\\ More than 3500 Telecom abbreviations maintained by Ioan (Nini) Indreias // 1 A B C D E F G H I J K L M N O P Q R S T U V W X Y Small version 1G The first generation of analogue mobile phone technologies (AMPS, TACS and NMT) 2.5G The enhancement of GSM which includes technologies such as GPRS 2BIQ Two Bits, One Quantenary 2DRMS 2-Dimensional Root Mean Square 2G The second generation of digital mobile phone technologies (GSM, CDMA IS-95 and D-AMPS IS-136) 3G The third generation of mobile phone technologies covered by the ITU IMT-2000 family 3GPP The 3rd Generation Partnership Project 3GPP Third Generation Partnership Project 8PSK Octantal Phase Shift Keying A-bis Interface between the BSC and BTS in a GSM network A-TDMA Advanced Time Division Multiple Access A51/2/3/8X Encryption algorithms for GSM networks AA Administrative Authority AA Allocation Area AA Auto Answer AAA Authentication, Authorisation, and Accounting (OAM) AAB Automatic Answer Back AAC Alternate Access Carrier AAD Auditory Assistance Device AAL ATM Adaptation Layer AAP Alternate Access Provider AAR Automatic Alternate Routing AAR Automatic Alternative Routing AARP AppleTalk Address Resolution Protocol AAV Alternate Access Vendors AB Access Burst ABEND Abnormal end ABM Accunet Bandwidth Manager ABM Asynchronous Balanced Mode (HDLC) ABME ABM Extended ABR Area Border Router ABR Available Bit Rate (ATM) ABRD Automatic Baud Rate Detection ABS Alternate Billing Service ABS Alternative Billing Services ABS Application Bridge Server ABS Average Busy Stream ABSBH Average Busy Season Busy Hour (telephony) AC Access Connections AC Access Control (Token Ring, FDDI) AC Alternating Current AC Authentication Center ACA Asyncronous Communication Adapter ACB Annoyance Call Bureau ACC ANSI C++ Compiler ACCH Associated Control Channel (GSM) ACD Automatic Call Distribution/Distributor ACELP Algebraic Code Excited Linear Prediction ACF Access Control Field (DQDB) ACF Access Coordination Function ACF Advanced Communication(s) Function ACFA Advanced CMOS Frame Aligner ACG Automatic Call Gapping ACG Automatic Code Gapping ACI Answer Controller Interface ACIA Asyncronous Communications Interface Adapter ACK ACKnowledgement ACK Acknowledgment (DDCMP, BISYNC) ACL Access Control List ACM Address Complete Message (SS7) ACN Access Carrier Name ACN Advanced Communication Network ACN Application Context Name ACNA Automated Customer/Carrier Name and Address ACO Automatic Cut Off ACP Access/Action Control Point ACPI Advanced Configuration and Power Interface ACR Allowed Cell Rate ACR Anonymous Call Rejection ACR Automatic Call Routing ACS Asynchronous Communications Server ACSE Association Control Service Element (Application Layer) ACT Applied Computer Telephony ACTA America's Carriers Telecommunications Association ACTE Approvals Committee for Terminal Equipment ACTLU Activate Logical Unit (SNA) ACTPU Activate Physical Unit (SNA) ACTS Advanced Communications Technologies and Services ACTS Advanced Communications Technology Satellite ACTS Automatic Coin Telephone System ACU Alarm Control Unit ACU Antenna Combining Unit ACU Array Configuration Utility ACU Auto Callback Unit ACU Automatic Calling Unit ACUTA Association of College & University Telecommunications Administrators AD Administrative Domain ADAD Automatic Dialing-Announcing Device ADC Analog to Digital Converter ADCCP Advanced Data Communications Control Protocol (ANSI) ADD Automatic Dialing Device ADF Adapter Description File ADL Additional Directory Listing ADM Add/Drop Multiplexer ADMA Advanced DMA controller ADMD Administration Management Domain ADN Advanced Digital Network ADNS Advanced Data Network Solutions ADP Automatic Data Processing ADPCM Adapted Differential Pulse Code Modulation ADPCM Adaptive Differential PCM ADPCM Adaptive Digital PCM ADS-AIT Ameritech Advanced Data Services ADS Abstract Data Structure ADS Associated Directory Services ADSI Analog Display Services Interface ADSL Asymmetrical Digital Subscriber Line ADSP AppleTalk Data Stream Protocol ADSS All Dielectric Self-Supporting ADSU ATM DSU ADTS Automated Digital Terminal Systems AE Application Entity (GSM) AEP AppleTalk Echo Protocol AERM Alignment Error Rate Monitor AERM Alignment Error Rate Monitor (SS7) AF Audio Frequency AFC Automatic Frequency Control AFE Analog Front End AFI Authority and Format Identifier (ISO) AFP AppleTalk Filing Protocol AFPS Automatic Facility Protection Switching AFR Automatic Flexible Routing AFS Andrew File System AFSK Audio Frequency Shift Keying AGC Automatic Gain Control AGCH Access Grant Channel (GSM) AGND Analog Ground AGW Access Gateway AH Authentication Header AHT Average Handle