2BIQ two Bits, One Quantenary
AA Allocation Area / Auto Answer
AAA Authentication, Authorization, and Accounting
AAB Automatic Answer Back
AAC Alternate Access Carrier
AAD Auditory Assistance Device
AAL ATM Adaptation Layer
AAP Alternate Access Provider
AAR Automatic Alternative Routing
ABS Alternative Billing Services
AC Alternating Current / Authentication Center / Access Connections
ACB Annoyance Call Bureau
ACD Automatic Call Distribution
ACK ACKnowledgement
ACN Access Carrier Name / Advanced Communication Network
ACNA Automated Customer / Carrier Name and Address
ACR Anonymous Call Rejection
ACP Access/Action Control Point
ACT Applied Computer Telephony
ACTA America's Carriers Telecommunications Association
ACTS Automatic Coin Telephone System / Advanced Communications Technology Satellite
ACU Automatic Calling Unit / Auto Callback Unit
ACUTA Association of College & University Telecommunications Administrators
ADAD Automatic Dialing-Announcing Device
ADD Automatic Dialing Device
ADL Additional Directory Listing
ADM Add Drop Multiplexing
ADN Advanced Digital Network
ADNS Advanced Data Network Solutions
ADPCM Adapted Differential Pulse Code Modulation
ADS Associated Directory Services
ADS-AIT Ameritech Advanced Data Services
ADSI Analog Display Services Interface
ADSL Asymmetrical Digital Subscriber Line
AF Audio Frequency
AIN Advanced Intelligent Network
AIOD Automatic Identification of Outward Dialing
AIS Automatic Intercept System / SBC Global Services, Inc
ALI Automatic Location Information / Address Location Information
ALIS Automatic Location Identification System
ALJ Administrative Law Judge
ALTS Alternate Local Transport Services
AM Amplitude Modulation / Active Monitor
AMA Automatic Message Accounting
AMACC Automatic Message Accounting Control Center
AMD Advanced Micro Devices, Inc.
AMI Alternative Mark Inversion / SBC Asset Management
AMIS Audio Messaging Interchange Specification
AMLCD Active Matrix Liquid Crystal Display
AMOS Access Mechanized Order System
AMPS Advanced Mobile Phone Service
AN Access Number
ANI Automatic Number Identification
ANS Advanced Network Systems
ANSI American National Standards Institute
AOL America OnLine
AOS Alternative Operator Services
AP Adjunct Processor / Activation Platform / Access Provider
APD Avalanche Photo Diode
API Application Programming Interface
APL Analog Private Line
APPC Advanced Program-to-Program Communications
APTOS Automated Pricing, Terminals Operations & Services
APTT Automatic Progression Trunk Testing
AQL Acceptable Quality Level
ARP Address Resolution Protocol
ARPA Advanced Research Project Agency
ARQ Automatic Repeat reQuest
ARS Automatic Route Selection
ARSB Automated Repair Service Bureau
ARU Automatic / Audio Response Unit
ASA Authorized Sales Agent
ASAI Adjunct Switch Application Interface
ASC AIN Switch Capabilities
ASCII American Standard Code for Information Interexchange
ASIC Application Specific Integrated Circuit
ASN Abstract System Notation
ASP Active Server Pages / Application Service Provider
ASR Automatic Speech Recognition / Access Service Request
ASYNCH ASYNCHronous
AT Access Tandem switch
AT&T American Telephone and Telegraph Company
ATAB Area Trunk Assignment Bureau
ATDM Asynchronous Time Division Multiplexing
ATIS Alliance for Telecommunications Industry Solution
ATM Asynchronous Transfer Mode / Automatic Teller Machine
ATN Access Tandem Network
ATS Advanced Telecommunications Services
AUI Attachment User Interface
AVD Alternate Voice Data
AVR Automatic Voltage Regulator
AVRU Automated Voice Response Unit
AWG American Wire Gauge
B Bearer channel / Bridge
B-ICI Broadband ISDN InterCarrier Interface
B-ISDN Broadband Integrated Services Digital Network
B8ZS Binary 8 bit Zero Substitution / Bipolar with 8-Zero Substitution
BACP Bandwidth allocation control protocol
BAID Billing Account ID
BAIF Billing Account Identification Facility
BAN Billing Account Number
BBN Bolt Baranek and Newman
BBS Bulletin Board System
BCD Blocked Calls Delayed
BCH Blocked Calls Held
BCI Bell Canada International
BCR Blocked Calls Released
BCS Business Communication Services
BD Bill Date
BDSA Basic Digital Special Access
BECN Backward Explicit Congestion Notification
BEMS Business Exchange Measured Service
BER Bit Error Rate
BERT Bit Error Rate Test
BES Basic Exchange Service
BG Billing Group
BHCA Busy Hour Call Attempt
BIOS Basic Input/Output System
BISYNC BInary SYNChronous (also BSC)
BIT BInary Digit
BL Basic Link
BLER BLock Error Rate
BM Broadband Modem
BN Billing Number
BNR Bell Northern Research (subsidary of BCE)
BNS Bill Number Screening
BOC Bell Operating Company
BOCP Business Optional Calling Plan
BP Binding Post
BPR Business Process Re-engineering
BPS Bits Per Second
BRADS Bellcore Rating Administrative Data System
BRI Basic Rate Interface
BRIDS Bellcore Rating Input Database System
BRSU Broadband Remote Switching Unit
BS Base Station
BSA Basic Service Arrangement
BSC Binary Synchronous Communication (also BISYNC)
BSE Basic Service Element
BTA Basic Trading Areas (Rand McNally)
BTN Billing Telephone Number
BVA Billing Validation Application
C Curb
C/N Carrier to Noise ratio
CA Communications Assistant / Collision Avoidance / Certifying Authority
CABS Carrier Access Billing System
CAC Carrier Access Code
CACD Commission Advisory and Compliance Division
CAD Computer Automated Design / Computer Aided Dispatch / Computer Aided Drafting
