absence Compensation Fair Queuing
• AP — Application Protocol
• API — Application Programming Interface
• CB — Call Back
• SD — Standard Deviation
• CFE — Contractor-Furnished Equipment
• JAXA — Japan Aerospace Exploration Agency
• CIO — Chief Information Officer
• SLA — Service Level Agreement
• ARPA — Advanced Research Projects Agency (made early internet)
• DMTS — Distinguished Member Of Technical Staff
• IM — Instant Message
• RDY — Ready
• DTE — Data Terminal Equipment

• CIM — Corporate Information Management
• AOA — Angle Of Arrival
• ASTM — American Society for Testing and Materials (Philadelphia, Pennsylvania)
• ATM — Adobe Type Manager
• CMI — Computer Managed Instruction
• WB — Welcome Back
• BS — Base Station
• EMG — Electromyogram
• BRB — Be right back
• RDBMS — Relational Database Management System
• SIG — Special Interest Group
• DHCP — Dynamic Host Configuration Protocol
• TAC — Technical Assistance Center
• NMT — Nordic Mobile Telephone
• CAM — Computer-Aided Mapping
• DES — Data Encryption Standard
• CPM — Critical Path Method
• DOA — dead on arrival
• UPS — Ultraviolet Photoelectron Spectroscopy
• FX — Foreign Exchange
• I/O — Input/Output
• JV — Joint Venture
• ISO — Infrared Space Observatory
• CIS — Commonwealth of Independent States
• AM — Amplitude Modulation
• SQA — Software Quality Assurance
• PLMN — Public Land Mobile Network
• SLIP — Serial Line Interface Protocol
• RM — Resource Management
• GRE — Generic Routing Encapsulation
• MDA — Monochrome Display Adapter
• CM — Configuration Management
• ATS — applications technology satellite
• NIH — Not Invented Here
• MTBF — Mean Time Before Failure
• Q&A — Question & Answer
• RAEX — Roaming Agreement EXchange
• ACL — Access Control List
• MIC — Message Integrity Check
• QMS — Quality Management System
• S-BCCH — Short Message Service Broadcast Control Channel
• UAS — Unavailable Seconds
• MAC — Message Authentication Code
• EBCDIC — Extended Binary Coded Decimal Interchange Code (pronounced Eb-see-dik) (cf. BCD)
• X-BAR — Crossbar telephone exchange
• BBU — Baseband Unit
• MSN — Microsoft Network
• NATO — North Atlantic Treaty Organisation
• DIT — Directory Information Tree
• IMPACT — Integrated Manufacturing Precision Assembly Cellular Technology

• VDS — Variable Depth Sonar
• MOS — Model Output Statistics
• ISRO — Indian Space Research Organisation
• A-KEY — Authentication key
• SME — Subject Matter Expert
• LCP — Link Control Protocol
• CRL — Certificate Revocation List
• ASCII — American National Standard Code for Information Interchange
• MOB — Mobile
• DSA — Directory System Agent
• EPA — Environmental Protection Agency (US)
• QOS — Quality of Service
• CC — Carbon Copy
• TPDU — Transport Protocol Data Unit
• TM — Technical Manual
• FCW — Federal Computer Week
• M — Meter
• TNSTAAFL — There's No Such Thing As A Free Lunch
• AT — Access Tandem
• CC — Call Control
• B-ICI — Broadband Inter-Carrier Interface
• MS — Message Store
• ME — Mobile Equipment
• UHF — Ultra High Frequency (300-3000 MHz; 1m-10cm)
• EAP — Extensible Authentication Protocol
• PLD — Programmable Logic Device
• GUI — Graphical User Interface (goo-ey)
• OSS — Operational Support System
• PAR — Precision Approach Radar
• USB — Universal Serial Bus
• MS — Mobile Station
• TV — Television
• ADSL — Asymmetric Digital Subscriber Line
• ICT — Information and Communication Technology
• GPS — Global Positioning System (ex-NAVSTAR)
• CDS — Cell Directory Service
• BPRZ — Bipolar Return-to-Zero
• FFT — Fast Fourier Transform
• AGP — Accelerated Graphics Port
• SDR — Special Drawing Rights
• SGML — Standard Generalized Markup Language
• VIRUS — Vital Information Resources Under Siege
• AF — Audio Frequency
• FIFO — First In, First Out
• DT — DWDM (Dense Wavelength Division Multiplexing) Terminal
• SMS — Short Message Service
• TS — Technical Specification
• TTYL — Talk To You Later (Internet Slang)
• YP — Yellow Pages
• ATC — Air traffic control

• HDLC — High-Level Data Link Control
• AML — Amplitude Modulated Link
• RACON — Radar Beacon
• ADPE — Automatic Data Processing Equipment
• EGA — Enhanced Graphics Adapter
• CBDS — Connectionless Broadband Data Service
• RCU — Remote Control Unit
• BCC — Blind Carbon Copy
• TBD — To Be Decided
• OMG — Object Management Group
• MPI — Message Passing Interface
• JIS — Japanese Industrial Standard
• DNS — Domain Name System
• PO — Purchase Order
• EDS — Electronic Data Systems Corporation
• IS — Intermediate System
• DLC — Digital Loop Carrier
• FC — Fibre Channel
• IW — Information Warfare
• SAS — Statistical Analysis System
• VTC — Video Teleconference
• VM — Virtual Machine
• COMJAM — Communications Jamming
• DARPA — Defense Advanced Research Projects Agency (US)
• AT — Advanced Technology
• LLC — Logical Link Control
• Z — Zero
• CERT — Computer Emergency Response Team
• PAL — Programmable Array Logic
• URL — Universal Resource Locator
• RCC — Rescue Coordination Center
• VHF — Very High Frequency
• X-ON — Transmitter On
• CS — Cable Select
• MF — Medium Frequency
• RAM — random-access memory
• B3ZS — bipolar 3-zero substitution
• PNG — Portable Network Graphics (graphic file standard/extension)
• LCN — Logical Channel Number
• WMAN — Wireless Metropolitan Area Network
• ICMP — Internet Control Message Protocol
• UAN — Universal Access Number
• SA — Scientific American
• SEM — Space Environment Monitor
• DC — Direct Current
• DLR — Design Layout Record
• SDD — Software Design Document
• MHS — Microwave Humidity Sounder
• ACM — Association for Computing Machinery
• EU — European Union (1994; formerly referred to as the EEC or EC)

• CLNP — ConnectionLess-mode Network Protocol
• EVP — Executive Vice President
• BSD — Berkeley Software Distribution
• PSK — phase-shift keying
• PM — Preventive Maintenance
• X-OFF — Transmitter Off
• ISS — International Space Station
• ARPU — Average Revenue Per User
• SSM — Source-Specific Multicast
• AE — Application Entity
• LEO — Low Earth Orbit (satellite communications)
• CIC — Circuit Identification Code
• HW — Hardware
• AR — Access Rate
• DIS — Distributed Interactive Simulation
• IDT — Integrated Digital Terminal
• F — Fellow
• AGC — Automatic Gain Control
• ECN — Explicit Congestion Notification
• RAD — Rapid Application Development
• LSR — Local Service Request
• ABET — Accreditation Board for Engineering and Technology, Inc.
• DPC — Destination Point Code
• RIP — Routing Information Protocol
• CIM — Common Information Model
• QAM — quadrature amplitude modulation
• ADT — Abstract Data Type
• ACE — Advanced Computing Environment
• MS — Management System
• AE — Account Executive
• VOP — Voice Over Packet
• LF — Low Frequency
• CABS — Carrier Access Billing System
• SEC — Software Engineering Center
• CCTV — Closed-circuit television
• NI — Network Interface
• IVR — Interactive Voice Response (telephone technology)
• DCE — Distributed Computing Environment
• TBD — To Be Determined
• OTN — Optical Transport Network
• TLS — Transport Layer Security
• YGWYPF — You Get What You Pay For
• VB — Visual Basic
• NPV — Net Present Value {economics}
• ARPANET — ARPA Network
• H323 — ANSI standard for format over IP
• CEV — Controlled Environment Vault
• UR — Your
• MC — Message Center
• RFI — Radio Frequency Interference

• NSF — National Sanitation Foundation
• XA-FR — Exchange Access Frame Relay
• SWAG — Scientific Wild Ass Guess
• CAC — Carrier Access Code
• FXO — Foreign Exchange Office
• WS — Workstation
• E — Energy
• CUL — See You Later
• ACK — Acknowledge (telecommunications; Cf. NAK)
• DQPSK — Differential Quadrature Phase-Shift Keying
• AMI — Alternate Mark Inversion
• EAS — Extended Area Service
• CW — Continuous Wave
• NSA — National Security Agency
• OSPF — Open Shortest Path First (ATM)
• ASR — Access Service Request
• BBS — Bulletin Board System
• P&L — Profit and Loss statement
• MSE — Mobile Subscriber Equipment
• CO — Certificate of Origin
• EEPROM — Electrically Erasable Programmable Read-Only Memory
• ADF — Automatic Direction Finder
• WACN ID — Wide Area Communications Network IDentifier
• CHAP — Challenge Handshake Authentication Protocol (ATM)
• DOM — Document Object Model
• TOS — Type Of Service
• AS — Autonomous System
• IPX — Internetwork Packet Exchange
• RTS — Request To Send
• SEI — Software Engineering Institute
• DRAM — Dynamic Random Access Memory (dee-ram) (computing)
• NYSE — New York Stock Exchange
• OBO — Or Best Offer
• SPI — Service Provider Interface
• OSI — Open Systems Interconnection (iso Standard)
• FA — Functional Area
• COM — Component Object Model
• BCD — Binary-Coded Decimal
• C-NBAP — Common Node B Application Part
• IETF — Internet Engineering Task Force
• PDN — Public Data Network
• TEC — Total Electron Content
• SM — Senior Member
• HSD — High Speed Data
• AMT — Amount
• PVT — Private
• PE — Polyethylene
• SVC — Scalable Video Coding
• MS — Millisecond
• IP — Intelligent Peripheral

• FDDI — Fiber Distributed Data Interface
• AFC — Automatic Frequency Control
• RT — Remote Terminal
• HSDPA — High-Speed Downlink Packet Access
• DSSS — Direct Sequence Spread Spectrum
• D-NBAP — Dedicated Node B Application Part
• ZDBOP — Ziff-Davis Benchmark Operation
• DTR — Data Terminal Ready
• NEC — National Electrical Code
• MP — Multilink Protocol
• ERT — Emergency Response Team
• DS — Digital Signal
• VOD — Video On Demand
• SIL — Speech Interference Level
• CGI — Computer-Generated Imagery
• RFS — Request For Service
• URI — Uniform Resource Identifier
• AFP — AppleTalk Filing Protocol
• ECT — Explicit Call Transfer
• WPS — Wireless Priority Service
• SCP — Service Control Point
• CRT — Cathode Ray Tube (type of TV)
• ATSR — Along-Track Scanning Radiometer
• OM — Old Man
• COO — Cost of Ownership
• AU — Audio Unit
• BACP — Bandwidth Allocation Control Protocol
• BT — British Telecommunications
• UA — User Agent
• ZIP — Zone Improvement Plan
• HF — High Frequency
• RDP — Radar Data Processing
• PWD — Password
• BRA — Basic Rate Access
• NAS — Network Access Server
• MD — Mediation Device
• PECVD — Plasma-Enhanced Chemical Vapor Deposition
• TB — Terabyte
• STI — Speech Transmission Index
• NTFS — New Technology File System
• ZIP — Zone Information Protocol
• NOTAM — Notice to Airmen
• DQE — Detective Quantum Efficiency
• PSTN — Public Switched Telephone Network
• MSR — Microwave Scanning Radiometer
• IS — International Standard
• MSU — Microwave Sounding Unit
• JSC — Johnson Space Center (Houston, TX)
• IN — Intelligent Network
• DA — Destination Address

• UAX 14 — Unit Automatic eXchange type 14
• PRF — Pulse Repetition Frequency
• CA — Certificate Authority
• DMARC — Demarcation point
• APC — American Power Conversion
• LF — Line Feed
• PGP — Pretty Good Privacy (encryption)
• EEC — European Economic Community (predecessor of the European Union|EU)
• TN — Telephone Number
• NLMS — Normalized Least Mean Square
• ARP — Address Resolution Protocol (ATM)
• CIA — Central Intelligence Agency
• DOD — United States Department of Defense
• CATV — Community Antenna Television
• FCA — Free Carrier
• NA — Not Applicable
• CAM — computer aided manufacturing
• PMA — Physical Medium Attachment
• PT — Project Team
• OMS — Optical Multiplex Section
• AMI — Advanced Metering Infrastructure
• E-LEAD — Ear Lead
• NIC — Network Information Center
• CT — Computer Telephony
• CAB — Conformity Assessment Body
• ISI — Inter-Symbol Interference
• DCP — Design Change Package
• STK — Satellite Tool Kit
• WB — Write Back
• ACR — Attenuation Crosstalk Ratio
• CU — See You
• 3G — Third Generation mobile phone network
• CBT — Computer Based Training
• NIS — Network Information Service
• RCV — Receive
• MIS — Management Information System (OSHA)
• VLL — Virtual Leased Line
• NESDIS — National Environmental Satellite, Data, and Information Service
• QA — Center for Quality Assurance in International Education
• CAN — Campus Area Network
• OCR — Optical Character Recognition
• PCI — Peripheral Component Interconnect
• STP — Spanning Tree Protocol
• BER — Bit-Error Rate
• BST — British Summer Time
• UL — Uplink
• COO — Chief Operation Officer
• EPR — Electron Paramagnetic Resonance
• M — Management
• BT — BlueTooth