Time AHT Average Hold Time AI Access Interface AI Artificial Intellegence AIM Asynchronous Interface Module AIN Advanced Intelligent Network AIN Advanced Intelligent Network (SS7) AIO Asynchronous Input/Output AIOD Automatic Identification of Outward Dialing AIP ATM Interface Processor (Cisco) AIRS Alarm Identification Reporting System (Harris) AIS-L Alarm Indication Signal-Line AIS-P Alarm Indication Signal-Path AIS-V Alarm Indication Signal-Virtual AIS Alarm Indication Signal (GSM) AIS Automatic Intercept System AIU Analog Interface Unit AIX Advanced Interactive Executive (IBM's Version of UNIX Operating System) ALI Address Location Information ALI Automatic Location Information ALIS Automatic Location Identification System ALIT Automatic Line Insulation Test ALJ Administrative Law Judge ALPS Airline Product Set (Cisco) ALPS Automatic Loop Protection Switching ALTS Alternate Local Transport Services ALU Arithmetic Logic Unit AM Active Monitor AM Administrative Module (AT&T 5ESS) AM Amplitude Modulation AMA Automatic Message Accounting AMACC Automatic Message Accounting Control Center AMADNS AMA Data Networking System AMATPS AMA Teleprocessing System AMD Advanced Micro Devices, Inc. AMI Alternate Mark Inversion AMI Alternative Mark Inversion AMIS Audio Messaging Interchange Specification AMLCD Active Matrix Liquid Crystal Display AMOS Access Mechanized Order System AMP Active Monitor Present (Token Ring) AMP Administrative Module Processor AMP AIN Maintenance Parameter AMPS Advanced Mobile Phone Service/System AMR Adaptive Multi-Rate codec AMRL Adjusted Main Ring Length AN Access Number ANC Access Network Controller ANI Automatic Number Identification ANI Automatic Number Identification (ISDN) ANM Ameritech Network Management ANM Answer Message ANP Automatic Numbering Plan ANR Automatic Network Routing ANS Advanced Network Systems ANSI American National Standards Institute ANVM Active Nonvolatile Memory ANW Advanced Netware AOA Angle Of Arrival AOC Advice Of Charge AoCC Advice of Charge Charging AoCI Advice of Charge Indication AOL America OnLine AON All Optical Network AOS Alternative Operator Services AP Access Point AP Access Provider AP Action Point AP Activation Platform AP Adjunct Processor AP Application Processor/Process/Program APA All Points Addressable APA Auto Port Aggregation APAD Asynchronous Packet Assembler/Disassembler APaRT Automated Packet Recognition/Translation (Cisco) APC Adjacent Point Code APD Avalanche Photo Diode APDU Application Protocol Data Unit API Application Program/Programming Interface APL Analog Private Line APN Access Point Name APNIC Asia Pacific Network Information Center APP Applications Portability Profile APPC Advanced Program-to-Program Communication (IBM) APPC Advanced Program-to-Program Communications APPN+ Next-generation APPN APPN Advanced Peer-to-Peer Networking (IBM) APR Alarm Processing Remote APS Automatic Protection Switching APSB Automatic Protection Switching Byte APT Telephony Applications System APTOS Automated Pricing, Terminals Operations & Services APTT Automatic Progression Trunk Testing APZ Telephony Control System AQL Acceptable Quality Level AR Access Registrar ARA AppleTalk Remote Access ARC ATM Research Consortium ARCnet Attached Resource Computer Network ARCOFI Audio Ringing Codec Filter ARCOS ARCOFI Coefficient Support Program ARD Automatic Ring Down ARE All Routes Explorer (Source Routing) ARFCN Absolute Radio Frequency Channel Number (GSM - UMTS) ARIB Association of Radio Industries and Businesses ARIN American Registry for Internet Numbers ARJ Admissions Reject (RAS) ARL Adjusted Ring Length ARM Asynchronous Response Mode (HDLC) ARP Address Resolution Protocol ARP Address Resolution Protocol (IETF) ARPA Advanced Research Project Agency ARPA Advanced Research Projects Agency ARPANET Advanced Research Projects Agency Network ARPU Average Revenue Per User ARQ Admissions Request (RAS) ARQ Automatic Repeat reQuest ARS Automatic Route Selection ARSB Automated Repair Service Bureau ARU Alarm Relay Unit ARU Automatic Response Unit ARU Audio Response Unit AS56 Accunet Switched 56 AS Autonomous System ASA Authorized Sales Agent ASA Average Speed of Answer ASAI Adjunct Switch Application Interface ASAM ATM Subscriber Access Multiplexer ASB Application Specific Bits ASBR Autonomous System Boundary Router ASC AIN Switch Capabilities ASCII American Standard Code for Information Interexchange ASCII American Standard Code for Information Interexchange (ANSI) ASCU Agent-Set Control Unit ASD Automated Software Distribution ASDS ACCUNET Spectrum of Digital Services (AT&T) ASE Amplified Spontaneous Emissions ASE Application Service Element (GSM) ASF Abstract Specification File ASI Alternate Space Inversion ASI ATM Service Interface ASIC Application Specific Integrated Circuit ASIP AlphaServer Intelligent Peripheral ASK Amplitude Shift Keying ASN.1 Abstract Syntax Notation One (ITU-T) ASN Abstract Syntax Notation (ITU-T) ASN Abstract System Notation ASN Auxiliary Signal Network ASP Active Server Pages ASP Advanced Speech Processor ASP AppleTalk Session Protocol ASP Application Service Provider ASP Assignment Source Point ASP Auxiliary Signal Path ASPI Advanced SCSI Programming Interface ASR Access Service Request ASR Answer-Seizure Ratio ASR Automatic Server Recovery (HP) ASR Automatic Speech Recognition AST Automatic Spanning Tree ASYNCH ASYNCHronous AT&T American Telephone and Telegraph Company AT Access Tandem switch AT Advanced Technology ATA Analogue Telephone Adapter ATAB Area Trunk Assignment Bureau ATB All Trunks Busy ATCP AppleTalk Control Protocol ATDM Asynchronous Time Division Multiplexing ATG Address Translation Gateway (Cisco) ATH Attention Hangup ATI Any Time Interrogation (GSM - UMTS) ATIS Alliance for Telecommunications Industry Solution ATM-LI ATM Link Identifier ATM-PCI ATM Protocol Control Information ATM-SDU ATM Service Data Unit ATM Asynchronous Transfer Mode ATM Automatic Teller Machine ATMM ATM Layer Management ATN Access Tandem Network ATP Acceptance Test Procedure ATP ALPS Tunneling Protocol. ATP AppleTalk Transaction Protocol ATP Application Transaction Programs ATS Advanced Telecommunications Services ATSC American Television Systems Committee ATSC Australian Telecommunication Standardization Committee ATU-C ADSL Transceiver Unit-Central office end ATU-R ADSL Transceiver Unit-Remote terminal end AU Access Unit AUC Authentication Center AUI Attachment Unit Interface AUI Attachment User Interface AUP Acceptable Use Policy AURP AppleTalk Update-based Routing Protocol AUSM ATM User Service Module AUX Apple UNIX AVBO Advanced Voice Busyout AVD Alternate Voice Data AVM ATM Voice Multiplexer AVR Automatic Voltage Regulator AVRU Automated Voice Response Unit AW Admin Workstation AW Administrative Weight AWG American Wire Gauge B-CDMA Broadband Code Division Multiple Access B-CPE Broadband Customer Premises Equipment B-ICI Broadband ISDN Inter-Carrier Interface B-ICI Broadband ISDN InterCarrier Interface B-ISDN Broadband Integrated Services Digital Network B-ISDN Broadband ISDN B3ZS Binary 3 Zero Substitution B6ZS Binary 6 Zero Substitution B8ZS Binary 8 bit Zero Substitution B8ZS Binary 8 Zero Substitution B Bearer channel B Bridge BA Balanced Asynchronous (HDLC) BACP Bandwidth allocation control protocol BAF Bellcore AMA Format BAIC Barring of All Incoming calls BAID Billing Account ID BAIF Billing Account Identification Facility BAN Billing Account Number BANCS Bell Administrative Network Communications System BAOC Barring of All Outgoing calls BAS Basic Activity Subset BAsize Buffer Allocation Size (DQDB, SMDS) BBN Bolt Baranek and Newman BBS Bulletin Board System BBWC Battery-Backed Write Cache Bc Committed Burst Size BCC Base station Color Code (GSM) BCC Base Station Colour Code (GSM - UMTS) BCC Block Calls Cleared (telephony) BCC Block Check Character (BISYNC) BCC Bus Control Card BCCH Broadcast Common Control Channel (GSM) BCCH Broadcast Control Channel (GSM) BCD Binary Coded Decimal BCD Blocked Calls Delayed BCD Blocked Calls Delayed (telephony) BCDIC Binary Coded Decimal Interchange Code BCH Blocked Calls Held BCH Broadcast Channels BCI Backward Call Indicators BCI Bell Canada International BCLB Broadband Connectionless Bearer Service (ATM) BCLID Bulk Calling Line Identification BCM Basic Call Model BCM Bit Compression Multiplexer BCOB Broadband Connection-Oriented Bearer Service (ATM) BCP Best Current Practices (RFC) BCR Blocked Calls Released BCS Basic Combined Subset BCS Business Communication Services BCSM Basic Call State Machine BD Bill Date BDCBB Battery Distribution Circuit Breaker Board BDCS Broadband Digital Cross-Connect System BDFB Battery Distribution Fuse Board BDSA Basic Digital Special Access BDT Telecommunications Development Bureau BE Back-end BE Block Error BECN Backward Explicit Congestion Notification BECN Backward Explicit Congestion Notification (LAPF) BEMS Business Exchange Measured Service BER Basic Encoding Rule(s) BER Bit Error Rate/Ratio BERT Bit Error Rate Test BES Basic Exchange Service BEtag Beginning-End Tag (DQDB, SMDS) BFCV Binary Facility Coding Value BFI Bad Frame Indicator (GSM) BG Billing Group BG Business Group BGID Business Group Identification BGP4 BGP Version 4 BGP Border Gateway Protocol (IETF) BGS Business and Government Services (USW Enterprise) BGW