CADS Computer Aided Dispatch System
CAM Computer Automated Manufacturing
CAMEL Customized Applications for Mobile network Enhanced Logic
CAMA Centralized Automatic Message Accounting
CAP Competitive Access Provider
CAR Current Activity Report
CAS Centralized Attendant Service
CAT Carrier Access Tariff
CATV CAble TeleVision / Community Antenna TeleVision
CAU Cable Access Unit
CB Channel Bank / Citizens Band
CBR Constant Bit Rate
CBX Computerized Branch eXchange
CC Customer Care / Cluster Controller
CCC Customer Care Center
CCD Charge Coupled Device
CCF Common Citizen Focus
CCI Common Client Interface
CCIS Common Control/Channel Interoffice Signaling
CCIR international radio consultative committee
CCITT Consultive Committee on International Telephony and Telegraphy
CCL Common Carrier Line
CCLC Carrier Common Line Charge
CCR Customer Control Reconfiguration
CCRU Customer Care Retention Unit
CCS Common Channel Signaling / Customer Calling Services
CCS#7 Common Channel Signaling #7
CCSA Common Control Switching Arrangement
CCSN Customer Contact Services Node
CCTV Closed-Circuit TeleVision
CD Compact Disk / Collision Detection / Circuit Details
CDDI Copper Distributed Data Interface
CDMA Code Division Multiple Access
CDO Community Dial Office
CDPD Cellular Digital Packet Data
CDR Call Detail Recorder
CDT Central Daylight Time
CDU Customer Data Unit
CELL1 Cellular One
CELP Code Excited Linear Prediction
CENTREX CENTral Exchange
CEO Chief Executive Officer
CEPT Conference European on Post and Telecommunications
CESAR Customer's Enhanced System for Access Requests
CFBNA Call Forwarding for Busy and NoAnswer
CFN Call Forward Number
CGSA Cellular GeographicServing Area
CHE Cable HeadEnd
CHFP Certified Human Factors Professional
CHI Conference on Human factors In computing systems
CI Carrier Interconnection / Credit Information
CIC Carrier Identification Code
CICS Customer Information Control System
CIF Common Intermediate Format
CIR Committed Information Rate
CIT Computer Integrated Telephony
CIX Commercial Internet eXchange
CKL Circuit Location
CL Copper Loop
CL&F Common Look and Feel
CLASS Custom Local Area Signaling Services
CLC Carrier Liaison Committee / Competitive Local Carrier / Common Language Code
CLCI Common Language Code Identifier
CLEC Competitive Local Exchange Carrier
CLF Common Language Facility
CLFI Common Language Facility Identification
CLID Calling Line IDentification
CLLI Common Language Location Identifier
CLP Cell Loss Priority
CM Cable Modem
CMDB Centralized Message DataBase
CMDR Call Management Detail Records
CMDS Centralized Message Distribution System
CMIP Common Management Information Protocol
CMOS Complementary Metal-Oxide Semiconductor
CMRS Commercial Mobile Radio Services
CNA Customer Number Address
CNCA Carrier Non-Compatible Applications
CNM Customer Network Management
CNS Complementary Network Services
CO Central Office
CO-ACD Central Office Automatic Call Distributor
CO-LAN Central Office-Local Area Network
COAX COAXial
COCOT Customer Operated COin Telephone
CODEC Coder plus DECoder
COI Community Of Interest
COLA Cost Of Living Adjustment / Customer On Line Authentication
COP Customer Ordering Platform
COPT Customer Owned Public Telephone
CORBA Common Object Request Broker Architecture
COS Class Of Service / Corporation for Open Systems
COSMOS Central Office System for Mainframe Operations
COT Central Office Terminal
COTS Commercial Off-the-Shelf (stuff)
CPCN Certificate of Public Convenience and Necessity
CPE Customer Premise Equipment / Certified Professional
Ergonomist
CPI Consumer Price Index
CPM Cost Proxy Model
CPNI Customer Proprietary Number Information
CPP Calling Party Pays
CPR Core Process Re-engineering
CPS Cycles Per Second
CPU Central Processing Unit
CPUC California Public Utilities Commission
CRC Cyclical Redundancy Checking
CRIS Customer Records Information System
CRT Cathode Ray Tube
CRTC Canadian Radio-television and Telecommunications
Commission
CRU Customer Retention Unit
CS Carrier Services
CSA Custom Service Arrangement / Call path Services Architecture /
Custom Service Arrangement
CSB Customer Service Bureau
CSC Customer Service Center
CSDC Circuit Switched Digital Capability
CSDS Circuit Switched Digital Service
CSIMA Client Side Image Map Authoring
CSMA Carrier Sense Multiple Access
CSMA/CD Carrier Sense Multiple Access with Collision Detection
CSN Central / Customer Service Node
CSR Customer Service Representative / Record
CST Central Standard Time / Cooperative Scheduled Testing
CSTA Computer Supported Telecommunications Application
CSU Channel Service Unit
CT Channel Termination / Common Transport
CTI Computer Telephony Integration
CTS Clear To Send
CVN Customer Virtual Network
CVSDM Continual Variable Slope Delta Modulation
CTX CenTreX system number
CWID Call Waiting IDentification service
CWIDO Call Waiting IDentification with Options service
D Data Channel
DA Distribution Area / Directory Assistance / Digital Access
DACS Digital Access and Crossconnect System
DAL Dedicated / Direct Access Line
DAMA Demand Assigned Multiple Access
DARPA Defense Advanced Research Project Agency
DAO Directory Assistance Only
DAP Directory Access Protocol
DAS Dual Attachment Station
DAT Digital Audio Tape
dB decibel
DBAC DataBase Administration Center
DBAS DataBase Administration System
DBCS Double-Byte Character Sets
DBS Direct Broadcast Satellite
DBW Decibel per Watt