• RA — Risk Analysis
• MDA — Model Driven Architecture
• WG — Working Group
• ADEOS — ADvanced Earth Observing Satellite (Japan)
• RFI — Request For Information. Sales department shorthand. Special priority when use in conjunction with RFN (see below).
• AFS — Andrew File System
• DUP — Duplicate
• MCU — Multipoint Control Unit
• RH — Relative Humidity
• FAQ — Frequently Asked Questions (sometimes Pronounced Fak)
• TRM — Technical Reference Model
• COQ — Cost Of Quality
• SCTP — Stream Control Transmission Protocol
• AFSK — Audio Frequency Shift Keying
• BIP — Band Interleaved by Pixel
• CAD — Computer Aided Designer
• AXE 10 — Series of electronic telephone exchanges from L.M. Ericsson
• SVC — Switched Virtual Connection
• GDS — Global Distribution System
• SVD — Singular Value Decomposition
• TOP — Technical Office Protocol
• AMLCD — Active Matrix Liquid Crystal Display
• TE — Traffic Engineering
• DAP — Directory Access Protocol
• RM — Regional Manager
• IIS — Internet Information Services
• DSS — Decision Support System
• MLS — Multiple Listing Service
• ISA — Industry Standard Architecture
• FR — Frame Relay
• SAN — System Area Network
• LZ — Landing Zone
• SBC — Session Border Controller
• MHS — Message Handling System (electronic)
• MVS — Multiple Virtual Storage
• SPADATS — Space Detection And Tracking System
• EDVAC — Electronic Discrete Variable Automatic Computer
• EAC — Engineering Accreditation Commission
• ISDN — Integrated Services Digital Network
• DOJ — Department of Justice (US)
• JPL — Jet Propulsion Laboratory (California Institute of Technology) (NASA)
• AMD — Advanced Micro Devices, Inc. (producer of computer chips)
• TCP/IP — transmission control protocol/internet protocol
• PAN — Personal Area Network
• BIS — Bureau of Indian Standards
• STM — Short Term Memory
• VAC — Vacant
• GB — Gigabyte
• RFO — Reason For Outage
• ES — Errored Second

• LP — Low Pressure
• OPC — Originating Point Code
• LD — Long Distance
• NMS — Network Management System
• W3C — World Wide Web Consortium
• TG — Task Group
• MOL — Manned Orbiting Laboratory
• AAAS — American Association for the Advancement of Science
• DID — Digital Information Display
• PGA — Programmable Gate Array
• FE — Far End
• AM — Activity Manager
• ARC — Army Reuse Center
• AIS — Alarm Indication Signal
• CDMA — Code Division Multiple Access (voice/data transmission)
• CNM — Customer Network Management
• DAL — Dedicated Access Line
• USD — United States Dollar
• CTS — Clear To Send
• SPC — Stored Program Control
• ENIAC — Electronic Numerical Integrator And Computer
• PPB — parts per billion (109)
• VOL — Volume
• ASR — Automatic Speech Recognition
• SCN — Switched Circuit Network
• PSD — Phase-Sensitive Detector
• NCS — National Communications System
• DVP — Digital Voice Privacy
• MRC — Monthly Recurring Charge
• TWT — Traveling Wave Tube
• BS — Beam Splitter
• PDS — Protected Distribution System
• OAS — Organization of American States
• RAID — Redundant Array of Inexpensive Disks
• EPABX — Electronic Private Automatic Branch Exchange
• CAA — Civil Aviation Authority
• IEC — International Electrotechnical Commission
• Y — Yttrium
• MTTR — Mean Time To Repair
• CF — Compact Flash
• VPN — Virtual Private Network (ATM)
• I.LINK — IEEE 1394, High Performance Serial Bus, implementation
• 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.
• PDU — Protocol data unit (such as segment, packet, frame, etc.)
• LPC — Linear Predictive Coding
• BR — Branch
• FITS — Flexible Image Transport System
• SQL — Structured Query Language
• CSAT — Customer Satisfaction
• Y — Yes

• DX — Duplex
• AEW — Airborne Early Warning
• OC — Optical Carrier
• BG — Background
• MOD — Modify
• ESS — Electronic Switching System
• CG — Coast Guard
• TLC — The Learning Channel
• SL — Single Line
• CAV — Constant Angular Velocity
• RT — Response Time
• ITSEC — Information Technology Security Evaluation Criteria
• VT — Vacuum Tube
• P — Predicted
• DC — Display Controller
• SBC — Southwestern Bell Corporation
• DMA — direct memory access (computer term)
• DOS — Disk Operating System
• AEC — Architecture, Engineering, Construction
• CB — Common Battery
• IS — Information System
• NNM — Network Node Manager
• ATA — Analog Telephone Adapter
• AADC — Automated Area Distribution Center
• CS — Convergence Sublayer (ATM)
• DC — Disconnected
• LEN — Line Equipment Number
• DEC — Decimal
• 1000BASE-T — 1000 Megabits per Second, Baseband, Twisted Pair
• METRO — Metropolitan
• RACF — Resource Access Control Facility
• PS — Product Specification
• PIN — Personal Identification Number
• RSRQ — Reference Signal Received Quality
• ARA — Apple Remote Access
• SF — Single Frequency
• AAS — Adaptive Antenna System
• FUP — Fair Use Policy
• SOW — Statement Of Work
• EX — Exercise
• DASD — Direct Access Storage Device
• FCP — Fibre Channel Protocol
• ECO — Engineering Change Order
• MCSD — Microsoft Certified Solution Developer
• BPR — Business Process Re-engineering
• PD — Public Domain
• LPE — Liquid Phase Epitaxy
• TSR — Telecommunications Service Request
• DCS — Digital Cross-connect System
• STP — Signal Transfer Point

• SNMP — Simple Network Management Protocol (ATM)
• T-CARRIER — Trunk Carrier
• AOI — Area Of Interest
• POP — Point Of Presence (Internet)
• ASQC — American Society for Quality Control's
• OS — Operating System
• PC — Personal computer (host)
• LEP — Large Electron Positron
• WYSIWYG — What You See Is What You Get (pronounced Wizzy-wig. See Entry For Derived Acronyms)
• ECAC — European Civil Aviation Conference
• DCN — Disconnect
• ARG — Argument
• TI — Time Interval
• SOHO — Small Office Home Office
• BSOD — Blue Screen Of Death
• EIP — Equipment installation procedure
• ECP — Encryption Control Protocol
• TE — Test Equipment
• ETS — European Telecommunication Standard
• CBP — Coded Block Pattern
• CATV — Cable Television
• ELINT — Electronic Intelligence Satellite
• PUB — Publication (file name extension)
• SAS — Special Access Surcharge
• VC — Virtual Channel
• FDL — Facility Data Link
• PE — Probable Error
• CAM — Content Addressable Memory
• DCOM — Distributed Component Object Model
• PDS — Planetary Data System
• AIN — Advanced Intelligent Network
• BERT — Bit Error Rate Tester (telecommunication)
• O&M — Operation and Maintenance
• OLAP — Online Analytical Processing
• CER — Cell Error Ratio
• AQL — Acceptable Quality Level
• BOC — Bell Operating Company
• AAAI — American Association for Artificial Intelligence's
• APM — Advanced Power Management
• ATN — Aeronautical Telecommunication Network
• SNR — Signal-to-Noise Ratio
• BYOD — Bring Your Own Device
• SAIC — Science Applications International Corporation
• EFS — Encrypting File System
• FCS — Frame check sequence (Ethernet)
• M-CSI — Mobility management CAMEL (Customized Applications for Mobile network Enhanced Logic) Subscription Information
• RPM — Revolutions Per Minute, (Rotations Per Minute)
• BTC — Botswana Telecommunications Corporation
• DUC — Digital Up-Converter
• DAHDI — Digium/Asterisk Hardware Device Interface

• PTA — Pakistan Telecommunication Authority
• ADC — Analog-Digital Converter
• DDS — Digital Data Service
• A — Anode
• UP — User Profile
• ACT — Activity
• LED — law enforcement desk; light emitting diode
• CTD — Cumulative Trauma Disorder
• DBS — Direct Broadcast Satellite
• MCA — Micro Channel Architecture
• DSL — Digital Subscriber Line
• SHF — Super High Frequency
• CIS — CompuServe Information Service
• SAR — Specific Absorption Rate
• BGP — Border Gateway Protocol (routing protocol)
• RJ-25 — Registered Jack type 25 (6-wire connector)
• PERT — Program Evaluation and Review Technique
• ROI — Return on Investment
• FE — Finite Element
• E — Echo
• DSTE — Digital Subscriber Terminal Equipment
• DL — Digital Library
• YL — Young Lady
• AMHS — Automated Message Handling System
• CU — Channel Unit
• AUD — Audit
• MCD — Magnetic Circular Dichroism
• BNSC — British National Space Centre
• AS — Access System
• SD — Software Development
• ERP — Enterprise Resource Planning
• IT — Integration Test
• CDC — Connected Device Configuration
• SLP — Service Location Protocol
• DCS — Digital Cellular System
• CCTA — Central Computer and Telecommunications Agency
• IRS — U.S. Internal Revenue Service
• VLF — Very Low Frequency
• SML — Service Management Layer
• AAF — Advanced Authoring Format
• DDE — Dynamic Data Exchange (in software parlance)
• ITU — International Telecommunication Union
• KISS — Keep It Simple Stupid
• CMT — Cadmium Mercury Telluride
• 10BASE-T — 10 Megabits per second, Baseband, Twisted pair
• MAC — Media Access Control
• LU — Logical Unit
• ROFL — Rolling on the floor laughing
• SSL — Secure Socket Layer
• DCS — Digital Cross-Connect

• AT&T — American Telephone & Telegraph
• OTS — Optical Transmission Section
• ASIC — application-specific integration circuit
• PRI — Primary Rate Interface (ISDN)
• FAA — Federal Aviation Agency
• TE — Terminal Equipment
• CRM — Customer Relationship Management
• PPP — Point-to-Point Protocol
• EOT — End Of Transmission
• NA — Network Adapter
• Q — Quadrature
• NOAA — National Oceanic and Atmospheric Administration (US)
• RFD — Request For Discussion
• RT — Radiotelephone
• ADN — Advanced Digital Network
• BS — Broadcast Satellite
• NIST — National Institute of Standards and Technology
• 9 — Nine
• ROSAT — Roentgen Satellite
• ECPA — Electronic Communications Privacy Act 1986
• CO — Central Office
• ACO — Additional Call Offering
• TNX — Thanks
• TCM — Trellis-Coded Modulation
• FIPS — Federal Information Processing Standard
• CDT — Central Daylight Time
• DLL — Dynamic Link Library (computer file)
• RTN — Regional Telecommunication Network
• HZ — cycles per second (hertz)
• MTSO — Mobile Telephone Switching Office
• JVM — Java Virtual Machine
• TSB — Telecommunication Standardization Bureau
• LT — Less Than
• EMR — Electromagnetic Radiation
• NIC — Network Interface Controller
• BPS — bits per second
• EMEA — Europe, Middle East and Africa
• IV — Initialization Vector
• ACE — Adaptive Communication Environment
• HTTPS — HyperText Transfer Protocol Secure
• RARP — Reverse Address Resolution Protocol
• OAM&P — Operations, Administration, Maintenance & Provisioning
• GSA — U.S. General Services Administration
• NRC — National Research Council (Canada)
• TCSEC — Trusted Computer System Evaluation Criteria
• ASARS — Advanced Synthetic Aperture Radar System
• ADCCP — Advanced Data Communications Control Procedures
• TO — Technical Order
• ELF — Extremely Low Frequency
• GOS — Grade Of Service

• CMM — Capability Maturity Model
• ADL — Advanced Distributed Learning
• EECM — End-to-End Call Manager
• T-IC — T-interConnect
• PDC — Personal Digital Cellular
• WWAN — Wireless Wide Area Network
• FCA — Free Carrier Absorption
• SPM — Scanning Probe Microscope
• SMR — Specialized Mobile Radio
• PG — Page
• MIPS — Millions of Instructions Per Second
• SZ — Seizure
• JIT — Just in time
• TMS — Time Management System
• CFA — Carrier Facility Assignment
• ESTEC — European Space Research and Technology Centre
• PIC — Peripheral Interface Controller
• LLU — Local Loop Unbundling
• BS — Backing Store
• RSVD — Reserved
• VOA — Voice Of America
• BBM — Blackberry Messenger
• AT&T — American Telephone and Telegraph (U.S. company, also known as "Ma Bell")
• DSN — Deep Space Network - network of large antennas and communication facilities.
• VAZO — Violating All-Zero Octet
• SRM — Scalable Reliable Multicast
• C — Cost
• TLK — Talk
• DNIS — Dialed Number Identification Service
• CRC — Contrôle de Redondance Cyclique (French: Cyclic Redundancy Check)
• BSS — Basic Service Set
• EM — Electromigration
• SOAP — Simple Object Access Protocol
• NMR — Nuclear Magnetic Resonance
• FRS — Family Radio Service
• SIL — Silence
• PMP — Project Management Professional
• SA — Source Address
• TCR — Temperature Coefficient of Resistance
• KBYTE — Kilobyte (103)
• ATC — Advanced Technology Center
• JAN — Joint Army-Navy
• NNTP — Network News Transfer Protocol
• EMC — Electromagnetic Compatibility
• SOGA — Share of Gross Adds
• DDL — Digital Data Link
• ASP — Application Service Provider
• DPL — Digital Power Line
• BSS — Base Station Subsystem
• BPDU — Bridge Protocol Data Unit