Billing Gateway BHCA Busy Hour Call Attempt(s) BHCC Busy Hour Call Completions BIA Burned-in MAC address BIB Backward Indicator Bit BIB Backward Indicator Bit (SS7) BIBR Backward Indicator Bit Received BIBT Backward Indicator Bit to be Transmitted BIBX Backward Indicator Bit eXpected BICC Bearer Independent Call Control BICI Broadband Inter-Carrier Interface BICRoam Barring of Incoming Calls while Roaming BIGA Bus Interface Gate Array (Cisco) BIND Berkeley Internet Name Domain (DNS) BinHex Binary Hexadecimal BIOS Basic Input/Output System BIP Bit Interleaved Parity (SONET, SDH) BIPI Billing Plug-In BISDN Broadband Integrated Services Digital Network (ISDN) BISUP Broadband ISUP (ISDN User Part) BISYNC BInary SYNChronous (also BSC) BISYNC Binary Synchronous Communications protocol (IBM) BIT BInary Digit BITNET Because It's Time Network BITS Building Integrated Timing Supply BIU Basic Information Unit BL Basic Link BLER BLock Error Rate BLI Busy Lamp Indicator BLSR Bidirectional Line Switched Ring (SONET) BLU Basic Link Unit (SNA) BM Broadband Modem BN Billing Number BNC Bayonet Neil Councilman BNF Backus Naur Form BNI Broadband Network Interface BNM Broadband Network Module BNN Boundary Network Node BNR Bell Northern Research (subsidary of BCE) BNS Bill Number Screening BNS Broadband Network Service BOB Breakout Box BOBI Break-out/Break-in (Cisco) BOC Bell Operating Company BOCP Business Optional Calling Plan BOIC Barring of Outgoing Internaltional Calls BOICexHC Barring of Outgoing International Calls except those to the Home Country BOM Beginning of Message (DQDB, SMDS) BOOTP Bootstrap Protocol BORSCHT Battery feed, Overvoltage protection, Ringing, Signaling, Coding, Hybrid and Testing BP Binding Post BPAD BISYNC Packet Assembler/Disassembler (PSPDN) BPDU Bridge Protocol Data Unit (LAN) BPI Baseline Privacy Interface BPOP Building Point of Presence BPR Business Process Re-engineering BPRZ Bipolar Return to Zero BPS Bits Per Second BPV Bipolar Violation BPX Broadband Packet Exchange (StrataCom) BRA Basic Rate Access BRADS Bellcore Rating Administrative Data System BRCS Business and Residence Centrex Services BRE Bridge Relay Element BRF Bridge Relay Function BRI Basic Rate Interface BRI Basic Rate Interface (ISDN) BRIDS Bellcore Rating Input Database System BRITE Basic Rate Interface Transmission Equipment/Extension BRLU Broadband Remote Line Unit BRS Business Recovery Service BRSU Broadband Remote Switching Unit BS Base Station BS Bearer Service BSA Basic Service Arrangement BSBH Busy Season Busy Hour (telephony) BSC Base Station Controller (GSM) BSC Binary Synchronous Communications protocol (IBM) BSC Bisynchronous Communications BSD Berkeley Software Distribution BSE Basic Service Element BSIC Base Station Identity Code (GSM) BSN Backward Sequence Number (SS7) BSNR Backward Sequence Number Received BSNT Backward Sequence Number to be Transmitted BSP Bell System Practice BSRF Basic System Reference Frequency BSS Base Station Subsystem (GSM) BSS Basic Service Set BSS Basic Synchronized Subset BSS Broadband Switching System BSS Broadcasting Satellite Service BSSGP BSS GPRS Protocol BSSMAP Base Station Subsystem Mobile Application Part (GSM) BSTUN Block Serial Tunnel BT Burst Tolerance (ATM) BTA Basic Trading Area BTA Basic Trading Areas (Rand McNally) BTAM Basic Telecommunications Access Method (SNA) BTN Billing Telephone Number BTS Base Transceiver Station (GSM - UMTS) BTU Basic Transmission Unit Bureau of Standards) BUS Broadcast and Unknown Server BVA Billing Validation Application BVCI BSSGP Virtual Vonnection Identifier BVI Bridge Group Virtual Interface BX.25 AT&T implementation of X.25 BXM Broadband Switch Module C-ISUP Proprietary Cisco protocol based on ISUP C/(N+I) Carrier to Noise plus Interference Ratio C/I Carrier to Interference Ratio C/N Carrier to Noise ratio C/R Command/Response C/R Control/Response Indication Bit C Curb CA Call Appearance (Telecom) CA Certificate/Certification/Certifying Authority CA Collision Avoidance CA Communications Assistant CA Conditional Access (SAT) CABS Carrier Access Billing System CAC Carrier Access Code CAC Connection Admission Control CACD Commission Advisory and Compliance Division CAD Computer Automated/Aided Design CAD Computer Automated/Aided Dispatch CAD Computer Automated/Aided Drafting CADS Computer Automated/Aided Dispatch System CAE Computer Automated/Aided Engineering CAGR Compound Annual Growth Rate CAI Common Air Interface CAL Customer Access Line CAM Cisco Access Manager CAM Computer Automated/Aided Manufacturing CAM Content-Addressable Memory CAMA Centralized Automatic Message Accounting CAMEL Customised Applications for