DDLMP Digital Equipment Corporation data link control
DC Direct Current
DCA Document Content Architecture
DCC Digital Control Channel
DCE Data Communications Equipment / Data Circuit-terminating
Equipment
DCO Digital Central Office
DCP Designated Carrier Plan
DCR Dynamically Controlled Routing
DCS Digital Crossconnect System
DCT Discrete Cosine Transform
DDD Direct Distance Dialing
DDS Digital Data Service / Dataphone Digital Service
DE Discard Eligibility
DEA Digital Exchange Access
DEC Digital Equipment Corporation
DES Data Encryption Standard
DHCP Dynamic Host Configuration Protocol
DIA Document Interchange Architecture
DID Direct Inward Dialing
DIDR Direct Inward Dial Number Range
DIMM Dual Inline Memory Module
DISA Direct Inward System Access
DLC Digital Loop Carrier
DLCI Data Link Connection Indicator
DLL Dynamic Link Library
DLR Design Layout Record
DM Dialogue Management
DMI Digital Multiplexed Interface / Desktop Management Interface
DMS Digital Modular Switch / Digital Multiplex System / Data
Management System
DMTS Distinguished Member of Technical Staff
DN Directory Number
DNA Data Network Address
DNCF Directory Number Call Forwarding
DNI Data Network Interface
DNIA Dialed Number Identification Service
DNIC Data Network Identification Code
DNIS Dialed Number Identification Service
DNS Domain Name System
DNSP Distributed Networked Services Platform
DOC Dynamic Overload Control
DOD Department Of Defence / Direct Outward Dialing
DOMSTATS Domestic Satellite Carriers
DOS Disk Operating System / Domestic Operator Service
DOV Data Over Voice
DOW Day Of Week
DP Data Processing / Dial Pulse
DPBX Digital Private Branch eXchange
DPE Digital Parity Error
DPG Digital Pair Gain
DQDB Distributed Queue Dual Bus
DR Digit Receiver
DRA Division of Ratepayer Advocates
DRAM Dynamic Random Access Memory
DRP Dispute Resolution Procedure
DS Data Services / Directory Services
DS-0 Digital Signal level 0
DS-1 Digital Signal level 1
DS-2 Digital Signal level 2
DS-3 Digital Signal level 3
DSA Directory Systems Agent / Digital Signature Algorithm
DSC Digital Switch Corporation
DSE Data Switching Exchange
DSI Digital Speech Interpolation
DSL Digital Subscriber Line
DSLAM Digital Subscriber Line Access Multiplexer
DSMA/CD Digital Sense Multiple Access with Collision Detection
DSN Digital Switched Network
DSP Directory Service Protocol / Digital Signal Processor
DSR Data Set Ready
DSS Decision Support System
DSU Digital Service Unit / Data Service Unit
DSX termination hardware for DS-1 and DS-3's / Digital Service
crossconnect frame
DT Dedicated Transport
DTD Document Type Declaration
DTE Data Terminal Equipment
DTMF Dual Tone Multi Frequency
DTR Data Terminal ready
DTS Data Terminal Set
DUA Directory User Agent
DVM Digital Volt Meter / Data Voice Multiplexer
DXI Data eXchange Interface
E&M Ear and Mouth
EAD Expedited Application Docket
EADAS Engineering and Administration Data Acquisition System
EAOSS Exchange Access Operator Service Signaling
EARS Easy Access Request System
EAS Extended Area Service / Equal Access Signaling
EBAT Electronic Bill Analysis Tool
EBCDIC Extended Binary Coded Decimal Interchange Code
EBS Electronic Business Sets
ECC Error Checking/Correction Code
ECN Electronic Communication Network
ECSA Exchange Carriers Standards Association
EDGE Enhanced Data rate for GSM Evolution
EDI Electronic Data Interexchange
EDIFACT EDI for Administration, Commerce, and Transportation
EEO Equal Employment Opportunities
EF Entrace Facility
EFS Error Free Seconds
EGA Enhanced Graphics Adaptor
EGP Exterior Gateway Protocol
EIDE Enhanced Integrated Device Electronics
EIR Equipment Identity Register
EIRP Effective Isotropic Radiated Power
EKTS Electronic Key Telephone Service
EMA Electronic Mail Association
EMF Electro-Magnetic Force
EMI Electro-Magnetic Interference
EMR Exchange Message Record
ENFIA Exchange Network Facilities for Interstate Access
EO End Office
EOF End Of File
EOL End Of Line
EPS Enhanced Paging Service
EPSCS Enhanced Private Switched Communications Service
ER Equipment Room
ERD Enhanced Repeat Dial service
ERL Echo Return Loss
ES Earth Station
ESF Extended Super Frame
ESN Electronic Serial Number / Emergency Service Number /
Electronic Switched Network
ESP Enhanced Service Providers
ESS Electronic Switching System
ETC Enhanced Throughput Cellular / Eligible Telecommunications
Carrier
ETE End-To-End
ETF Electronic Telephone Features
ETN Electronic Tandem Network
EUCL End User Common Line
EUM End User Migration
EXCO EXchange Central Office
FABS Flexible Automated Billing System
FACS Facility Assignment and Control System
FAQ Frequently Asked Question
FAT File Allocation Table
FAX facsimile
FCC Federal Communications Commission
FCS Frame Check Sequence
FDDI Fiber Distributed Data Interface
FDF Fiber Distribution Frame
FDL Facility Data Link
FDM Frequency Division Multiplexer
FDMA Frequency Division Multiple Access
FEA Federal Executive Agencies
FEAL Fast Encryption ALgorithm
FEC Forward Error Correction
FECN Forward Explicit Congestion Notification
FEP Front End Processor
FEPS Facility and Equipment Planning System
FEX Foreign EXchange
FFOL FDDI Follow-On LANs
FG Feature Group
FGD Feature Group D (protocol to transmit MIN and PIC for cellular)
FH Fiber Hub
FID Feature Identification Code / Field IDentifier
FIFO First In First Out
FITL Fiber In The Loop
FLM Fiber Loop Multiplexer
FM Frequency Modulation
FN Fiber Node
FNPRM Further Notice of Proposed Rulemaking