• NTIA — National Telecommunications and Information Administration
• EFIS — Electronic Flight Information System
• EDD — Envelope Delay Distortion
• ASI — Asynchronous Serial Interface
• VG — Voice Grade
• TAD — Telephone Answering Device
• QPSK — aeronautical quadrature phase shift keying
• SABGW — System Architecture Evolution Gateway
• MAI — Multiple Access Interference
• CB — Citizens' Band
• DTMF — Dual-Tone MultiFrequency
• DIBL — Drain-induced Barrier Lowering
• SIC — Standard Industrial Classification (Code)
• LDAP — Lightweight Directory Access Protocol (pronounced Ell-dap)
• SIM — Subscriber Identity Module
• MME — Mobility Management Entity
• VT — Virtual Terminal
• EEG — Electro-EncephaloGram
• MV — Motion Vector
• SATAN — Security Administrator Tool for Analyzing Networks
• CGSA — Cellular Geographic Service Area
• CAPS — Call Attempts Per Second
• PC — Peripheral Controller
• ITP — Interactive Telecommunications Program
• RP — Reference Point
• ACLR — Adjacent Channel Leakage Ratio
• WTLS — Wireless Transport Layer Security
• PVD — Physical Vapor Deposition
• S/D — Source/Drain
• COM — Comedy Central
• O/S — Operating System
• BOD — Bandwidth on Demand
• DID — direct inward dial
• CQA — Certified Quality Auditor
• DCN — Design Change Notification
• B3G — Beyond Third Generation
• EEA — European Economic Area
• FTTH — Fiber To The Home
• PKI — Public Key Infrastructure (cryptography)
• DSP — Digital Signal Processor
• SLV — Satellite-Launch Vehicle
• VC-ATOD — Virtual Clearinghouse on Alcohol, Tobacco and Other Drugs
• SML/SMS — Service Management Layer/Service Management Service
• EDP — Electronic Data Processing Plc (London Stock Exchange [LSE])
• ARIN — American Registry for Internet Numbers
• SRS — Software Requirements Specifications
• WE — Western Electric
• MTU — Maximum Transmission Unit
• DL — Data Link
• PBX — Private Branch eXchange (company phone system)

• AFM — Atomic Force Microscopy
• SQ — Service Quality
• ISM — Industrial, Scientific and Medical
• SN — Service Number
• CBWFQ — Class Based Weighted Fair Queueing
• SB — Switchboard
• TCO — Total Cost of Ownership
• CS-PDU — Convergence Sublayer - Protocol Data Unit
• CDA — Command and Data Acquisition
• OSCAR — Orbiting Satellite Carrying Amateur Radio
• MX — Mixer
• PDT — Portable Data Terminal
• RTU — Remote Terminal Unit
• MDF — Main Distribution Frame
• STD — Subscriber Trunk Dialing
• FSK — Frequency-Shift Keying
• FRS — Frame Relay Service
• CLI — Command line Interface (Cabletron)
• WLAN — Wireless Local Area Network
• CST — Central Standard Time (UTC-6 Hours)
• SD — Speed Dial
• DTI — Department of Trade and Industry (UK)
• E&M — ear and mouth (special signaling leads)
• MIDP — Mobile Information Device Profile
• MLP — Mobile Location Protocol
• LQR — Linear Quadratic Regulator
• ABN — Abnormal
• SAE — Society of Automotive Engineers
• BAN — Base Area Network
• CTU — Central Terminal Unit
• OSTP — Office of Science and Technology Policy
• DMI — Distributed Management Interface
• ES — Emergency Service
• SCADA — Supervisory Control And Data Aquisition
• WDN — Wireless Developer Network
• SLIC — Subscriber Line Interface Circuit
• FCC — Federal Communications Commission (US)
• CPC — Continous Packet Compression
• FR PVC — Frame Relay Permanent Virtual Connection
• SG — Signaling Gateway (IETF)
• MIB — Management Information Base (ATM)
• AP — Action Point
• COPS — Common Open Policy Service
• TAM — Telephone Answering Machine
• SPX — Sequenced Packet Exchange
• FASB — Financial Accounting Standards Board
• PCM — Pulse-Code Modulation
• AC — Area Code
• CAP — Capability
• CS — Central Station

• TOS — Temporarily Out of Service
• OLE — Object Linking and Embedding (Microsoft communication protocol)
• ASDE — Airport Surface Detection Equipment
• BRI — Basic Rate Interface
• NBS — National Bureau of Standards (US)
• LD — Laser Diode
• DII — Dynamic Invocation Interface
• CI — Common Interface
• TELECOMMUTE — Telecommuting
• FXS — Foreign Exchange Subscriber
• IANA — Internet Assigned Numbers Authority
• EAI — Enterprise Application Integration
• ISAS — Institute of Space and Astronautical Sciences (Japan)
• CSC — Common Signaling Channel
• TSE — Toronto Stock Exchange
• KHZ — kilohertz (1000 cycles per second)
• ECMA — European Computer Manufacturer's Association
• BA — Behaviour Aggregate
• ETF — Early Termination Fee
• RDS — Rate Determining Step
• RDF — Radio Direction Finder
• CGA — Carrier Group Alarm
• PABX — private automatic branch exchange (telephone)
• NTP — Network Time Protocol
• ACF — Access Control Field
• 2W — 2-Wire
• BIU — Bus Interface Unit
• UTC — Coordinated Universal Time
• DID — data item description
• CCSD — command communications service designator; control communications service designator
• FAS — Frame Alignment Signal
• NEMA — National Electric Manufacturer's Association
• MDM — Mobile Device Management
• DM — Domain Model
• NES — Network Encryption System
• MH — Message Handler
• DAP — Distributed Array Processor
• NPA — Numbering Plan Area
• BIOS — Basic Input Output System
• SCU — System Control Unit
• CT — Computer Terminal
• AYT — Are You There
• E — Electra
• BCH — Binary Coded Hexadecimal
• B2C — Business-to-Consumer
• AWT — Agence Wallonne des Télécommunications
• SDU — Signal Distribution Unit
• CIP — Carrier Identification Parameter
• CRO — Central Records Office
• V — Variable

• CMP — Connection Management Protocol
• GMRS — General Mobile Radio Service
• CPN — Cisco Powered Network
• PM — post meridian
• C — Collector
• DRM — Digital Rights Management
• CGA — Color Graphics Adapter
• SBU — Strategic Business Units
• DTN — Data Transfer Network
• TTY — Teletype Telex Machine
• TUR — Trunk Utilization Report
• POTS — Plain Old Telephone Service (FCW)
• NTIS — National Technical Information Service Technology Administration
• CE — Channel Element
• RTC — Real-Time Control
• SSRC — Synchronization Source
• C4 — Command, Control, Communications, and Computers
• ARINC — Aeronautical Radio Incorporated
• PSS — Performance Support System
• ACP — Access Control Point
• PU — Physical Unit (IBM)
• SPIN — Service Provider Identification Number
• CIS — Computer and Information Science
• DC — Device Control
• FTTB — Fiber To The Building
• ODBC — Open Database Connectivity
• BMS — Business Management System
• BSS — Base Station System
• ER — Extended Range
• CFO — Communication Filing Officer
• PM — Phase Modulation
• BJT — Bipolar Junction Transistor
• SIA — Securities Industry Association
• SM — Service Module
• VOIP — Voice Over IP (Internet Protocol)
• APS — Automatic Protection Switching (SONET/SDH)
• IMP — Interface Message Processor
• BIS — Business Information System
• CMS — Content Management System
• P — Priority
• PM — Project Manager
• SDLC — Synchronous Data Link Control
• AIF — Audio Interchange Format
• NCSC — National Computer Security Center (NSA)
• ESF — Edge Spread Function
• AIT — Automatic Identification Technology
• SIT — Static Induction Transistor
• VGA — Video Graphics Array
• FLM — First Line Maintenance
• CP — Call Processing

• EU — End User
• YYP — Yahoo Yellow Pages
• CIFS — Common Internet File System
• TDOA — Time Difference Of Arrival
• KAK — Key-Auto-Key
• SPA — Software Publishers Association
• TDM — Time Division Multiplexer
• TOA — Time Of Arrival
• XPS — X-Ray Photoelectron Spectroscopy
• EPR — Ethylene-Propylene Rubber
• ESP — Encapsulating Security Payload
• STA — State
• CVR — Crystal Video Receiver
• EIGRP — Enhanced Interior Gateway Routing Protocol
• WAYP — White and Yellow Pages
• 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
• IRS — Inertial Reference System
• SN — Stock Number
• WPAN — Wireless Personal Area Network
• MMU — Memory Management Unit
• 100BASE-T4 — 100 Megabits per Second, Baseband, Four-pair Category 3 UTP cables
• CFD — Call For Discussion
• PIM — Personal Information Manager
• ARQ — Automatic Repeat-reQuest
• ADT — American District Telegraph Company
• T — Temperature
• ASD — Alternative Service Delivery
• SW — South West
• C³CM — Command, Control and Communications Countermeasures
• WAR — Weekly Activity Report
• IOC — Inter-Office Channel
• AN — Access Node
• AWG — American Wire Gauge
• PAP — Password Authentication Protocol (ATM)
• DHD — Dial Home Device
• SSM — Synchronization Status Message
• RSS — Really Simple Syndication
• LASA — Large Aperture Seismic Array
• CORBA — Common Object Request Broker Architecture
• SHA — Secure Hash Algorithm
• TAX — Trunk Automatic Exchange
• MPI — Minimum Picture Interval
• SSM — Spread Spectrum Modulation
• PDN — Packet Data Network
• BOSS — Binary Object Storage System
• IRC — International Record Carrier
• ADC — Administration Center
• OC-9 — Optical Carrier Signal, Level 9
• WIPO — World Intellectual Property Organization
• ADN — Abbreviated Dialing Number

• HVAC — Heating, Ventilation, and Air Conditioning
• CHF — Swiss Franc
• FM — frequency modulation
• ST — Such That
• ADT — Atlantic Daylight Time (UTC-3 Hours)
• ECM — Electronic Counter Measures
• ACTV — Active
• REPT — Report
• EHF — Extremely High Frequency
• ISBN — International Standard Book Number (ISO 2108)
• TRS — Telecommunications Relay Service
• RSN — Real Soon Now [which may be a long time coming]
• JPEG — Joint Photographic Experts Group (24-bit image storage format)
• FDTD — Finite Difference Time Domain
• UN — United Narions
• SVP — Senior Vice President
• IAT — Integrated Access Terminal
• DPL — Digital Private-Line
• UI — User Interface
• 911 — Emergency Services Phone Number
• CG — Center of Gravity (DXS)
• TOVS — TIROS Operational Vertical Sounder
• 100BASE-T — 100 Megabits per second, Baseband, Twisted pair
• OC-18 — Optical Carrier Signal, Level 18
• PVC — Permanent Virtual Connection
• OTDOA — Observed Time Difference of Arrival
• IPM — Inches Per Minute
• CFD — computational fluid dynamics
• DDU — Disk Drive Unit
• CP — Change Proposal
• MA — Maintenance Action
• DSLAM — Digital Subscriber Line Access Multiplexer (Module)
• SDH — Synchronous Digital Hierarchy (ATM)
• PMT — Program Management Team
• NOC — Network Operations Center
• CONUS — Contiguous United States
• MIT — Massachusetts Institute of Technology (U.S.)
• PVC — Permanent Virtual Circuit (ATM)
• DTD — Document Type Definition (XML)
• OSP — Outside Plant
• ET — Electronic Transmission
• DS-0 — Digital Signal, Level 0
• CMD — Command
• PPARC — Particle Physics and Astronomy Research Council
• SAF — System Access Fee
• MC — Maintenance Control
• GI — Graded-Index
• DGPT — Directorate General of Posts and Telecommunications
• 1FB — Single line, Flat Business rate;
• BUS — Business