Mobile network Enhanced Logic (3GPP 23.078) CAN Cosmopolitan Area Network CAP CAMEL Application Part CAP Carrierless Amplitude/Phase modulation CAP Competitive Access Provider CAR Cisco Access Registrar CAR Committed access rate CAR Current Activity Report CAS Centralized Attendant Service CAS Channel Associated Signaling CASE Common Application Service Element CASE Computer Aided Software Engineering CAT Carrier Access Tariff CAT Computer Aided Tomography CATIA Computer Assisted Three-dimensional Interactive Application CATV CAble TeleVision CATV Community Antenna TeleVision CAU Cable Access Unit CB Cell Brodcast (GSM) CB Channel Bank CB Citizens Band CBAC Context-Based Access Control CBC Cell Broadcast Center (GSM) CBC Cipher Block Chaining CBCH Cell Brodcast Channel (GSM) CBCU Centralized Broadband Control Unit CBDS Connectionless Broadband Data Service(s) CBEMA Computer and Business Equipment Manufacturers Association CBQ Class-Based Queuing CBR Constant Bit Rate CBR Constant Bit Rate (ATM) CBS Cell Broadcast Services (GSM) CBWFQ Class-Based Weighted Fair Queueing CBX Computerized Branch eXchange CC Call Context CC Call Control CC Cluster Controller (IBM) CC Connect Confirmation CC Country Code (ITU-T) CC Customer Care CCA Call Control Adjunct CCAPI Call Control API CCB Call Control Block CCB Customer Care and Billing CCBS Call Completion on Busy Subscriber CCC Clear Channel Capability CCC Customer Care Center CCCH Common Control Channel (GSM) CCD Charge Coupled Device CCE Consistency Check End CCF Call Control Function CCF Common Citizen Focus CCG Central Clock Generator CCI Common Client Interface CCIE Cisco Certified Internetwork Expert CCIR international radio consultative committee CCIR International Radio Consultative Committee (ITU) CCIS Common Channel Inter-office Signaling (AT&T) CCITT Consultive Committee on International Telephony and Telegraphy (ITU) CCL Common Carrier Line CCLC Carrier Common Line Charge CCNA Cisco Certified Network Associate CCNC Common Channel Signaling Network Control CCO Cisco Connection Online CCOT Cross Office Transfer Time CCR Commitment, Concurrency and Recovery (Application Layer) CCR Consistency Check request CCR Customer Control Reconfiguration CCR Customer Controlled Reconfiguration CCRU Customer Care Retention Unit CCS7 Common Channel SS7 CCS Centi Call Seconds (Hundred seconds calls per hour) CCS Common Channel Signaling CCS Customer Calling Services CCSA Common Control Switching Arrangement CCSN Customer Contact Services Node CCSRC Cisco Subscriber Registration Center CCSS7 Common Channel SS7 (AT&T) CCTV Closed-Circuit TeleVision CCU Common Control Unit CCXML Call Control XML CD-ROM Compact Disc-Read Only Memory CD Call Disconnect (SS7) CD Carrier Detect CD Circuit Details CD Collision Detection (LAN) CD Compact Disc CDAR Customer Dialed Account Recording CDB Call Detail Block CDC Control Data Corporation CDDI Copper Distributed Data Interface CDE Call Detail Element CDF Channel Definition Format CDMA-1X-EV-DO A variant of CDMA 1X which delivers data only CDMA-1X The first generation of CDMA 2000 CDMA Code Division Multiple Access CDO Community Dial Office CDP Cisco Discovery Protocol CDP Customized Dialing Plan CDPD Cellular Digital Packet Data CDPSK Coherent Differential Phase Shift Keying CDR Call Detail Record (OAM) CDR Call Detail Recorder CDR Call Drop Rate CDSL Customer Digital Subscriber Line CDT Central Daylight Time CDU Customer Data Unit CDV Cell Delay Variation (ATM) CDVT Cell Delay Variation Tolerance (ATM) CED Caller Entered Digits CEF Cisco Express Forwarding CEI Comparably Efficient Interconnection CEI Connection Endpoint Identifier (LAPD) CELL1 Cellular One CELP Code Excited Linear Prediction CELP Code Excited Linear Prediction (compression) CENTREX CENTral Exchange CEO Chief Executive Officer CEP Certificate Enrollment Protocol CEP Circular Error Probable CEPT Conference European on Post and Telecommunications CEPT Conference of European Postal and Telecommunications Administrations CER Cell Error Ratio (ATM) CERN European Council for Nuclear Research CERT Computer Emergency Response Team CES Circuit Emulation Service CES Connection Endpoint Suffix CESAR Customer's Enhanced System for Access Requests CET Cisco Encryption Technology CEV Controlled Environment(al) Vault CF Call Forwarding CF Coin First CFA Carrier Failure Alarm CFB Call Forwarding on Busy (SS) CFBNA Call Forwarding for Busy and NoAnswer CFN Call Forward Number CFNRy Call Forwarding on No Reply (SS) CFO Chief Financial Officer CFU/B/NR Call Forwarding Unconditional/Busy/No Reply CFU Call Forwarding Unconditional (SS) CGA Carrier Group Alarm CGB Circuit Group