FNS Feature Node Services
FO Fiber Optics
FOC Firm Order Confirmation
FOD Fax On Demand
FOT Fiber Optic Terminal
FOTS Fiber Optics Transmission System
FPP Flexible Pricing Plan
FPS Fast Packet Switching / Framing Pattern Sequence
FPU Floating Point Unit
FR Frame Relay
FRA Fixed Radio Access
FRAD Frame Relay Access Device
FRD Feature Request Document
FSA Fiber Serving Area
FSK Frequency Shift Keying
FTA Federal Telecommunications Act of 1996
FTAM File Transfer Access & Management
FTP File Transfer Protocol
FTTC Fiber To The Curb
FTTH Fiber To The Home
FUT Friendly User Trial
FX Foreign Exchange
G Giga-
G/T Gain to Thermal noise
GAAP Generally Accepted Accounting Principles
GAP Generic Access Parameter
GBPS / GB/s GigaBits Per Second
GCD Graphic Codepoint Definition
GEO Geostationary Earth Orbit
GFC Generic Flow Control
GGSN Gateway GPRS Support Nodes
GHZ GigaHertZ
GIF Graphic Interface Format
GIN GSM Information Network
GIS Geographic Information Systems
GK Gatekeeper
GMS Geostationary Meteorological Satellite
GMT Greenwich Mean Team
GO General Order
GOS Grade Of Service
GPRS Generalized Packet Radio Service/System
GPS Global Position Satellite/System
GS Gate Server
GSM Global Standard/System for Mobile telecommunications
GSP Global Service Provider
GTT Global Title Translations
GUI Graphics User Interface
GW Gateway
H Header
HCDS High Capacity Data Services
HDLC High level Data Link Control
HDML Handheld Device Markup Language
HDR frame HeaDeR
HDSL High bit rate Digital Subscriber Line
HDT Host Digital Terminal
HDTV High Definition TeleVision
HE Head End
HEC Header Error Control
HF Human Factors
HF/E Human Factors / Ergonomics
HFC Hybrid Fiber Coax
HFES Human Factors and Ergonomics Society
HICAP High Capacity Digital Services
HID Human Interface Device
HIPPI HIgh performance Parallel Processing Interface
HLFD High Level Functional Design
HLR Home Location Register
HMI Human-Machine Interface
HPC High Performance Computing
HSCSD High Speed Circuit Switched Data
HTML HyperText Markup Language
HTTP HyperText Transmission Protocol
HTTPS HTTP Secure
Hz Hertz
I&R Installation and Repair
I/O Input and Output
IAM Initial Address Message
IBDN Integrated Building Distrubution Network
IC Integrated Circuit / Independent Company / Installation Center /
Interconnection Charge / InterLATA Carrier
ICANN Internet Corporation for Assigned Names and Numbers
ICB Individual Case Basis
ICCF Industry Carriers Compatibility Forum
ICID Internet Caller IDentification service / Interexchange Carrier ID
ICLID Incoming Caller Line IDentification
ICMP Internet Control Message Protocol
ICSC Interexchange Carrier Service Center
ICU ISA Configuration Utility
ICSWE Interexchange Carrier Serving Wire Center
IDC Internet Data Center
IDE Integrated Device Electronics
IDEA International Data Encryption Algorithm
IDF Intermediate Distributing Frame
IDLC Integrated Digital Loop Carrier
IDS Intrusion Detection System
IEA International Ergonomics Association
IEC InterExchange Carrier
IEEE Institute of Electrical & Electronics Engineers
IETF Internet Engineering Task Force
IF Intermediate Frequency
IFR Item for Resolution
IIHSO Intercompany Interconnection Held Service Order
IISO Intercompany Interconnection Service Order
IIT Interactive Information Technology
ILEC Incumbent Local Exchange Carrier / Independent Local
Exchange Carrier
ILP IntraLATA Presubscription
IM Intensity Modulation / Instant Messaging
IMAP4 Internet Message Access Protocol 4
IMG Industry Markets Group
IML Incoming Matching Loss
IMS Interface Management System
IMT Inter-Machine Trunk
IMTS Improved Mobile Telephone Service
IN Intelligent Network / Interface Network
INC Industry Numbering Committee
INMARSAT INternational MARitime Satellite Service
INP Interim Number Portability
INPA Interchangeable Numbering Plan Area
INPG Industry Number Plan Guide
INS Information Network System
INWATS INward Wide Area Telephone Service
IP Intelligent Peripheral / Internet Protocol / Information Provider
IPSS Inter-Processor Signaling System
IR Infra-Red
IRD Implementation Rate Design
IRQ Interrupt ReQuest
ISA Industry Standard Architecture
ISC Industry Service Center
ISCP Integrated Service Control Point
ISDN Integrated Services Digital Network
ISM Industrial, Scientific, Medical
ISN Information Systems Network
ISO International Standards Organization
ISP Internet Service Provider / Information Service Provider
ISR Interconnection Service Request
ISSN Integrated Special Services Network
ISU Iridium Subscriber Unit
ISUP ISDN Services User Part
IT Information Technology
ITG Interswitch Trunk Group
ITGS Intelligent Traffic Guidance Systems
ITU International Telecommunications Union
ITV Interactive TeleVision
IV Interactive Video
IVS Interactive Video System
IVTTA Intelligent Vehicle and Transportation Technical Area
IW Inside Wire
IX IntereXchange
IXC IntereXchange Carrier
IXVG interexchange voice grade channel
JPEG Joint Photographic Experts Group
K Kilo-
KBPS / KB/s KiloBits Per Second
KCPS KiloCycles Per Second
KHZ KiloHertZ
KM KiloMeter
KP Key Pulse
KTS Key Telephone System
KWH KiloWatt Hour
LAC Loop Assignment Center
LADT Local Area Data Transport
LAMA Local Automatic Message Accounting
LAN Local Area Network
LAP-B Link Access Protocol Balanced
LAPD Distributed Link Access Procedure
LAPS Local Access ProcedureS
LARG LIDB Access Routing Guide
LASS Local Access Signaling Services