• RSVP — Resource Reservation Protocol (Internet)
• RMI — Remote Method Invocation
• CAM — Common Access Method
• AVL — Available
• AVR — Automated Voice Response
• IEC — Interexchange Carrier
• MTS — Message Transfer System
• B2B — Business to Businesse
• EDC — Electronic Dispersion Compensator
• NF — Noise Factor
• FOSE — Federal Office Systems Exposition
• MA — Message Analysis
• BOFH — Bastard Operator From Hell
• RAN — Radio Access Network
• EGP — Exterior Gateway Protocol
• DTAP — Direct Transfer Application Process
• CRTS — Cellular Radio Telecommunications Service
• BMEWS — Ballistic Missile Early Warning System (bee-mews)
• MPEG — Motion Picture Experts Group
• CND — Calling Number Display
• KB — Kilobyte: One thousand and twenty-four bytes kbps kilo bit per second
• ASA — Acoustical Society of America
• SDK — Software Development Kit (Microsoft)
• RXQUAL — Received Signal Quality
• AOL — America on line
• 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)
• COO — Cell of Origin
• PCI — Personal Computer Interface
• TCIC — Trunk Circuit Identification Code
• AIFF — Audio Interchange File Format
• ORB — Object Request Broker
• LNP — Local Number Portability
• DCA — Dynamic Channel Assignment
• FAX — Facsimile
• LS — Loop Start
• ALT — Accelerated Life Test
• VSAT — Very Small Aperture Terminal (satellite service)
• IMC — Intermediate Metal Conduit
• HEHO — Head End Hop Off
• DL — Definition List
• INSAT — Indian National Satellite
• ACAP — Application Configuration Access Protocol
• HSS — Home Subscriber Server
• ILEC — Incumbent Local Exchange Carrier
• EISA — Extended Industry Standard Architecture
• MP — Modulation Parameter
• CMRS — Commercial Mobile Radio Service
• TL1 — Transaction Language 1
• ISSN — International Standard Serial Number (ISO 3297)
• NIST — National Institute of Standards & Technology (US)

• AP — access point
• DM — Differential Mode
• UDP — Up Down Pair
• MSW — Most Significant Word
• ANI — Automatic Number Identification (Caller ID)
• RMS — root mean square (preferred over "RMS")
• CRV — Call Reference Value
• PP — Polypropylene
• 2W — Two Wire
• DSI — Digital Speech Interpolation
• SAR — synthetic aperture radar (satellite)
• AOS — Alternate Operator Service
• SCM — Supply Chain Management
• COT — Central Office Terminal
• IRS — Interface Requirements Specification
• TTY — Text Teletype
• ROTFL — Roll On The Floor Laughing
• CFV — Call For Vote(s)
• EC — European Community
• DAT — Digital Audio Tape
• DTI — Digital Trunk Interface
• CGM — Computer Graphics Metafile
• DNIC — Data Network Identification Code
• 3-D — 3-Dimensional
• VMS — Virtual Memory System
• DCE — Data Communication Equipment
• SWAP — Shared Wireless Access Protocol
• TSO — Telecommunications Service Order
• NRPB — National Radiological Protection Board
• ALOC — Average Length Of Call
• RAU — Remote Access Unit
• UPS — Uninterruptible Power Supply
• EMCON — Electromagnetic Emission Control
• ELT — Emergency Locator Transmitter
• VF — Voice Frequency
• BSA — Business Software Alliance
• D-RAM — Dynamic Random Access Memory
• EFT — Electronic Funds Transfer
• CDE — Common Desktop Environment
• ALB — Analog Loopback
• WPM — speech--words per minute
• QDR — Quad Data Rate
• CIC — Carrier Identification Code
• WAIS — Wide Area Information Server
• LDN — Local Directory Number
• CIP — Channel Interface Processor
• IG — Interface Group
• IPS — InPlane Switching
• MIME — Multipurpose Internet Mail Extension
• DVB — Digital Video Broadcasting

• MLM — Multi-Longitudinal Mode
• SPGA — Staggered Pin Grid Array
• WHT — Walsh-Hadamard Transform
• SDM — Service Delivery Management
• CD — Critical Dimension
• JTF — Joint Task Force
• ICL — Inserted Connection Loss
• EMR — Electromechanical Relay
• MGMT — Management
• BAN — Building Area Network
• GDM — GSM (Global System for Mobile communications) Data Module
• DDI — Direct Dialing Incoming
• VOC — Volatile Organic Compounds (air pollution)
• PST — Pacific Standard Time (UTC-8 Hours)
• HTML — Hyper Text Markup Language
• CCCH — Common Control Channel
• ILD — International Long Distance
• OML — Object Model Library
• T&C — Terms & Conditions
• SN — Switching Network
• LIF — Logical Interchange Format
• TT — Text-Telephone
• CSPDN — Circuit Switched Public Data Network
• CCD — Charge Coupled Device - a device for the movement of electrical charge.
• FOD — Fax on Demand
• KDC — Kerberos Key Distribution Center
• AAV — Accountholder Authentication Value
• ISAKMP — Internet Security Association and Key Management Protocol
• CAL — Calorie
• DMS — Data Management System
• AFOSR — Air Force Office Of Scientific Research(USA)
• RDT — Recall Dial Tone
• OC-256 — Optical Carrier Signal, Level 256
• EDT — Eastern Daylight Time
• FEP — Front End Processor
• APPL — Application
• RRN — Routing Recording Number
• HDSL — High-bit-rate Digital Subscriber Line
• COAX — Coaxial
• TKIP — Temporal Key Integrity Protocol
• LANE — Local Area Network Emulation
• CMA — Communications Management Association
• 3GPP — Third Generation Partnership Project
• NSS — Network Switching Subsystem
• RSL — Restricted Service License
• COMDEX — Computer Dealers Exposition
• COC — Central Office Connection
• SIL — Solid Immersion Lens
• TAG — Technical Advisory Group for Biological Control Agents of Weeds
• MR — Mobile Router

• WFA — Wait for Answer
• FGA — Feature Group A
• ADC — Access Deficit Charge
• DNS — Domain Name Service
• ISOC — Internet Society
• SRR — Search and Rescue Region
• 3G — 3rd Generation Wireless Format
• ACPI — Advanced Configuration and Power Interface
• PACS — Personal Access Communications System
• FDI — Feeder Distribution Interface
• VPA — Valid Peripheral Address
• ACA — Adaptive Channel Allocation
• CCP — Compression Control Protocol
• USA — Underground Service Alert
• 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
• AWACS — Airborne Warning And Control System
• SPD — Serial Presence Detect
• LOO — Likelihood of Occurrence
• GAN — Global Area Network
• EEROM — Electronically Erasable Read-Only Memory
• JCL — Job Control Language
• SIM — Subscriber Identification Module
• DSS — Digital Signature Standard
• FITL — Fiber-In-The-Loop
• LISP — List Processing Language
• OFC — Office
• MBPS — Megabits per second
• FGD — Feature Group D
• CDM — Conceptual Data Model
• FEC — Forward Error Correction
• SCPC — single channel per carrier
• DDD — Direct Distance Dialing
• CPC — Calling Party Control
• WAP — Wireless Application Protocol
• TDMA — Time Division Multiple Access
• L2TPV3 — Layer 2 Tunneling Protocol Version 3
• DEMUX — Demultiplexer
• VN — Virtual Network
• CAD — Computer-Aided Design
• BIS — Brought Into Service
• BT — Burst Tolerance
• WVOIP — Wireless Voice over Internet Protocol
• JRE — Java Runtime Environment
• EBS — Electron Bombarded Silicon
• FWA — Fixed Wireless Access
• FI — Format Identifier
• NIU — Network Interface Unit
• FAT — File Allocation Table
• SMS — Service Management System
• CNG — Fax Calling Tone

• RNX — Restricted Numeric eXchange
• IPS — Instructions Per Second
• TCB — Telecommunication Certification Body
• RCC — Radio Common Carrier
• VPI — Virtual Path Identifier
• SSN — Switched Service Network
• DPT — Dynamic Packet Transport
• EOB — End Of Business
• WMO — World Meteorological Organization (ICSU)
• ICANN — Internet Corporation for Assigned Names and Numbers
• SDP — Software Development Plan
• CBR — Constant Bit Rate
• CLETS — California Law Enforcement Telecommunication System
• BLOS — Beyond Line-Of-Sight
• MBWA — Mobile Broadband Wireless Access
• NC — Network Channel
• ADB — Apple Desktop Bus
• EVA — Electronic Video Agent
• DVMRP — Distance Vector Multicast Routing Protocol
• 2G — Second Generation Wireless Systems
• DDN — U.S. Defense Data Network
• CSO — Customer Service Operations
• CES — Consumer Electronics Show
• CRLF — Carriage-Return Line-Feed
• LMS — Learning management system
• TC — Transmission Convergence (ATM)
• ISG — Information Systems Group
• USGS — United States Geological Survey (DOI)
• OSS — Operations Support System
• DER — Distinguished Encoding Rules
• APDU — Application Protocol Data Units
• BSC — Bi-Synchronous Communications
• LATA — Local Access and Transport Area
• TFTP — Trivial File Transfer Protocol (ATM)
• CRIS — Carrier Route Information System
• FAC — Forced Authorization Code
• GHZ — Gigahertz
• DII — Defense Information Infrastructure
• EIA — Extended Interaction Amplifier
• QI — Quality Indicator
• COMINT — Communications Intelligence
• CRS — Cell Relay Service
• DUA — Directory User Agent
• TU — Transmission Unit
• LRC — Learning Resource Center
• PROM — Programmable Read-Only Memory
• DSCP — Differentiated Services Code Point
• JDK — Java Development Kit
• EA — Extended Address Field Bit
• 4W — Four-Wire

• IP — Intellectual Property
• VTS — Vessel Traffic Service
• RICK — Repeater Interface Communications Kit
• CV — Coding Violation
• ATS — Abstract Test Suite
• ARM — Asynchronous Response Mode
• EMS — Express Mail Service
• DPA — Distributed-Power Architecture
• OSHA — Occupational Safety and Health Act (1970)
• GBT — Ground Based Tower
• IR — International Roaming
• FC — Frame Control
• BCH — Bose-Chaudhuri-Hocquenghem Coding
• CLK — Clock
• RP — Radio Port
• FEP — Front-End Processor
• B6ZS — Bipolar 6 Zero Substitution
• TD — Transmit Data
• KM — Knowledge Management
• CLDC — Connected Limited Device Configuration
• OOP — Object-Oriented Programming
• NAT — Network Address Translation
• SOS — Save Our Souls (Help!)
• CSR — Customer Service Report
• TOMS — Total Ozone Mapping Spectrometer (satellite Instrument)
• OT — Office of Telecommunications
• DIL — Direct Inward Line
• IMEI — International Mobile Equipment Identity
• CFNRY — Call Forwarding on No Reply
• DPDU — Data Protocol Data Unit
• B-ISDN — Broadband Integrated Services Digital Network
• ABM — Asynchronous Balanced Mode
• RCU — Radio Control Unit
• EULA — End User License Agreement (usually in reference to software)
• 3GPP — Third-Generation Partnership Project
• IEEE — Institute of Electrical and Electronics Engineers
• NDVI — Normalized Difference Vegetation Index
• ACC — Area Control Center
• RMON — Remote Monitoring
• PD — Pulse Duration
• SCR — Sustainable Cell Rate
• OTA — Office of Technology Assessment (U.S.; abolished by Congress, Fall 1995)
• SCR — System Change Request
• SPC — Statistical Process Control. Forerunning quality theory from the 1960s to TQC and TQM.
• NCF — Network Control Facility
• DLP — Data Link Processor
• MCC — Mission Control Center (JSC)
• CACH — Call Appearance Call Handling
• CSPRM — Common Signaling Protocols Resource Module
• DSN — Defense Switched Network

• PAM — Payload Assist Module
• TCA — Threshold Crossing Alert
• EBCDIC — Extended Binary-Coded Decimal Interchange Code
• VLSI — Very-Large-Scale Integration
• ESCON — Enterprise System Connection
• VSAT — Very Small-Aperture Terminal
• UART — Universal Asynchronous Receiver/Transmitter
• RDI — Remote Defect Indicator (UNI Fault Management)
• CMIP — Common Management Information Protocol (ATM)
• CIRC — Cross-Interleaved Reed-Solomon Code
• ADM — Administration Building
• DARTS — Design Approach for Real-Time Systems
• STMR — Sidetone Masking Rating (telecommunications)
• TDD — Time Division Duplex
• WTS — Wireless Telecommunications Symposium
• INE — Intelligent Network Element
• NAFTA — North American Free Trade Agreement
• BSI — British Standards Institution
• BLER — Block Error Rate
• INTELSAT — International Telecommunications Satellite
• CPS — characters per second
• FCA — Fixed Channel Allocation
• PCMCIA — Personal Computer Memory Card International Association
• DCS — Data Collection System (NOAA Polar Orbiting Satellites)
• CID — Craft Interface Device
• DXC — Digital Cross Connect
• OMF — Object Management Framework
• ECR — Electronic Cash Register
• ISI — Intersymbol Interference
• HFC — Hybrid Fiber/Coaxial network
• DN — Distinguished Name
• ROS — Return on Sales
• MMM — Mobile Media Mode
• BER — Basic Encoding Rules (ASN.1)
• IRDA — Infrared Data Association
• HDML — Handheld Device Markup Language
• SAT — Satellite
• LRC — Longitudinal Redundancy Check
• ECP — Engineering Change Proposals
• JST — Japan Standard Time
• IAB — Internet Architecture Board
• EIR — Equipment Identity Register
• IMSI — International Mobile Subscriber Identity
• ECE — Economische Commissie voor Europa (United Nations) (Dutch: Economic Commission for Europe)
• RMS — Resource Management System
• MSDP — Multicast Source Discovery Protocol
• NAS — Network-Attached Storage
• SCM — Single-Carrier Modulation
• EMS — Element Management System (ATM)
• DPSK — Differential Phase Shift Keying