Blocking Message CGF Charging Gateway Function CGI Cell Global Identification (GSM) CGI Cell Global Identity (MCC + MNC + LAC + CID) CGI Common Gateway Interface CGI Common Gateway Interface (Protocol) CGM Computer Graphics Metafile CGSA Cellular Geographic Service/Serving Area CGU Circuit Group Unblocking Message CGW Customer Gateway CH Cell Header CHAP Challenge Handshake Authentication Protocol CHE Cable HeadEnd CHFP Certified Human Factors Professional CHI Conference on Human factors In computing systems CHO Choke Packet CHTML Compact Hyper Text Markup Language CI Carrier Interconnection CI Carrier to Interference ratio CI Cell Identity (GSM) CI Credit Information CI Customer Installation CIA Classical IP over ATM CIB CRC32 Indication Bit (DQDB, SMDS) CIBER Cellular Intercarrier Billing Exchange Roamer Record CIC Carrier/Circuit Identification Code CIC Country Indicator Code CICS Customer Information Control System CID Caller Identification CID Cell ID (GSM - UMTS) CID Channel ID CID Craft Interface Device CIDR Classless Interdomain Routing (IETF) CIDS Calling Identity Delivery & Suppression CIDX Chemical Industry Data Exchange CIF Client Interface Module (SZ) CIF Common Intermediate Format CIIII Computer Inquiry III (DOJ) CIM Computer Integrated Manufacturing CIO Chief Information Officer CIP Channel Interface Processor (Cisco) CIR Committed Information Rate CIR Committed Information Rate (FR) CIRC Cross Interleaved Reed-Solomon Code CISC Complex Instruction Set Computer CIT Collect Information Toll CIT Collect Information Tool CIT Computer Integrated Telephony CIU Communications Interface Unit CIX Commercial Internet eXchange CKL Circuit Location CKSN Ciphering Key Sequence Number (GSM) CKTINT Circuit Interworking software CL&F Common Look and Feel CL Connectionless CL Copper Loop CLASS Custom Local Area Signaling Services CLASS Custom Local Area Signaling Services (Bellcore) classification) CLAW Common Link Access for Workstations CLC Carrier Liaison Committee CLC Common Language Code CLC Competitive Local Carrier CLCI Common Language Code Identifier CLEC Competitive Local Exchange Carrier CLEI Common Language Equipment Identifier CLF Common Language Facility CLFI Common Language Facility Identification CLI Caller ID CLI Command Language Interpreter CLI Command Line Interface (OAM) CLID Calling Line IDentification (ISDN, CLASS) CLIP Calling Line Identification Presentation (SS) CLIR Calling Line Identification Restriction (SS) CLLI Common Language Location Identifier/Identification CLLM Consolidated Link Layer Management (FR) CLNP Connectionless Network Protocol (ISO, ITU-T) CLNS Connectionless Network Service (ISO, ITU-T) CLP Cell Loss Priority CLP Cell Loss Priority (ATM, CLP Bit) CLR Clear CLS Cisco Link Services CLS Connectionless Service CLSI Cisco Link Services Interface CLTP Connectionless Transport Protocol CLTS Connectionless-mode Transport Service CM Cable Modem CM Communications Module (AT&T 5ESS) CM Conference Manager CM Connection Management CM Connection Manager CMC Cellular Mobile Carrier CMDB Centralized Message DataBase CMDR Call Management Detail Records CMDS Centralized Message Distribution System CMI Coded Mark Inversion CMI Control Mode Idle CMIP Common Management Information Protocol (ISO, ITU-T) CMIS Common Management Information Service/System CMISE Common Management Information Service Element (ISO, ITU-T) CMNM Cisco MGC Node Manager CMNS Connection-Mode Network Service CMOL CMIP Over LLC CMOS Complementary Metal-Oxide Semiconductor CMOT CMIP Over TCP/IP CMP Communications Module Processor CMRS Commercial Mobile Radio Services CMS Call Management System {AT&T) CMT Connection Management (FDDI) CMTS Cable Modem Termination System CMU Carnegie Mellon University CN Common Name CNA Customer Number Address CNAB Call Name Delivery Blocking CNCA Carrier Non-Compatible Applications CNE Certified NetWare Engineer CNG CalliNG CNM Customer Network Management CNMA Customer Network Management Agent CNS/AD Cisco Networking Services for Active Directory CNS Complementary Network Service(s) CO-ACD Central Office Automatic Call Distributor CO-LAN Central Office-Local Area Network CO Central Office CO Connection-Oriented COAX COAXial COC Central Office Connection COCOT Customer Operated COin Telephone Code CODEC Coder plus DECoder CODEC COder-DECoder COFA Change of Frame Alignment COI Community Of Interest COLA Cost Of Living Adjustment COLA Customer On Line Authentication COLAN Central Office-based LAN COLP Connected Line Identification Presentation (SS) COLR Connected Line Identification Restriction (SS) COM Continuation of Message (DQDB, SMDS) COMC Communications