LATA Local Access and Transport Area
LC Local Competition
LCC Line Class Code
LCD Liquid Crystal Diode/Display
LCR Least Cost Routing
LD Long Distance
LDAP Lightweight Directory Access Protocol
LDI Long Distance Indicator
LDS Long Distance Switching
LEC Local Exchange Carrier / LAN Emulation Client
LED Light Emitting Diode
LEO Low Earth Orbit
LEOS Low Earth Orbiting Satellite
LERG Local Exchange Routing Guide
LES LAN Emulation Server
LF Loop Feeder
LFACS Loop Facility Assignment Control System
LI Local Interconnection
LIDB Line Information DataBase
LIFO Last In First Out
LISA Local Interconnection Service Arrangement
LISC Local Interconnection Service Center
LIT Line Insulation Test
LLC Logical Link Control / Limited Liability Company
LMDS Local Multipoint Distribution Service
LMOS Loop Maintenance Operations System
LMS Local Measured Service
LMTS Lead Member of Technical Staff
LNP Local Number Portability
LOC Local Operations Center
LPC Linear Predictive Coding
LPIC Local Primary Interexchange Carrier
LSB Least Significant Bit
LRC Longitudinal Redundancy Check
LRN Local Routing Number
LSC Local Service Center
LSNE Local Switching Network Element
LSNP Local Switching with Number Portability
LSO Local Serving Office
LSP Local Service Provider
LSR Local Service Request
LT Local Transport
LTD Local Test Desk
LU Logical Unit
M Modem / Mega-
M&P Methods & Procedures
MA Maintenance Administrator
MAC Media Access Control
MADN Multiple Appearance Directory Number
MAN Metropolitan Area Network
MAP Manufacturing Automation Protocol
MAP/TOP Manufacturing Automation Protocol/Technical and Office Protocol
MAPI Mail Application Programming Interface
MAU Multistation Access Unit
MBPS / MB/s Mega Bits Per Second
MBS Mobile Broadband Systems
MC Message Center / Maintenance Center
MCC Microelectronics & Computer technology Co.
MCGA Multi-Color Graphics Array
MCU Multipoint Control Unit / Master Control Unit
MCVD Modified Chemical Vapor Deposit
MDBS Mobile DataBase Station
MDF Main Distribution Frame
MDIS Mobile Data Intermediate Station
MDNS Message Delivery to NonSubscriber
MDR Message Detail Recording
MDS Multipoint Distribution Service
MDT Mobile Data Terminal
MDU Multiple Dwelling Unit
MEO Medium Earth Orbit
MF Multi-Frequency / Main Frame
MFJ Modified Final Judgment
MHZ MegaHertZ
MHS Message Handling System
MIB Management Information Base
MID Message IDentifier
MIDI Musical Instrument Digital Interface
MIDP Mobile Information Device Profile
MIF Management Information Format
MIME Multipurpose Internet Mail Extentions
MIN Mobil Identification Number
MIPS Millions of Instructions Per Second
MLAC Mechanized Loop Assignment Center
MLHG Multi-Line Hunt Group
MLN Main Listed Number
MM Multi Media / Multi Mode
MMDS Multichannel Multipoint Distribution Service
MODEM MOdulator / DEModulator
MOM Manager of Managers
MOU Minutes Of Use
MPB Meet Point Billing
MPEG Moving Picture Experts Group
MPOP Minimum Point of Penetration (wire)
MS Management System / MilliSecond / Mobile Station
MSA Management System Architecture / Metropolitan Serving Area /
Metropolitan Statistical Area
MSAG Master Street Address Guide
MSC Mobile Switching Center
MSD Marketing Service Description / Musculo-Skeletal Disorder
MSS Mobile Satellite Services
MT&T Maritime Telegraph and Telephone
MTA Message Transport Agent / Major Trading Areas (Rand McNally)
MTBF Mean Time Between Failures
MTF Modulation Transfer Function
MTP Message Transfer Port
MTS Member of Technical Staff / Message Telecommunications
Service / Manitoba Telephone System / Message Toll Service
MTSO Mobil Telephone Switching Office
MTTR Mean Time To Repair
MTU Maximum Transfer Unit
MPEG Moving Picture Experts Group
MUX MUltipleXer
MVIP Multivendor Integration Protocol
MWI Message Waiting Indicator
NAA Number Assignment Administration
NAC Network Administration Center / Number Assignment Center
NANC North American Numbering Council
NANP North American Number Plan
NAP Network Access Point
NAPLS North American Presentation Level protocol Syntax
NAR Network Access Restriction
NARUC National Association of Regulatory Utilities Commissions
NAU Network Access/Addressable Unit
NCP Network Control Point/Program
NCSA National Center for Supercomputing Applications
NCTE Network Channel Termination Equipment
NDIS Network Device Interface Specification
NE Network Element
NECA National Exchange Carriers Association
NENA National Emergency Number Association
NEXT Near End cross Talk
NFAS NonFacility Associated Signaling
NFS Network File System
NI Network Interconnect
NIC Network Interface Card / Network Information Center / Network
Interconnection Charge
NID Network Interface Device
NII National Information Infrastructure
NIST National Institutes of Standards and Technology (old National
Bureau of Standards)
NIUF N.A. ISDN User Forum
NLM Netware Loadable Module
NMA Network Monitoring and Analysis
NMC Network Management Center
NMCC Network Management Control Center
NMS Network Management System
NNA Network Node Address
NNI Network Node Interface / Network to Network Interface
NNTP Network News Transfer Protocol
NPA Numbering Plan Area
NPAC Number Portability and Administrative Center
NPAS Network Portability Access Service
NPD Non-Payment Disconnect
NPRM Notice of Proposed RuleMaking
NRC Non Recurring Charge
NREN National Research & Education Network
NRF New Regulatory Framework
NRS Number Referral Service
NRZ NonReturn to Zero