• ULL — Unbundled Local Loop
• EDFA — Erbium-Doped Fiber Amplifier
• CALEA — Communications Assistance for Law Enforcement Act
• MGC — Multimedia Gateway Controller
• MFC — Multi-Frequency Code
• LIDB — Line Information DataBase
• CLD — Cross-Layer Design
• WTO — World Trade Organisation
• GS — Ground Start
• CIAC — Computer Incident Advisory Capability
• AWG — arrayed waveguide grating
• VDR — Voice Digitization Rate
• UCF — Unregistration Confirm
• WDA — Wireless Digital Assistant
• DA — deca
• LSW — Least Significant Word
• TSC — Test System Controller
• OMP — Open Management Platform
• BCDIC — Binary Coded Decimal Interchange Code
• CCR — Customer Controlled Reconfiguration (Sprint)
• RJE — Remote Job Entry
• RLU — Remote Line Unit
• SSP — Security Service Provider
• ADCCP — Advanced Data Communication Control Procedures
• AT — Attenuation
• NRP — Network Resource Planning
• MF — Multiple Frequency
• HEX — Hexadecimal (base 16)
• IRQ — Interrupt Request
• VBA — Visual BASIC for Applications
• RADIUS — Remote Authentication Dial-In User Service
• HLR — Home Location Register
• RFR — Radio Frequency Radiation
• CRB — Cramer-Rao Bound
• ACSE — Association Control Service Element
• CTO — Commonwealth Telecommunications Organisation
• ANC — Access Network Controller
• LI — Length Indicator
• DCAS — Downloadable Conditional Access System
• AF — Assured Forwarding
• CPG — Converged Packet Gateway
• VR — Virtual Router
• SUS — Suspension
• FNN — Full National Number
• CAPTAIN — Character And Pattern Telephone Access Information Network
• CRBT — Caller Ring Back Tone
• ETN — Electronic Tandem Network
• LCF — Location Confirm
• EBIC — Electron Beam Induced Current
• AMPS — Advanced Mobile Phone Service (cellular phone standard)

• YA — Yet Another
• 4WAI — Four-Wire Analog Interface
• UMA — Unlicensed Mobile Access
• FH — Frequency Hopping
• ASN.1 — Abstract Syntax Notation 1
• PDL — Positioning Data Link
• TRS — Trunked Radio Systems
• TP — Telephone Pole
• FECN — Forward Explicit Congestion Notification (ATM)
• EMF — Event Management Framework
• FTTC — Fiber To The Curb光纤到路边
• VLAN — Virtual Local Area Network
• BHCA — Busy Hour Call Attempt
• UMTS — Universal Mobile Telecommunications Service
• SSMA — Spread-Spectrum Multiple Access
• 2G — Second generation cellular
• IAD — Integrated Access Device
• CHTML — Compact Hypertext Markup Language
• TBCD — Telephony Binary Coded Decimal
• WAE — Wireless Application Environment
• CMOS — Complementary Metal Oxide Semiconductors
• RSS — Radio Service Software (Motorola)
• APN — An Access Point Name
• AMSS — Automatic Message Switching System
• SNA — System Network Architecture
• WSDL — Web Services Description Language
• DISN — Defense Information Systems Network
• VPX — Virtual Path Cross-Connect
• YABA — Yet Another Bloody Acronym
• LCR — Least Cost Routing
• SE — Southeast
• DCF — Distributed Coordination Function
• CTE — Computer Telephony Engineer
• AMPS — Advanced Mobile Phone System
• DTE — Digital Terminal Equipment
• ASAR — Advanced Synthetic Aperture Radar 
• QS — Quasi-Synchronous
• PNP — Plug-and-Play
• FEXT — Far-End Cross Talk
• LB — Local Battery
• LH — Link Handler
• OBC — Onboard Computer
• ASEAN — Association of South East Asian Nations
• NLM — National Library of Medicine (National Institutes of Health)
• CPAP — Customer Premises Access Profile
• ASQ — Alpha System Qualification
• OSF — Open Software Foundation
• SISIR — Singapore Institute of Standards and Industrial Research
• NAK — Negative Acknowledge
• RSS — root-sum-square

• PEM — Privacy-Enhanced Mail
• WARC — World Administrative Radio Conference
• MHO — My Humble Opinion
• ALI — Automatic Location Information
• CAVE — Cellular Authentication and Voice Encryption Algorithm
• RAU — Radio Access Unit (Army)
• SITA — Société Internationale de Télécommunications Aéronautiques
• TCC — Transmission Control Code
• DOD — Direct Outward Dialing
• VBR — Variable Bit Rate (ATM)
• CBEMA — Computer & Business Equipment Manufacturers Association
• LAG — Link Aggregation Group
• TP — Termination Point
• SLAM — Scanning Laser Acoustic Microscope
• POP — Post Office Protocol
• VLSI — Very Large-Scale Integration
• AAS — advanced automation system (FAA)
• PCCA — Portable Computer Communications Association
• POE — power over ethernetinjector
• TP — Transition Point
• ADF — automatic document feeder
• RDMA — Remote Direct Memory Access
• VCI — Virtual Channel Identifier
• RISC — Reduced Instruction Set Computing
• TEI — Terminal Endpoint Identifier
• DE — Discard Eligibility (ATM)
• VNS — Virtual Network System
• SRL — Singing Return Loss
• ASN.1 — Abstract Syntax Notation One
• CON — Concentrator
• CTI — Computer Telephony Integration
• LEC — Local Exchange Carrier
• RDBMS — Relational Data Base Management System (Oracle)
• LCP — Local Control Point
• CPOP — Circuit Precedence Over Packet data
• RGN — Region
• P&A — Privacy and Authentication
• ET — Exchange Terminal
• DPDT — Double-Pole Double-Throw
• ADTM — Asynchronous Data Transfer Mode
• ECM — Error Correction Model
• FEA — Finite Element Analysis
• SPID — Service Profile Identifier
• DOD — Dial on Demand
• RCP — Right-Hand Circular Polarization
• TNI — Telephone Network Interface
• RTC — Right to Carry
• LRM — Long Reach Multimode
• TXM — Transmission X-ray Microscope
• DRQ — Disengage Request

• CT — Cordless Telecommunications
• EMI — Electro-Magnetic Interference
• CRBT — Color Ring Back Tone
• LT — Line Termination
• SMB — Server Message Block
• CIS — Center for Integrated Systems
• FMR — Follow Me Roaming
• ADPC — Automatic Data Processing Center
• DPCM — differential pulse code modulation
• ECS — Encryption Control Signal
• OD — Outside Diameter
• CSP — Converged Service Platform
• VHSIC — Very High-Speed Integrated Circuit
• WFA — Work Force Administration
• CAMA — Centralized Automatic Message Accounting
• DACS — Digital Access Cross-connect System
• NIMBY — Not In My Back Yard
• EST — Establish
• NCSA — National Center for Supercomputing Applications
• F — Frequency
• IPCP — Internet Protocol Control Protocol
• DTU — Data Transfer Unit
• 4WA — Four Wire Analog
• CC — Composite Clock (SONET)
• NFPA — National Fire Protection Association
• VOB — Versioned Object Base
• SCC — Specialized Common Carrier
• DDM — Data Distribution Manager
• EDSX — Electronic Digital Signal Cross-Connect
• FR — Functional Requirement
• AAP — Alternate Access Provider
• WINS — Windows Internet Name Service
• DFG — difference-frequency generation
• VOB — Voice Over Broadband
• ABBR — Abbreviation
• DRFM — Digital Radio-Frequency Memory
• SMDS — Switched Multimegabit Data Service (ATM)
• LXT — Local Exchange Terminal
• TEL — Telephone
• BP — Block Parity
• CDM — Configuration Data Manager
• TOC — Telecommunication Operations Center
• DIV — Divisionsion
• FMC — Fixed Mobile Convergence "Mobile UC or Unified Communications over Wireless"
• CLCC — Ceramic Leaded Chip Carrier
• WSFL — Web Services Flow Language
• BOM — Bit-Oriented Message
• ATS — Automatic Transfer Switch
• EM — Element Manager
• CTIA — Cellular Telecommunications Industry Association

• VPWS — Virtual Private Wire Service
• TTYL — Type To You Later
• YAHOO — You Are Hazy Over Oranges
• DCMI — Dublin Core Metadata Initiative (Online Computer Library Center)
• FTTK — Fibre To The Kerb
• ACF — Access Coordination Function
• WIN — Wireless Intelligent Network
• CODEC — Coder/decoder
• STP — standard temperature and pressure (0° and 1 atm)
• CSIRO — Commonwealth Scientific and Industrial Research Organization
• DDCMP — Digital Data Communications Message Protocol
• HSPA — High Speed Packet Access
• CM — Connection Manager
• TIFF — Tag Image File Format
• RPV — Remotely Piloted Vehicle
• RADIUS — Remote Authentication dial In User Service
• NII — National Information Infrastructure (USA)
• RAD — Recorded Announcement Device
• TLT — Test Loop Translator
• TED — Triteal Enterprise Desktop
• DPBX — Digital Private Branch Exchange
• AAV — Alternate Access Vendor
• CAC — Connection Admission Control (Asynchronous Transfer Mode)
• CBMS — Computer-Based Message System
• 3G — Third Generation (mobile communication system)
• BAM — Basic Access Module
• CCA — Carrier-Controlled Approach
• RDT — Remote Digital Terminal
• VQV — Voice Quality Value
• CSCW — Computer-Supported Cooperative Work
• RQMT — Requirement
• SXS — Step-By-Step
• TACSAT — Tactical Satellite
• CPH — Call Party Handling
• VESA — Video Electronics Standards Association
• DQDB — Distributed Queue Dual Bus
• X — X Window System
• AMOLED — Active Matrix Organic Light-Emitting Diode
• CICS — Customer Information Control System (IBM Mainframe Software; Kicks Or C-I-C-S)
• CCNA — Cisco Certified Network Associated
• UTL — Utility
• PTT — Push to Talk Technology
• VSAM — Virtual Storage Access Method
• PJC — Pointer Justification Count
• GLT — Great Lakes Telecom
• CPE — Customer Premise Equipment
• TCM — Time Compression Multiplexer
• AFPS — Automatic Facility Protection Switching
• AAL5 — ATM (Asynchronous Transmission Mode) Adaptation Layer 5
• PSN — Packet Switched Network

• ACT — ACTIVITY, ACTIVITIES
• ENV — Environment
• RX — Receive
• WTL — Wireless Transport Layer
• KSU — Key Service Unit
• PLL — Phase Locked Loop
• BSID — Base Station Identity
• SCE — Service Creation Environment
• LIM — Line Isolation Monitor
• CCNA — Cisco Certified Network Administrator
• DDSN — Digital Derived Services Network
• FMS — Fixed Mobile Substitution
• ARSR — Air Route Surveillance Radar
• ATD — Advanced Technology Demonstration
• FCA — Free Carrier Alongside
• HPN — Home Phone Network
• FOIP — Fax Over Internet Protocol
• DECCO — DISA Defense Commercial Communications Office
• CDVT — Cell Delay Variation Tolerance
• SMI — Structure of Management Information
• VCR — Videocassette Recorder
• SIGTRAN — Signaling Transport
• GDK — GIMP (GNU Image Manipulation Program) Drawing Kit
• BASIZE — Buffer Allocation Size
• DOCSIS — Data over Cable Service Interface Specification
• PBT — Polybutylene Terephthalate
• DLL — Digital Local Line
• FPS — Framing Pattern Sequence
• BIND — Berkeley Internet Name Domain
• VCC — Virtual Channel Connection (ATM)
• FMS — Fraud Management System
• NTDS — Naval Tactical Data System
• STN — Station
• NDS — Novell Directory Services
• VO — Voice Only
• 4G — Fourth Generation Wireless Systems
• BNC — Bayonet Neill-Concelman
• CIP — Continuous Improvement Program
• PTP — Point To point Protocol
• LDP — Label Distribution Protocol
• VSC — Vertical Service Code
• OSA — Open System Architecture
• ANAC — An Automatic Number Announcement Circuit
• ATB — Above-Ground Telecommunications Backbone
• VCA — Voice Connecting Arrangement
• LRQ — Location Request
• VLF — Vertical-Laminar-Flow
• PY — person-year
• EFCI — Explicit Forward Congestion Indication (ATM)
• ACF — Advanced Communications Function (IBM)