Controller (SNA) COMPANDER COMpressor/exPANDER CONF CONFerence CONP Connection-Oriented Network Protocol CONS Connection-Oriented Network Service (ISO, ITU-T) COP Customer Ordering Platform COPI Collector Plug-In COPS Common Open Policy Service COPT Customer Owned Public Telephone CORBA Common Object Request Broker Architecture COS Class Of Service COS Corporation for Open Systems COSE Common Open Software Environment COSMOS Central Office System for Mainframe Operations COT Central Office Terminal COT Continuity Test Message COTS Commercial Off-the-Shelf (stuff) CP Cell Payload CP Connection Point CP Control Point CP Control/Coordination Processor CP Customer Premises CPC Call Processing Control CPC Calling Party Category CPCN Certificate of Public Convenience and Necessity CPCS Call Processing Control System CPCS Common Part Convergence Sublayer CPE Certified Professional CPE Customer Premise(s) Equipment CPG Call Progress Message CPI/C Common Programming Interface for Communication CPI Computer-PBX Interface CPI Consumer Price Index CPM Cost Proxy Model CPNI Customer Proprietary Number/Network Information CPNIE Called Party Number Information Element CPP Calling Party Pays CPP Combinet Proprietary Protocol (Cisco) CPR Core Process Re-engineering CPS Customer Premises System CPS Cycles Per Second CPU Central Processor/Processing Unit CPUC California Public Utilities Commission CQ Custom Queuing CQM Circuit Group Querry (SS7) CQR CQM Response (SS7) CR Call Reference CR Certificate Request CR Conditional Requirement CR Connect Request (SS7) CRA Circuit Reservation Acknowledgment Message CRC Cyclic Redundancy Check(word) CRC Cyclical Redundancy Checking CRED Credit Card Calling CREF Connection Refused CRF Concentrator Relay Function (ATM) CRIS Customer Records Information System CRL Certificate Revocation List CRM Circuit Reservation Message CRM Customer Relationship Management crossconnect frame CRP Customer Routing Point CRS Cell relay Service CRS Configuration Report Server CRT Cathode Ray Tube CRTC Canadian Radio-television and Telecommunications CRU Customer Retention Unit CRV Call Reference Value (Q.931) CS-1 Capability Set 1 CS-ACELP Conjugate Structure Algebraic Code Excited Linear Prediction (compression) CS-PDU Convergence Sub-layer PDU CS1 Capabilities Set 1 CS2 Capabilities Set 2 CS Call Segment CS Capability Set CS Carrier Services CS Configuration Server Module(SZ) CS Convergence Sublayer (ATM) CSA Call path Services Architecture CSA Canadian Standards Association CSA Carrier Serving/Service Area(s) CSA Custom Service Arrangement CSAP Core Service Access Point CSB Customer Service Bureau CSC Circuit Supervision Control CSC Common Signaling Channel CSC Customer Service Center CSDC Circuit Switched Digital Capability CSDN Circuit Switched Data Network CSDS Circuit Switched Digital Service CSDU Core Service Data Unit CSE CAMEL Service Environment CSFS Customer Support Forwarding Service CSH Convergence Sublayer Header CSI Called Subscriber Identification CSIMA Client Side Image Map Authoring CSLIP Compressed Serial Link Internet Protocol CSM Call Switching Module CSM Cisco Service Management system of Operations, Administration, Maintenance, and Provisioning (OAM&P) CSMA/CA CSMA with Collision Avoidance (LAN) CSMA/CD Carrier Sense Multiple Access with Collision Detection CSMA/CD CSMA with Collision Detection (LAN) CSMA Carrier Sense Multiple Access CSMA Carrier Sense Multiple Access (LAN) CSN Central/Customer Service Node CSNET Computer Science Network CSNP Complete Sequence Number PDU CSO Composite Second Order CSP Chip Scale Package CSPDN Circuit Switched Public Data Network CSR Consistency Check Request CSR Customer Service Record CSR Customer Service Representative (OAM) CSS Customer Support System CST Central Standard Time CST Convergence Sublayer Trailer CST Cooperative Scheduled Testing CSTA Computer Supported Telecommunications Application CSU Channel Service Unit CSV Comma Separated Values CT0 Zero generation cordless telephony (analogue technology and severe limitations in terms of range and security) CT1 First generation cordless telephony (greater range and security) CT2-CAI Second generation cordless telephony-common air interface CT2 Second generation cordless telephony (digital with greater range, improved security and a wide range of new functionalities) CT Call Transfer CT Call Type CT Channel Termination CT Common Transport CT Computer Telephony CT Computerized Tomography CT Cordless Telephone/Telephony CTA Cordless Terminal Adaptor (DECT) CTB Composite Triple Beat CTD Cell Transfer Delay (ATM) CTI Computer Telephony Integration CTIA Cellular Telecommunications