NRZI NonReturn to Zero Inverted
NSF National Science Foundation
NSFNET National Science Foundation NETwork
NSP Network Services Protocol
NT Network Termination
NT1 Network Terminal 1 / Network Termination 1
NT2 Network Termination 2
NTG Network interface Trunk Group
NTN Network Terminal Number / New Telephone Number
NTSC National Television System Committee
NTW Network Terminating Wire
NUI Network User Identifier
NVT Network Validation Test
NWP National White Pages
NWPD National White Page Directory
NXX telephone prefix (npa) NXX-xxxx
NYNEX New York, New England eXchange
O&M Operation and Maintenance
OA Operator Assistance
OAI Open Access Interconnection
OAM Operation, Administration and Maintenance
OAM&P Operation, Administration, Maintenance & Provisioning
OANAD Open Access Network Architecture Development
OBF Ordering & Billing Form
OC Optical Carrier / Operating Company
OC3 Optical Carrier 3
OCC Other Common Carrier / Outgoing Call Control service
OC&C Other Charges & Credits
OCP Optional Calling Plan
OCR Optical Character Recognition
ODBC Open Data Base Connectivity
OE Office Equipment
OEM Original Equipment Manufacturer
OHD Off-Hook Delay trigger
OLE Object Linking and Embedding
OLTM Optical Line Termination Multiplexer
ONA Open Network Architecture / Order Number Administration
ONI Operator Number Identification
ONU Optical Network Unit
OO Object-Oriented
OODBMS Object Oriented DabaBase Management System
OPX Off Premise eXtension
ORT Operational Readiness Testing
OS Operating System
OSA Open System Architecture
OSI Open Systems Interconnection
OSP Operator Service Provider / OutSide Plant
OSO Origination Screening Office
OSP Operator Service Provider
OSPF Open Shortest Path First
OSS Operational Support Systems
OTIS Optical Transport Interconnection Service
P/AR Peak to Average Ratio
PA PreArbitrated
PABX Private Automatic Branch eXchange
PAD Packet Assembly-Disassembly
PAL Phase Alternate Line
PAM Pulse Amplitude Modulation
PAMR Public Access Mobile Radio
PAR Prompted Auto-Redial service
PASP Public Service Answering Point
PBX Private Branch eXchange
PC Personal Computer
PCI Peripheral Component Interconnect
PCM Pulse Code Modulation
PCN Personal Communications Network
PCS Personal Communication Service / Personal Communication
System
PD Premier Dialing
PDA Personal Digital Assistant
PDC Power Distribution Center
PDF Portable Document Format]
PDN Public Data Network
PDU Protocol Data Unit
PI Process Improvement
PIC Primary Interexchange Carrier
PICC Primary Interexchange Carrier Charge
PIG Proprietary Information Guidelines (legal document
classification)
PIM Product Integration Manager
PIN Personal Identification Number
PIT Process Integration Testing
PKI Public Key software Infrastructure
PLP Presentation Level Protocol
PLU Percentage Local Usage
PM Phase Modulation / Privacy Manager service
PMTS Principal Member of Technical Staff
PNS Packet Switching Node
POF Pending Order File
POI Point of Interconnection
POP Point Of Presence
POP3 Post Office Protocol 3
POS Point Of Sale
POT Point of Termination
POTS Plain Old Telephone Service
PPD Project Profile Database / Preferred Payment Date
PPP Point to Point Protocol
PPSN Public Packet Switched Network
PRD Prompted Repeat Dial service
PREMIS Premises Information System
PRI Primary Rate Interface
PRS Personalized Response System
PS Packet Switch
PSAP Primary Safety Answering Point
PSD Product Specification Document
PSDS Public Switched Data Services
PSI Performance Systems International
PSK Phase Shift Keying
PSTN Public Switched Telephone Network
PT Payload Type
PTM Packet Transfer Mode
PTN Personal Telephone Number
P2P Peer-To-Peer
PTT Post Telephone & Telegraph admin
PU Physical Unit
PUC Public Utilities Commission
PVC Permanent Virtual Connection / Permanent Virtual Circuit
PVN Private Virtual Network
PVT Product Validation Testing
PZN PersonaliZed telephone Number
QA Quality Assurance / Queue Arbitrated
QAM Quadature Amplitude Modulation
QBE Query By Example
QDT Quick Dial Tone
QoR Query on Release / Query on Response
QoS Quality of Service
QPSX Queued Packet and Sychronous eXchange
R Router
RACF Remote Access to Call Forwarding
RADN Remote Access Dialing Number
RAID Redundant Array of Inexpensive/ Independent Disks
RAL Resale Access Line
RAM Random Access Memory
RAO Revenue / Regional Accounting Office
RBOC Regional Bell Operating Company
RC Ringing Circuit / Radio Control / Recurring Charges
RCA Radio Corporation of America
RCC Radio Common Carrier
RCF Remote Call Forwarding
RCI Rate Center Inconsistency
RCMAC Recent Change Memory Administration Center
RCRMS Revenue Collection Risk Management System
RCU Remote Cell Unit
RD Receive Data
RDAC Remote Digital Access Center
RDBMS Relational DabaBase Management System
RDC Regional Data Center
RDU Remote Distribution Unit
REC RECeiver
RF Radio Frequency
RFA Request For Action
RFC Request For Comment
RFI Request For Information
RFP Request For Proposal
RFQ Request For Quote
RI Ring Indicator / Route Index
RIP Routing Information Protocol
RISC Reduced Instruction Set Computer
RMATS Remote Maintenance And Testing System
RMON Remote Monitoring
RMS Root Mean Square
RN Reference Noise
ROCP Residence Optional Calling Plan
ROI Return On Investment
ROM Read Only Memory
ROTL Remote Office Test Line
ROW Right Of Way
RPC Remote Procedure Call
RPCU Radio Port Control Unit
RPM Resource Prioritization Manager