• NOAO — National Optical Astronomy Observatories (Tucson, AZ)
• CPT — Cellular Paging Teleservice
• TP — Transaction Processor
• CVD — Chemical Vapor Deposition
• CCIR — International Radio Consultative Committee (French Acronym)
• LLA — Link Level Access
• DAF — Directory Access Function
• AI — Adapter Interface
• DDU — Digital Data Unit
• DS0 — Digital Signal Zero
• VRML — Virtual Reality Modeling Language
• MB — Measured Business
• BY — Busy
• CCITT — Comit? Consultatif International T?l?graphique et T?l?phonique
• CNG — comfort noise generation
• BSS — Broadband Switching System
• APPC — Advanced Program-to Program Communications
• LMS — Location and Monitoring Service
• TPS — Telephone Preference Service
• SWBD — Switchboard
• MAP — Mobile Application Part
• LVM — Line Verification Module
• DIS — Draft International Standard
• PSDN — Public Switched Digital Network
• MPU — Main Processor Unit
• IPLC — International Private Leased Circuit
• ESA — Enhanced Subscriber Authentication
• TDD — Telecommunications Device for the Deaf
• UML — Unified Modeling Language (Object Management Group, OMG)
• IDF — Independent Distribution Frame
• SSAP — Source Service Access Point
• AUI — Attachment Unit Interface
• DAC — Digital-To-Analog Converter
• LIS — Lightning Imaging Sensor
• SCH — Synchronization Channel
• DOT — Department of Telecommunications (India)
• IBSS — Independent Basic Service Set
• NE — North-East
• CDV — Cell Delay Variation(ATM)
• LPD — Low Probability of Detection
• PM — Processable Mode
• TLP — Transmission Level Point
• DNSIX — Defense Network Security Information Exchange
• B8ZS — Binary Eight Zero Substitution
• PTP — Point to Point Transmission Service (electricity)
• NCP — Network Control Protocol
• BDFB — Battery Distribution Feeder Bay
• DXF — Data Exchange Format
• BC — Basic Call
• MITI — Ministry of International Trade and Industry

• TCP/IP — Transmission Control/Internet Protocol
• NE — Network Element
• TRX — Tandem Repeater eXchange
• CES — Circuit Emulation Service
• SONET — Synchronous Optical Network
• SPA — Special Prorate Agreement
• CMT — Commercial Metering Transponder
• BSA — Basic Service Area
• CDA — Communications Decency Act's
• C3I — Command, Control, Communications & Intelligence
• SMSC — Short Message Service Center
• IWF — Interworking Function
• TCS — Telephony Control Specification
• BELLCORE — Bell Communications Research, Inc.
• PARC — Palo Alto Research Center
• ESCA — photoelectron spectroscopy for chemical analysis
• WORM — Write-Once, Read-Many
• MCP — Microsoft Certified Professional
• LP — Line Pair
• PLE — Path Length Efficiency
• OXCO — Oven-Controlled Crystal Oscillator
• BPP — Billed Party Preference
• PUK — PIN (Personal Identification Number) Unlocking Key
• ADP — Automatic Data Processor
• 4GL — Fourth-Generation Language
• BAF — Bellcore AMA (Automatic Message Accounting) Format
• LULT — Line Unit/Line Termination
• CC — Country Code
• BTAM — Basic Telecommunications Access Method
• RECON — Reconnaissance
• DTL — Defense Telephone Link
• CDA — Communications Decency Act of 1996
• ELFEXT — Equal-Level Far-End Cross-Talk
• BCIX — Berlin Commercial Internet Exchange
• IPVX — Internet Protocol version X
• WNMS — Wireless Network Management System
• PLCP — Physical Layer Convergence Procedure
• SKU — Stockkeeping Unit
• ARFA — Allied Radio Frequency Agency
• SVC — Switched Virtual Circuit (ATM)
• PTT — Push to Talk Taster
• RBS — Robbed Bit Signaling
• NSAI — National Standards Authority of Ireland
• CMC — Career Management Center
• AB — Answer Back
• AMP — amplifier / amplification
• WSA — Wireless Security Auditor
• MAG — Mobile Access Gateway
• ANSI-41 — ANSI standard for mobile management
• SIO — Service Information Octet

• OWS — Operator Work Station
• MSRN — Mobile Station Roaming Number
• ERL — Echo Return Loss
• DISA — U.S. Defense Information Systems Agency
• ATU-C — ADSL (Asymmetric Digital Subscriber Line) Transceiver Unit - Central office end
• NMS — NetWare Management System
• AMA — automatic message accounting
• SIP — Session Initiation Protocol
• SMPTE — Society of Motion Picture and Television Engineers, Inc.
• UCM — Use Case Map
• LSI — Large Scale Integration -> VLSI
• DLCI — data link connection identifier
• IESG — Internet Engineering Steering Group
• TBPS — Terabits Per Second
• PIC — Programmable Interrupt Controller
• WK — Week
• SMU — Service Management Unit
• MCR — Minimum Cell Rate (ATM)
• NREN — National Research and Education Network
• FTTP — Fiber To The Premises
• SAM — Service Access Multiplexer
• TSR — Terabit Switch/Router
• DMT — Discrete Multi-Tone Technology
• IMAP — Internet Mail Access Protocol
• OSD — Onscreen Display
• WAR — Wireless Access Revolution
• CLP — Cell Loss Priority (ATM)
• DS-3 — Digital Signal, Level 3
• EVC — Electronic Voucher Charging
• NFR — Near-Field Recording
• LSC — Link State Control
• CAR — committed access rate
• CGI — Cell Global Identity
• BDE — Borland Database Engine
• RACH — Random Access Channel
• DSCS — Defense Satellite Communication System
• BPSK — Binary Phase-shift Keying
• STU — Secure Telephone Unit
• COFA — Change Of Frame Alignment
• NCC — Network Control Center (GSFC)
• DSSSL — Document Style Semantics and Specification Language
• AAS — Automatic Announcement Subsystem
• SINAD — SIgnal-to-(Noise And Distortion) ratio
• TOP — technical/office protocol
• LBR — Low Bit Rate
• ISC — International Switching Center
• PDSO — Packet Data Security Overlay
• SR — Scanning Radiometer
• EGSM — Extended Global System for Mobile Communications
• FDOA — Frequency Difference Of Arrival

• VTAM — Virtual Telecommunication Access Method
• RADINT — Radar Intelligence
• TACACS — Terminal Access Controller Access Control System
• WNAP — Wireless Network Access Point
• BHCC — Busy Hour Call Completions
• IRTF — Internet Research Task Force
• CSU — Channel Service Unit
• MTD — Moving Target Detection
• ITT — Invitation To Tender
• SDSL — Symmetric Digital Subscriber Line
• RRC — Root Raised-Cosine
• CPS — Cycles Per Second (now Hertz)
• COP — Character Oriented Protocol
• ACM — Address Complete Message
• SQL — Specified Quality Level
• RIPE NCC — Reseaux IP Europeens Network Coordination Centre
• LFACS — Loop Facility Assignment and Control System
• NSAP — Network Service Access Point
• PMT — Photo Multiplier Tube
• DMS — Defense Messaging System
• RCT — remote Control Terminal
• SCCS — Switching Control Center System
• MGCP — Multimedia Gateway Control Protocol
• B-CPE — Broadband Customer Premises Equipment
• RCS — Radar Cross Section
• TRMM — Tropical Rainfall Measuring Mission (US-Japan)
• NT — New Technology, also Windows NT
• SIMT — Système interbancaire marocain de télécompensation
• B2B — Business-to-Business
• MMDS — Multichannel Multipoint Distribution Service
• SDP — Session Description Protocol
• NCOS — Network Class Of Service
• AEA — American Electronics Association's
• DNA — Do Not Answer
• EV — electronvolt
• LCAS — Link Capacity Adjustment Scheme
• P2P — Person-to-Person
• CQ — Communications Quality
• 1-ESS — x-ESS series of Electronic Switching Systems
• MAC — Message Authenticity Check
• DCO — Dial Central Office
• IOC — Interoffice Channel
• AMTFT — Active Matrix Thin Film Transistor
• DDLD — Direct Dial Long Distance
• MTS — Message Transmission Subsystem
• TDR — Time-Domain Reflectometry
• ALCAP — Access Link Control Application Protocol
• ASTD — American Society of Training and Development (Alexandria, Virginia)
• ASE — Application Service Element
• ATS — Air Traffic Services

• CCCI — Command, Control, Communications and Intelligence
• CEPT — Conférence Européenne des Administrations des Postes et des Télécommunications
• HTML — Hyper-Text Markup Language
• DMT — Discrete Multi-Tone
• TDWR — Terminal Doppler Weather Radar
• TRIG — Trigger
• MMSI — Maritime Mobile Service Identity
• ITA — Illinois Telecommunications Association
• GTB — Global Telecom Brokers
• SVI — Service Interception
• SES — Scientific and Engineering Software
• NCP — Network Control Program
• S/N — Signal-to-Noise ratio
• CU — Cooling Unit
• ATIS — Automatic Transmitter Identification System
• DCEF — Distributed Cisco Express Forwarding
• IPRC — Intellectual Property Rights Committee
• MPLS — Multi Protocol Label Switching
• CSR — Customer Service Request
• AAL — ATM (Asynchronous Transmission Mode) Adaptive Layer
• SDNS — Secure Data Network System
• HSCSWD — High-Speed Circuit-SWitched Data
• TSDU — Transport Service Data Unit
• 3GIP — Third Generation Internet Protocol
• PTT — Push to Talk Testing
• ACEK — Authentication Encryption Key
• DTR — Down-Time Ratio
• SGS — Software Generation System
• WFG — Wireless Firewall Gateway
• UDT — Unreliable Data Transfer
• NMC — Network Management Center
• USF — Universal Service Fund
• ALT — Automatic Link Transfer
• BT — Bluetooth Tablet
• CLASS — Cell Level ATM (Asynchronous Transfer Mode) Services Simulator
• RJ-14 — Registered Jack type 14 (2-wire connector)
• CBQ — Class-Based Queuing
• SPT — System Page Table
• FDD — Frequency Division Duplex
• ESN — Electronic Serial Number
• VSM — Vestigial Sideband Modulation
• LSAP — Link Service Access Point
• TARP — Target Identifier Address Resolution Protocol
• TACS — Total Access Cellular System
• FIOS — Fiber Optic Services
• DL — Downlink Message
• IVP — Integrated Voice Protocol
• SS7 — Signaling System 7
• SRA — Seamless Rate Adaptation
• DCC — Digital Control Channel

• PMMA — Polymethyl Methacrylate
• DLU — Digital Line Unit
• E — Echo Time Zone
• OIM — Operations Interface Module
• DMT — Discrete Multi-tone Transmission
• 4 GIG — 4 Giga Intellectual Gadget
• TDM — Time Division Multiplexing
• VFL — Visual Fault Locator
• LN — Line
• ESPN — Entertainment and Sports Programming Network
• FSK — Frequency Shift Keying
• UPT — Universal Personal Telecommunications
• UAT — Universal Access Transceiver
• CGI — Computer Graphics Interface
• DXI — Data Exchange Interface
• CSP — Continuous Speech Processing
• DAC — Digital to Analog Converter-Audio
• USF — Universal Server Farm
• DECT — Digital Enhanced Cordless Telecommunication
• UIH — Unnumbered Information with Header check
• DPNSS — Digital Private Network Signaling System
• SYM — Symmetric
• NW — North West
• UBR — Unspecified Bit Rate
• NCAR — National Center for Atmospheric Research (US)
• CCITT — Comite Consultatif International Telegraphique et Telephonique (now ITU-T)
• B-ISDN — Broadband ISDN
• DPST — Double-Pole Single-Throw
• CDV — Compressed Digital Video
• DUV — Data-Under-Voice
• IV&V — independent verification and validation
• SR — Slow Release
• QOD — Quality of Data
• CS — Connection Segment
• DNU — Do Not Use
• AMTI — Airborne Moving Target Indicator
• MMS — Multimedia Message Service
• IEEE-CS — Institute of Electrical and Electronics Engineers Computer Society
• DLT — Delete
• V — Vector
• ECS — Environmental Control System (Subsystem)
• AFRINIC — African Network Information Centre
• CEE — Communaut? Economique Europ?enne
• CCLC — Carrier Common Line Charge
• NEMP — Nuclear Electromagnetic Pulse
• QOI — Quality of Information
• MAPDU — Management Application Protocol Data Unit
• ASYNC — Asynchronous
• CSI — Clearing Subnetwork Identification
• URN — Uniform Resource Namespace

• PSN — Public Switched Network
• CSAR — Combat Search and Rescue
• BAN — Billing Account Number
• OCI — object code insertion
• MOS — Metal Oxide Semiconductor (FET Devices)
• STA — Science and Technology Agency (Japan)
• SRS — Supported Residential Services
• TSC — Technical Standards Committee
• CPN — Customer Premise Network
• ATRAC — Adaptive Transform Acoustic Coding
• D3 — Digital channel bank, Third generation
• LMS — Local Measured Service
• VGF — Voice Grade Facility
• COAM — Customer Owned And Maintained
• BHP — Burst Header Packet
• IDCU — Integrated Digital Carrier Unit
• SLF — Super Low Frequency
• SDCCH — Standalone Dedicated Control Channel
• MSI — Maritime Safety Information
• SMS — System Management Server
• APS — Advanced Power System
• AECT — Association for Educational Communications and Technology's
• DSP — Data Service Provider
• VAS — Value Added Services
• NTU — Network Termination Unit
• SPE — Synchronous Payload Envelope
• DICOM — Digital Imaging and Communications in Medicine
• RS-422 — Recommended Standard 422 (ANSI/EIA standard for transmitting serial data)
• VADB — Virtual Auto Dial Backup
• IR — Information Request
• SAPI — Service Access Point Identifier
• SPI — Security Parameters Index
• PMOS — P-channel Metal Oxide Semiconductor
• MBS — Maximum Burst Size (ATM)
• FSAI — Fiber Serving Area Interface
• DUV — Deep Ultraviolet
• ESP — Essential Service Protection
• STM — Synchronous Transfer Mode
• SDN — Software Defined Network
• IDCP — Internet Device Control Protocol
• CVT — Circuit Validation Test
• ATCA — Advanced Telecom Computing Architecture
• DACS — Digital Access Carrier System
• OCC — Occupancy
• GMSS — Global Mobile Satellite System
• MTI — Moving Target Indicator
• TTL — ToS and Time-to-Live
• PCS — Personal Communications Services
• BT — Back Trace
• FEM — Finite Element Method