RRUD Residence Resale Usage Discounts
RS1 Radiofone Services, LLC
RS-232C Recommended Standard-232C serial communications standard
RSA Rural Serving / Statistical Area
RSAP Resale Service Area Plan
RSL Received Signal Level
RSM Remote Switching Module
RSP Repair Service Bureau
RSS Remote Switching System
RSU Remote Switching Unit
RT Remote Terminal
RTA Remote Trunk Arrangement
RTAD Remote Test Access Data
RTF Rich Text Format
RTP Realtime Transport Protocol
RTS Request To Send / Referral Tracking System / Repair Transfer
Service
S Signal splitter
S&LT Speech and Language Technology
SA Service Author / Special Access
SA/SP Smart Access Shopping Protocol
SAC Satellite Access Center / Service Access Codes / Special Access
Code
SAD Service Address Directory
SAG Street Address Guide
SAI Serving Area Interface
SAP Special Access POTS service
SAR Segmentation and Reassembly
SAS Single Attachment Station
SATD Street Address Telephone Directory
SB Summary Billing
SBI Subscriber Browser Interface
SBS Satellite Business Systems
SC Service Creator
SCA Selective Call Acceptance / Subsidiary Carrier Authorization
SCAI Switch-to-Computer Application Interface
SCC Special Common Carrier / Sattelite Communications Control /
Service Control Center / Switching Control Center
SCCS Switching Control Center System
SCP Service Control Point
SCSA Signal Computing System Architecture
SCSI Small Computer Systems Interface
SD Speaker Dependent
SDH Synchronous Digital Hierarchy
SDK Software Development Kit
SDLC Synchronous Data Link Control
SDN Software Defined Network
SDN Software Defined Network Control Center
SDR Speaker Dependent Recognition
SDRAM Synchronous Dynamic Random Access Memory
SDS Short Data Service / Switched Digital Services
S&E Service & Equipment
SECAM Sequential Coleur Avec Memoire
SET Secure Electronic Transaction
SF Super Frame / Signal Frequency
SGML Standard Generalized Markup Language
SGSN Serving GPRS Support Node
SI Speaker Independent
SICDR Speaker Independent Connected Digit Recognition
SID System Identification
SIM Subscriber Information Module
SIMM Single Inline Memory Module
SIP SMDS Inteface Protocol
SIR Speaker Independent Recognition / Sustained Information Rate /
Secure Internet Roaming
SIT Special Identification Tones / System Intergration Testing
SIV Speaker Identity Verification
SLA Service Level Agreement
SLC Subscriber Loop Carrier / Subscriber Line Charge
SLEE Service Logic Execution Environment
SLIP Serial Line Internet Protocol / Synchronous Line Interface
Protocol
SLP Service Logic Program
SLS Spoken Language Systems
SM Single Mode
SMD-PP Short Message Delivery - Point to Point
SMDI Simple Message Desk Interface
SMDR Station Message Detail Recording
SMDS Switched Multimegabit Data Service
SME Short Message Entity / Subject Matter Expert
SMI Structure of Management Information
SMIL Synchronized Multimedia Integration Language
SMR Special Mobile Radio
SMS Service Management System / Speech Mail System / Short
Message Services
SMSC Short Message Service Center
SMSA Standard Metropolitan Statistical Area
SMTP Simple Mail Transfer Protocol
SMTS Senior Member of Technical Staff
SN Service Node / Serial Number
SN&M Service Negotiation and Management
SNA Systems Network Architecture
SNET Southern New England Telephone Company
SNMP Simple Network Management/Monitoring Protocol
SNR Signal to Noise Ratio / Single Number Reach
SO Service Order
SOAC Service Order Analysis & Control
SOFE Service Order Front End system
SOH Start Of Header
SOHO Small Office - Home Office
SONET Synchronous Operating/Optical NETwork
SORD Service Order Retrieval and Distribution system
SP Switching Point / Signaling Point / Service Provider
SPC Switched Permanent Circuits / Stored Program Control / Statistical Process Control
S-PCN Satellite Personal Communication Networks
SPCS Stored Program Controlled Switch
SPI Software Plug In
SPIN Service Provider Identification Number
SPLNP Service Provider Local Number Portability
SPMP Service Provisioning Measurement Plan
SPN Service Provider Number
SPOC Single Point of Contact
SPT Speech Processing and Telephony (telephone front-end)
SQL Structured Query Language
SR Selective Routing / Service Request
SRL Singing Return Loss
SS7 Signaling System #7
SSB Signal Side Band
SSCP System Service Control Point
SSH Secure SHell
SSI Single System Imaging
SSL Secure Socket Layer
SSN Switched Services Network
SSP Service Switching Point / Port
SSTDMA Spacecraft Switched Time Division Multiple Access
ST end of pulsing signal (Stop) / Subscribers Terminal
STM Synchronous Transfer Mode / SONET Terminal Multiplexer
STP Signal Transfer Point / Strategic Technical Project
STS Synchronous Transport Signal
STX Start of TeXt
SVC Switched Virtual Circuit
SVD Simultaneous Voice Data
SVGA Super Video Graphics Array
SWAP Shared Wireless Access Protocol
SWC Switching Wire Center / Serving Wire Center
SXS Step-by-step Switch
SYNCH SYNCHronous
T-1 DS-1 digital system
TA Terminal Adapter
TACACS+ Terminal Access Controller Access Control System Plus
TACD Telephone Area Code Directory
TACS Total Access Communications System
TAG Trunk Assignment Group
TAN Technician Access Network
TAO Telephony Access Object
TAPI (Microsoft's) Telephone/Telephony Application Programming Interface
TAT Terminating Attempt Trigger / TransATlantic
TBD To Be Determined
TBE Toll Billing Exception
TC Telecommunications Closet
TCAM Telecommunications Communication Access Method