• CCC — CDMA Cluster Controller
• BTS — Base Transceiver Station (cellular)
• ALI — Automatic Location Identifier
• LQC — Line Quality Control
• MTP — Message Transfer Part
• TSD — Type Specific Driver
• ANSI — Advanced Network Signaling Input
• UTP — Universal Transmission Protocol
• ACNA — Access Customer Name Abbreviation
• PET — positron emission tomography
• PIM — Protocol Independent Multicast
• DACS — Digital Access and Cross-Connect System
• ACA — Automatic Circuit Assurance
• SAR — Segmentation and Reassembly (ATM)
• CTTC — Centre Tecnològic de Telecomunicacions de Catalunya
• LMDS — Local Multipoint Distribution Service
• EPP — Enhanced Parallel Port (PC)
• DCS — Defense Communications System
• PSQM — Perceptual Speech Quality Measure
• OLS — Optical Line System
• SETI — Search for Extraterrestrial Intelligence
• CAMEL — Customized Applications for Mobile-network Enhanced Logic
• DCA — Distributed Communications Architecture
• ARPT — Autorité de Régulation des Postes et Télécommunications
• EA — expedited acknowledgement
• DW — Deep Water
• BSVCI — Broadcast Signaling Virtual Channel Identifier
• TM — Thematic Mapper (Landsat)
• OMA — Open Mobile Alliance
• SFN — Single Frequency Network
• AIU — Analog Interface Unit
• DORK — Disciples Of The Righteous King
• CFOT — Certified Fiber-Optic Technician
• TSGR — Transport System Generic Requirements
• TDRSS — Tracking and Data Relay Satellite System
• BUFR — Binary Universal Form for the Representation (of data)
• BSRF — Basic System Reference Frequency
• CSAA — Central Service Area Authority
• DNI — Data Network Interface
• SS1 — Signalling System 1 (500/20 Hz tones)
• ECC — Emergency Communications Center
• SNIX — Single Noise Interference Xterminator
• UNI — User-Network Interface
• ROW — Rest Of World
• MED — Manipulative Electronic Deception
• BTO — Betts Telecom Oklahoma
• RADSL — Rate Adaptive Digital Subscriber Line
• GSM — Groupe Speciale Mobile
• DNC — Do Not Call
• CSDU — Core Service Data Unit

• L2TP — Layer 2 Tunneling Protocol
• TPF — Transmission Priority Field
• PTM — Point-To-Multipoint
• MBE — Molecular Beam Epitaxy
• SEM — Scanning Electron Microscopes
• OOK — On/Off Keying
• WDMW — Web Directory for Mobile and Wireless
• AS — Active Service
• LDI — Long Distance Interconnect
• LMT — Lightwave Microcell Transceiver
• LAAS — Local Area Augmentation System
• TFL — Telecom Fiji Limited
• ANT — ADSL Network Terminator
• SLC — Service Level Contract
• EADAS — Engineering and Administrative Data Acquisition System
• A/D — Analog-to-Digital converter
• DBRNC — deciBel Relative to Noise in a Circuit
• HDTV — High-Definition Television
• WCDMA — Wideband Code Division Multiple Access
• FRAD — Frame Relay Access Device
• BB — Blackberry
• VGC — Voice Grade Channel
• GBPS — Gigabits per second
• CT — Control terminal
• WLTF — Wireless LAN (Local Area Network) Task Force
• DOITT — Department of Information Technology and Telecommunications
• IRF — Impulse Response Function
• TTY — teletype terminal
• SR — Service Request
• EMS — Enhanced Messaging Service
• GERAN — GSM (Global System for Mobile communications) Edge Radio Access Network
• RYP — Russian Yellow Pages
• AMR — Automated meter reading also known as Automatic Meter Reading
• CALA — Customer Address Location Area
• AGCH — Access Grant Channel
• MLA — Modern Language Association
• COBE — Corporate Owned Business Only
• QEDI — Quod Erat Demonstrandum
• IOS — Internet Over Satellite
• PLCP — Physical Layer Convergence Protocol (ATM)
• EST — Electroshock Therapy
• APR — Alarm Processing Remote
• SHR — Self-Healing Ring
• ISP — International Signaling Point
• MFLOPS — Millions of Floating Point Operations per Second
• DFE — Design For Environment
• INAP — Intelligent Network Application Part
• BCSM — Basic Call State Model
• ADTS — Ameritech Digital Transport Service
• DCSS — Digital Cross-connect Systems

• MEH — Mobile-Executed Handoff
• RFI — Remote File Inquiry
• RBT — Ring Back Tone
• SCC — Signal Conversion Circuit
• NLM — NetWare Loadable Module
• M/W — MicroWave
• TAE — Terminal Adapter Equipment
• 3G HSPA — Third-Generation High-Speed Packet Access
• TELNET — Telecommunications Network Protocol
• EMV — EuroPay, MasterCard, Visa
• SMG — Super Master Group
• LRF — Laser Range Finder
• MEECN — Minimum Essential Emergency Communication Network
• MILNET — Military Network
• BDSL — Broadband Digital Subscriber Line
• ARAI — Adjunct Route Application Interface
• PSK — Phase Shift Key
• RQMTS — Requirements
• MUSIC — MUltiple SIgnal Classification
• CERN — Conseil Europeen Pour La Recherche Nucleaire
• MDN — Mobile Directory Number
• VRT — Voltage Reduction Technology
• MP — Master Processor
• TC — Technical Committee (HL7)
• CAL — Customer Access Line
• CACM — Communications of the ACM
• PRM — Performance Report Message
• RCF — Remote Call Forwarding
• UMTS — Universal Mobile Telecommunications Standard
• ODS — Operational Data Store (knowledge management)
• CF — Coin First Payphone
• BNCC — Base Network Control Center
• KSPS — KiloSymbols Per Second
• CONS — Connection-oriented Network Services
• LOP-P — Loss Of Pointer - Path
• ARD — Automatic Ring Down
• CW — Call Waiting Supplementary Service
• 100VG — 100 Voice Grade (IEEE 802.12 AnyLAN Standard)
• ADTS — Automated Digital Terminal System
• LEED — Low-energy Electron Diffraction
• WSP — Wireless Service Provider
• CEPT — Conference of European Posts and Telecommunications
• DLT — Digital Line Termination
• DBN — Dial-Back Number
• PSC — Picture Start Code
• APS — American Protective Services
• TSI — time-slot interchange
• IPXCP — Internetwork Packet Exchange Control Protocol
• NESC — National Electrical Safety Code
• GFC — Generic Flow Control (ATM)

• LRB — Loop Reverse Battery
• DLE — Digital Local Exchange
• BHCA — Busy Hour Call Attempts
• SCO — Synchronous Connection Oriented
• TOMS — Telecom Operations Management System
• SMMR — Scanning Multichannel Microwave Radiometer
• ADPCM — Adaptive Differential Pulse Code Modulation
• VISSR — visible and infrared spin scan radiometer (GOES)
• PNP — Positive-Negative-Positive
• AEIMP — Apple Event Interprocess Messaging Protocol
• VXML — Voice eXtensible Markup Language
• NWK — Network
• PNE — Path Number Efficiency
• IEEE-SA — Institute of Electrical and Electronics Engineers - Standards Association
• MTA — Message Transfer Agents (Internet)
• HUMAN — High-speed Unlicensed Metropolitan Area Network
• SFX — Special Effects
• WAW — Wide Area Wireless
• BAOC — Barring of All Outgoing Calls supplementary service
• CMM — Calls, Minimums, Maximums
• MDCP — Media Device Control Protocol
• SA — Selective Availability (on GPS transmissions)
• RSI — Record Status Indicator
• E-TDMA — Expanded Time Division Multiple Access
• TIA — Telecommunications Industry Association
• FLL — Fixed-Loss Loop
• DPT — Dial Pulse Terminate
• MQFP — Metric Quad Flat Pack
• L2F — Layer 2 Forwarding protocol
• CDR — Common Data Rate
• SACS — Security Access Control System
• RNR — Receive Not Ready
• DEM — Digital Elevation Model
• FOC — Fiber-Optic Cable
• DCB — Digital Channel Bank (Sprint)
• BIC — Bus Interface Controller
• CMOS — Cellular Management Operation System
• RCR — Research and Development Center for Radio Systems
• CIPOA — Classical Internet Protocol over ATM (Asynchronous Transfer Mode)
• NICT — National Institute of Information and Communications Technology
• MOA — Managed Object Agent
• IDLC — Integrated Digital Loop Carrier
• OID — Object Interaction Diagram
• SDHLR — Super-Distributed Home Location Register
• WCMP — Wireless Control Message Protocol
• ISD — International Subscriber Dialling
• DEO — Digital End Office
• FTAM — File Transfer Access and Management
• DTW — Dynamic Time Warping
• MAJ — Major

• * — Star, special function key
• CM — Common Mode
• VOFR — Voice Over Frame Relay
• MCPC — Multiple Channels Per Carrier
• FAT — Final Acceptance Testing
• C² — Command and Control
• CSA — Canadian Standards Association (like UL)
• ICLD — Inter-Channel Level Difference
• CVSD — Continuous Variable Slope Detection
• HSCSD — High-Speed Circuit-Switched Data
• WIG — Wireless Internet Gateway
• PCIA — Personal Communications Industry Association
• ASAS — All-Source Analysis System
• CDDI — Copper Distributed Data Interface
• CLEC — Competitive Local Exchange Carrier
• DMT — Digital-Discrete Multi-Tone
• CNID — Calling Number Identification Display
• BSSMAP — Base Station System Management Application Part
• IPTD — Internet Protocol Telephony Design
• STE — Syrian Telecommunications Establishment
• USRT — Universal Synchronous Receiver/Transmitter
• CLI — Calling Line Identification
• LCGN — Logical Channel Group Number
• ADM — Administration, Office of
• DS-1 — Digital Signal, Level 1
• AIS-L — Alarm Indication Signal - Line
• STDM — Statistical Time Division Multiplexing
• WUP — Wired Up Privacy
• CAN — Controller Area Network
• ZD — Zero Defects
• CNE — Certified Novell Engineer
• CCSS6 — Common Channel Signaling System # 6
• RCMAC — Recent Change Memory Administration Center
• AIS-P — Alarm Indication Signal - Path
• SLIC — Subscriber Loop Interface Circuit
• DRTT — Dial Repeating Tie Trunk
• VGCP — Voice Grade Channel Processor
• CAM — Computer-Aided Manufacturing
• TMSI — Temporary Mobile Subscriber Identity
• CLIP — Caller Line Identification Presentation
• WFT — Wireline Formation Test
• APTC — Atlantic Provinces Telecommunications Council
• AL — Alignment
• CLOS — Clear Line Of Sight
• AIS-V — Alarm Indication Signal - Virtual
• MIN — Mobile Identification Number
• WCRL — Wireless Communications Research Laboratory
• MBMS — Multimedia Broadcast/Multicast Service
• CMAS — Cellular Management System
• GSTN — General Switched Telephone Network

• DORA — EV-DO (EVolution-Data Optimized) standard Revision A
• WPBX — Wireless Private Branch Exchange
• AAL2 — ATM (Asynchronous Transmission Mode) Adaptation Layer 2
• CODASYL — COnference on DAta SYstems Languages
• THL — Trans-Hybrid Loss
• AVT — Audio Visual Telecommunications
• VHM — Voice Health Monitor
• ECTF — Enterprise Computer Telephony Forum
• DX — Duplex Signaling
• CCR — Current Cell Rate (ATMF)
• MMC — Minimum Monthly Charge
• LAT — Local Area Transport (network)
• DMI — Desktop Management Interface (computing)
• BANC — Broadband Access Network Coordination
• ATU-R — ADSL (Asymmetric Digital Subscriber Line) Transceiver Unit - Remote terminal end
• NMC — Network Model Coverage
• TRANS — Transaction
• SVC — Single Voice Coil
• ACU — Automatic Calling Unit
• DAS — Data Acquisition System
• DPDCH — Dedicated Physical Data Channel
• ECDIS — Electronic Chart Display Information System
• GOS — Gerry Otis Simpson
• BHA — Busy Hour Attempts
• SNI — Service Node Interface
• E2E — End-to-End
• LSP — Label Switched Path
• TTC — Telemetry Telecommand and Control
• FD — Full Duplex
• ADM 3X — DS3 Add-Drop Multiplex
• MOD — Modulo
• DM — Design Manager
• AEE — Agent Execution Environment
• CAAS — Communications-as-a-Service
• WAWS — Washington Area Wideband System
• VTAC — Vermont Telecom Advancement Center
• 4G — Fourth Generation
• BSC — Base Station Controller
• MEAS — Measure
• INWATS — INward Wide Area Telecommunications Service
• RSN — Regional Service Network
• VPC — Virtual Path Connection (ATM)
• FAW — Frame Alignment Word
• NSN — National Significant Number
• AH — Authentication Header
• DCMES — Dublin Core Metadata Element Set
• APTG — Asia Pacific Telecom Group
• ATMS — automatic transmission measuring system
• CTSO — Cellular Telephone Service Order
• CCSA — Common Control Switching Arrangement

• MEID — Mobile Equipment Identifier
• TD-CDMA — Time Division - Code Division Multiple Access
• BATM — Basic Telecommunication Access Method
• MOC — Maintenance and Operations Console
• ATR — Advanced Telecommunications Research Institute
• RAI — remote alarm indication
• JISC — Japanese Industrial Standards Committee
• BRAN — Broadband Radio Access Network
• VF0 — Voice Fundamental Frequency
• IPC — Initial Paging Channel
• DSU — Digital Service Unit
• GSM — Global System for Mobile telecommunications
• LEC — Liquid Encapsulated Czochralski
• AAV — Alternative Access Vendor
• RCH — Receive Channel
• CR — Connection Request
• DLC — Digital Leased Circuit
• DMB — Disconnect and Make Busy
• COI — Community of Interest
• LTU — Line Termination Unit
• ASA — Avaya Site Administration
• ACL — Asynchronous Connection-less Link
• USPI — Universal Serial Phone Interface
• PTM — Packet Transport Mode
• F/W — Firmware
• WPKI — Wireless Public Key Infrastructure
• EDT — European Deaf Telephone
• NSE — Network Software Environment
• DCS — Digital Cross-connect Switch
• RZ — Return to Zero
• # — Number sign, octothorp; special function key
• DTS — Digital Terminal Systems
• ASP — Active Signaling Protocol
• MM — Multimode (fiber optic cable)
• BCM — Bit Compression Multiplexer
• NMC — Nortel Matra Cellular
• CTIT — College of Telecommunications and Information Technology
• ISO — Independent System Operator (US) (see also TSO) Responsible for grid management, but does not own assets. (electricity)
• UASL — Unified Access Service License
• WBMP — Wireless Bitmap
• CLF — Carrier Line Failure
• ESG — Enhanced Service Gateway
• MMC — Microsoft Management Console (Microsoft)
• ATL — Atlanta
• GPBX — Global Private Branch eXchange
• CARS — Community Antenna Relay Service
• WGX — Wireless Gateway Switch
• ERP — Enterprise Resource Management
• JMA — Japanese Meteorological Agency
• TPSP — Third Party Service Provider

• TME — Telocator Message Entry
• HSC — High Speed Connect
• EC — Entropy Coding
• 3GSM — Third-generation Global System for Mobile (communications)
• W-CDMA — Wideband Code Division Multiple Access
• ICTA — Idaho Cable Telecommunications Association
• JWG — Joint Working Groupof
• SM — Statistical Multiplexing
• SQE — Signal Quality Error
• SUBT — Subscriber Terminal
• CD — Committee Draft
• LAPB — Link Access Protocol-Balanced
• MTBM — Mean Time Between Maintenances
• ITOC — Independent Telephone Operating Company
• SSU — Synchronization Supply Unit
• AFIPS — American Federation of Information Processing Societies
• FOTS — Fiber Optical Transmission System
• GTM — Go to Meeting
• DF — Distributing Frame
• TRLR — Trailer
• ISSI — Inter-Switching System Interface
• SINS — Ship’s Inertial Navigation System
• MVDS — Microwave Video Distribution System
• PTCL — Pakistan Telecommunication Company Ltd
• VCT — Variable Cam Timing
• CL — cell loss
• LR-WPAN — Low-Rate Wireless Personal Area Network
• GOMP — Get Off My Phone
• DTU — Data Terminal Unit
• BFS — Broadcast File System
• KEK — Key Encrypting Key
• E — Exchange
• UDC — Universal Digital Channel
• CPC — Crosstalk Prevention Coding
• VC — Virtual Circuit (ATM)
• DF — Direction Finding or Finder
• REG — range extender with gain
• CFS — Customer Facing Services
• CCH — Common Channel Handler
• HDB3 — High-Density Bipolar Three-bit substitution
• WTP — Wireless Transaction Protocol
• DIP — Dialup Internet Protocol
• JWP — Joint Working Party
• UOS — Units of Service
• AFI — Authority and Format Identifier
• MNP — Microcomputer Networking Protocol
• MSC — Mobile Switching Center
• PSO — Professional Services Organization
• TVRO — Television Receive-Only
• BTE — Broadband Terminal Equipment

• RSL — Request and Status Links
• EF&I — Engineering, Furnishing and Installation
• JDC — Japan Digital Cellular
• PTI — Payload Type Indicator
• DE — Discard Eligible
• CUSA — Central Urban Service Area
• 4WE&M — Four-Wire Ear and Mouth
• ADIF — Accounting Data Interchange Format
• WTA — Wireless Telephony Application
• SCORM — Shareable Content Object Reference Model
• Z — Zulu Time
• UMTS — Universal Mobile Telecommunication System
• TBRL — Terminal Balance Return Loss
• MODEM — modulation and demodulation
• ACL — Average Call Length
• LUNT — Line Unit Network Termination
• HFC — Hybrid Fiber Coaxial
• LIU — Line Interface Unit
• LORAN — Long Range Aid to Navigation System
• CFNA — Call Forwarding No Answer
• EIR — Excess Information Rate
• PTT — Post Telegraph and Telecommunications
• PHY — Physical Layer
• STD — Secondary Telecom District
• ULC — Universal Line Card
• REN — Ringer Equivalence Number
• WDF — Wireless Data Forum
• PFE — Power Feed Equipment
• WDRM — Wireless Design Reference Manual
• CATI — Computer-Assisted Telephone Interviewing
• IXC — interexchange carrier
• DS-2 — Digital Signal, Level 2
• CAE — Common Application Environment
• NECA — National Exchange Carrier Association
• TEM — Transmission Electron Microscope
• NTSC — National Television Standards Committee
• TCL — Transverse Conversion Loss
• ML — maximum length
• CSL — component sublayer
• ATL — Advanced Technology Laboratory
• CRL — Computing Research Laboratory
• PT — Payload Type (ATM)
• MTS — message transport system
• DCP — Distributed Collaborative Planning
• AARQ — A-Associate Request
• ACOU — Additional Call Offering Unrestricted
• CFS — Call for Service
• TRAC — Totally Reconfigurable Analog Circuit
• FEAC — Far End Alarm and Control
• FPLMTS — Future Public Land Mobile Telecommunications System

• RU — Release Unit
• STD — Standard Deviation
• ULP — Upper Layer Protocol
• SYNC — Synchronization
• NARSAP — National Advanced Remote Sensing Application Program
• BTN — Billing Telephone Number
• ACMA — Atlantic Cable Maintenance Agreement
• LAC — Line Assignment Center
• DOR — Detailed Outage Report
• RPCU — Radio Port Control Unit
• STM — Scanning Tunneling Microscopy
• PTAM — Professional Telephone Answering Machine
• NAM — Numeric Assignment Module
• DMI — Digital Multiplex Interface
• ACRE — Authorization and Call Routing Equipment
• DFRI — Datacom Reference Frame Input
• DVCC — Digital Verification Color Code
• MIC — Management Integration Consortium
• UBT — Universal Backend Tester
• ATACS — Army Tactical Communications System
• RADARSAT — Radar Satellite
• IMPI — IP (Internet Protocol) Multimedia Private Identity
• DDS — Dataphone Digital Service (AT&T)
• NETBIOS — Network Basic Input-Output System
• SASL — Simple Authentication and Security Layer
• UPC — Usage Parameter Control
• RLS — Recursive Least Squares
• LSMS — Local Service Management System
• TJB — Telephone Junction Box
• OODBMS — Object-Oriented Database Management Systems
• PTO — U.S. Patent And Trademark Office
• LQR — Line Quality Report
• DDSD — Delay Dial Start Dial
• DTC — Department of Telecommunications and Cable
• PSLV — Polar Satellite Launch Vehicle (Indian Space Research Organization; India)
• WSN — Wireless Sensor Network
• IMTS — Improved Mobile Telephone Service
• DUNCE — Dial-Up Networking Connection Enhancement
• BUS — Business Units
• AA — Auto-Answer
• RLC — Radio Link Control
• CASE — Computer-Aided Software Engineering
• LTU — Line Terminating Unit
• DSP — Domain Specific Part
• DRTL — Dial Repeating Tie Line
• VVP — Versatile Voice Processing
• UPS — Un-interruptable Power Supply
• RLA — Received Level Average
• RSS — Received Signal Strength
• FTS — Federal Telecommunications System

• ILETS — Idaho Law Enforcement Telecommunication System
• CPS — Customer Premises System (Bellcore)
• DOV — Data-Over-Voice
• BUS — Broadcast and Unknown Server
• ATTRA — Appropriate Technology Transfer for Rural Areas
• FIC — Flight Information Center
• ALC — Automatic Line Controller
• ILETS — International Law Enforcement Telecommunications Seminar
• DLIS — Directory Listing Inquiry System
• FGDC — Federal Geographic Data Committee's
• CDPD — Cellular Digital Packet Data
• KTS — Key Telephone System
• RANAP — Radio Access Network Application Part
• UR — User Rate
• STN — Station Casinos, Inc.
• ML-PPP — Multilink Point-to-Point Protocol
• EA — Emergency Action (JOC)
• MSG — Management Steering Group
• NRZ — Nonreturn To Zero
• DISA — Direct Inward Switch Access
• SS6 — Signalling System 6
• GOSIP — Government Open System Interconnection Profile
• IRLAN — Infrared LAN
• ETSI — European Telecommunications Standards Institute
• WDS — Wireless Distribution System
• MEOS — Medium Earth Orbit Satellite
• UBL — Universal Bluetooth Link
• BBCR — BroadBand Communications Research
• IPCU — iPhone Configuration Utility
• CP — Cell Phone
• TSM — Transaction State Machine
• REA — Rural Electrification Administration (US)
• N-AMPS — Narrowband Advanced Mobile Phone System
• NSDI — National Spatial Data Infrastructure
• SAP — Service Advertising Protocol
• ONE — Other Network Entity
• CMP — Connection Management Procedures
• DTU — Date/Time Update
• CBS — Common Battery Signaling
• AADS — Ameritech Advanced Data Services
• OST — Office of Science and Technology
• AQP — Association for Quality and Participation
• WTA — Western Telecommunications Alliance
• TTIL — Team Telecom International Ltd.
• RDSS — Radio Determination Satellite Service
• SMASE — Systems Management Application Service Element
• NARC — Non-Automatic Relay Center
• DIAG — Diagnostics
• IDEN — Integrated Dispatch Enhanced Network
• HFT — Human Factors in Telecommunications

• CUG — Closed Users Group
• GTXC — Global Telephone Exchange Carrier
• AAPR — Annual Average Performance Ratio
• MIS — Management Information Service
• CCC — Credit Card Calling
• NMF — Network Management Forum
• MIS — Miscellaneous
• IS — Integrated Services
• BAC — Bar Calls
• EDGE — Enhanced Data for GSM (Global System for Mobile communication) Evolution
• CHT — Active
• WTIA — Wireless Technology Industry Association
• DQR — Directory enQuiry Restricted
• CMS — Conversational Monitor System
• MNOS — Metal-nitride-oxide Semiconductor
• VAD — Voice Activity Detection
• SYSADM — System Administrator
• EC — Echo Cancelling
• CSCC — coordinated state change control
• DPCM — Differential Pulse Code Modulator
• ASTE — Advanced Systems and Telecommunications Equipment
• PAGCH — Paging and Access Grant Channel
• QR — Quality record
• EGPRS — Enhanced General Packet Radio Service
• PPCH — Packet Paging Channel
• SMDR — station message detail recording
• T&R — Tip and Ring
• WLNP — Wireless Local Number Portability
• WWAN — wireless wide-area network
• STE — Software Test Environment
• REGEN — Regenerator
• GRX — GPRS Roaming Exchange
• CAIRO — Communications Audio Interface for Remote Operations
• SVC — Signaling Virtual Channel
• PN — Public Network
• TL — Telephone Lead
• PNA — Parallel Network Architecture
• CSA — Central Service Area
• WPOP — Wireless Point-of-Presence
• NQA — Niveau de Qualite Acceptable
• IRAC — Interdepartment Radio Advisory Committee
• SMT — station management (protocol)
• FWS — Fixed Wireless Services
• PWM — Pulse width modulation
• MO — Magneto-optic
• NAP — Network Access Point
• DAS — Distributed Antenna System
• AUSPI — Association of Unified Telecom Service Providers of India
• AGPS — Assisted Global Positioning System
• CODEC — Coder-Decoder (usually for audio/video data)

• RA — Return Alarm
• ECAN — Echo Cancellation
• LFTYR — Ley Federal de Telecomunicaciones y Radiodifusión
• RJ-11 — Registered Jack type 11 (4-wire connector)
• ISM — Interstellar Medium
• 802.X — Series of LAN standards developed by IEEE
• NAM — Number Assignment Module
• TR — Temporal Reference
• AI — Airborne Interception
• WDSL — Wireless Digital Subscriber Line
• NPSI — Network Packet Switching Interface
• CRACK — Challenge Response for Authenticated Crypto Keys
• EEHO — Either End Hop Off
• BCST — Broadcast
• LL — Lower Layer
• CCS — Common Command Set
• BMAS — Business Management System
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