TCAP Transaction Capabilities Application Part
TCI Telephone Company Identification
TCM Time Compression Multiplexing / Trellis Coded Modulation
TCP Transfer Call Period
TCP/IP Transmission Control Protocol/Internet Protocol
TD Transmit Data
TDC Terrestial Data Circuit
TDI Tie Down Information
TDM Time Division Multiplexing / Technical Development Manager
TDMA Time Division Multiple Access
TDMS Time Division Multiplexing System
TDOA Time Difference Of Arrival
TDR Time Domain Reflectometer
TE1 Terminal Equipment type 2
TE2 Terminal Equipment type 1
TELNET terminal emulation protocol & application
TEMPEST Transient ElectroMagnetic Pulse Emanation STandard
TFN Toll Free Number
TFS Toll Free Service
TFT Thin Film Transistor
TG Technical Group / Trunk Group
THT Token Holding Timer
TIA Telecommunications Industry Advisory
TIE Time Interval Error
TIFF Tagged-Image File Format
TIRKS Trunk Integrated Records Keeping System
TJ Times Journal Publishing Company
TLD Transmission Level Point
TMGB Telecommunications Main Grounding Busbar
TN Telephone Number
TNA Telephone Number Assignment
TOD Time Of Day
TOPS Traffic Operator Position System
TP Toll Prefix
TPC Terminating Point Code
TPCC TransPort Cross Connect
TPG Terminating Point Group
TQM Total Quality Management
TR TransmitteR / Technical Requirements
TRA Traffic Routing Administration
TRD Technical Requirements Document
TRS Telecommunications Relay Services
TRT Token Rotation Time
TS Terminal Server / Tandem Switching
TSAPI (Novell's) Telephone/Telephony Application Programming Interface
TSG Technology Services Group
TSO Terminating Screening Office
TSP Tandem Switch Provider
TSPS Traffic Service Position System
TSR Terminate and Stay Resident programs
TSS Trunk Servicing System
TST Tandem Switched Transport
TT Touch Tone / Text Telephone (for the deaf) / Transport Termination
TTC Tandem Transit Charge
TTP Trusted Third Party
TTRT Target Token Rotation Time
TTS Text To Speech
TUI Telephone User Interface
TUR Traffic Usage Recorder
TURN Toward Utility Rate Normalization
UA User Agent
UCAN Utility Consumers Action Network
UCD User-Centered Design / Uniform Call Distribution
UDLC Univac Data Link Control
UDP User Datagram Protocol
UHF Ultra High Frequency
UI User Interface
ULTS Universal Lifeline Telephone Service
UM Unified Messaging
UMTS Universal Mobile Telecommunications System
UNC Universal Naming Convention
UNI User Network Interface
UPC Usage Parameter Control
UPS Uninterruptable Power Supply / United Parcel Service
URI Universal Resource Identifier
URL Uniform Resource Locator
URN Uniform Resource Name
USB Universal Serial Bus
USO Universal Service Order
USOC Universal Service Offering/Order Code
USP Usage Sensitive Pricing
USTA United States Telecommunications Association
UTP Unshielded Twisted Pair
UTS Unbundled Tandem Switching
VAD Voice Activated Dialing
VAN Value Added Network
VANC Voice Activated Network Control
VANS Value Added Network Service
VAPD Voice Activated Premier Dialing
VBR Variable Bit Rate
VC Virtual Channel / Virtual Connection
VCI Virtual Circuit/Channel Identifier
VCR Video Cassette Recorder
VCS Voice Control Systems
VDM Voice Data Mux
VDT Video Dial Tone / Video/Visual Display Terminal
VDU Visual Display Unit
VE Virtual Environment
VF Voice Frequency
VFG Virtual Facility Group
VFL Voice Frequency Line
VGA Video Graphics Array
VHE Virtual Home Environment
VHF Very High Frequency
VIN Virtual Intelligent Network
VLAN Virtual Local Area Network
VLR Visiting Location Register
VM Virtual Memory
VMI Visual Message Indicator
VMR Virtual Media Resource
VMS Virtual Memory System
VNL Via Net Loss
VOD Video On Demand
VOIP Voice Over Internet Protocols
VON Voice On the 'Net
VP Virtual Path / Vice President
VPC Voice Processing Co. / Virtual Permanent Circuit / Virtual Private Circuit
VPI Virtual Path Identifier
VPIM Voice Profile for Internet Mail
VPN Virtual Private Network
VPO Vantage Point Operations
VQN Variable Quantizing Network
VR Voice Response / Virtual Reality
VRAM Video Random Access Memory
VRML Virtual Reality Modeling Language
VRU Voice Response Unit
VSAT Very Small Aperture Terminal
VSB/AM Visual Side Band Aperture Modulation
VSP Video Service Provider
VTAM Virtual Terminal Access Method
VU Volume Unit
W3C World Wide Web Consortium
WA Work Area
WAE WAP Application Environment
WAIS Wide Area Information Service
WAL WATS Access Line
WAN Wide Area Network
WAP Wireless Application Protocol
WATS Wide Area Telecommunications Service
WC Wire Center
W-CDMA Wideband-CDMA
WD Wideband Data/Digital
WDM Wavelength Division Multiplexing
WFA Work Force and Administration
WIN Wireless Intelligent Network
WINTEL Windows Intel
WISP WAP Internet Service Provider
WLL Wireless Local Loop
WM Wireline Modem
WML Wireless Markup Language
WP White Pages
WS Work Station / Wireless Service
WSC Wireless Subscriber Controller
WSL Wireless Session Layer
WSOP Working Service On Premises
WSP Wholesale Service Provider / Wireless Service Provider
WTA Wireless Telephony Application
WTLS Wireless Transport Layer Security
WTN Working Telephone Number
WTP Wireless Transport Protocol
WUI Web User Interface
WWW World Wide Web
XI X.25 Interconnection
XBAR cross BAR switch
XGA eXtended Graphics Array
XML Extensible Markup Language
XMS Extended Memory Specification
XPD Cross Polarization Discrimination
YP Yellow Pages
ZBTS Zero Byte Time Slot
ZUM Zone Usage Measurement