Industry Association CTM Cordless Terminal Mobility CTR Common Technical Regulation, part of the ETSI standardization process CTS Clear To Send CTS Clear To Send (EIA-232-E) CTS Common Transport Semantic (IBM) CTU Channel Test Unit CTX CenTreX system number CU Channel Unit CU Coding Unit CU Control Unit CUG Closed User Group (GSM) Custom Service Arrangement CV Coding Violation CVM Cluster Veritas Volume Manager CVN Customer Virtual Network CVR Circuit Validation Response Message CVSD Continuously Variable Slope Delta Modulation CVSDM Continual Variable Slope Delta Modulation CVT Circuit Validation Test Message CW Call Waiting (SS) CWAF Cisco Web Application Framework CWC Center Weight Control CWID Call Waiting IDentification service CWIDO Call Waiting IDentification with Options service CxBus Cisco Extended Bus D-AMPS Digital AMPS (US wireless standard, IS-136) D-H Diffie-Hellman (algorithm) D-WDM Dense-Wavelength Division Multiplexing D/I Drop and Insert D3 Third generation channel bank (24 chans on T1) D4 Fourth generation channel bank (48 voice chans on 2 T1's or 1 T-1C) D Data Channel DA Destination Address (LAN) DA Device Address (SNA) DA Digital Access DA Directory Assistance DA Distribution Area DAC Digital to Analogue Convertor DAC Dual Attachment Concentrator (FDDI) DACK DMA ACK DACS Digital Access and Cross-connect System (AT&T) DACS Digital Access and Crossconnect System DAEDR Delimitation, Alignment and Error Detection procedure in Receive Direction DAL Dedicated/Direct Access Line DAMA Demand Assigned Multiple Access DAML Digital Added Main Line DAN DECT Access Node DAO Directory Assistance Only DAP Data Access Protocol (DEC's DNA - Application Layer) DAP Directory Access Protocol DAP Directory Access Protocol (AppleTalk) DAP Document Application Profile DARPA Defense Advanced Research Project Agency DARPA Defense Advanced Research Projects Agency DAS Dual Attachment Station DAS Dual Attachment Station (FDDI) DAS Dynamically Assigned Socket DASD Direct Access Storage Device DAT Digital Audio Tape DAU Data Adapter Unit DAVIC Digital Audio Video Council DB2 DATABASE2 (IBM) DB Database dB decibel DB Dummy Burst DBAC DataBase Administration Center DBAS DataBase Administration System DBCS Data Bank Control System DBCS Double-Byte Character Sets DBIF Database Interface Module (SZ) DBMS Database Management System DBN Dial-Back Number DBOS Data Bank Organization System DBS Direct Broadcast Satellite DBS Direct Broadcats Satellite DBSS Data Bank Security System DBW Decibel per Watt DC Direct Current DCA Digital Communications Associates DCA Document Content Architecture DCA Dynamic Channel Assignment DCB Digital Channel Bank DCC Data Communications Channel (SONET) DCC Data Country Code DCC Digital Control Channel DCCH Dedicated Control Channel (GSM, SDCCH, SACCH and FACCH) DCCX Direct Circuit Control Exchange DCE Data Circuit-terminating Equipment DCE Data Communications Equipment DCE Distributed Computing Environment DCER Data Circuit-terminating Equipment Ready DCF Dispersion Compensating Fiber DCF Distributed Coordination Function DCH Data Clearing House DCM Digital Circuit Multiplication (same as DSI) DCN Data Communications Network DCO Digital Central Office DCOM Distributed Component Object Model DCP Designated Carrier Plan DCP Digital Communications Protocol DCPSK Differentially Coherent Phase Shift Keying DCR Dynamically Controlled Routing DCS-1800 Digital Cordless Standard DCS Digital Communications System DCS Digital Crossconnect System DCT Discrete Cosine Transform DD Database Description DD Domain Directory DDCMP Digital Data Communications Message Protocol (DNA) DDD Direct Distance Dialing DDI Direct dial-in DDL Data Definition Language (SQL) DDLMP Digital Equipment Corporation data link control DDM Digital Data Multiplexer DDM Distributed Data Management DDN Defense Data Network DDP Datagram Delivery Protocol (AppleTalk) DDR Dial-on-Demand Routing DDR Double Data Rate DDR Double Data Rate (SDRAM) DDS Dataphone Digital Service DDS Dataphone Digital Service (AT&T) DDS Digital Data Service DDSD Delay Dial Start Dial DDSN Distributed Diagnostics and Service Network DE Discard Eligibility DE Discard Eligibility (LAPF) DEA Data Encryption Algorithm DEA Digital Exchange Access DEC Digital Equipment Corporation DECmcc DEC Management Control Center DECT Digital European Cordless Telephone DECT Digitally Enhanced Cordless Telecommunications DEK Data Encryption Key DEPSK Differential Encoded Phase Shift Keying DER Distinguished Encoding Rules DES Data Encryption Standard DES Data Encryption Standard (NIST) DES Destination End Station DES Digital Encryption Standard DF Distributing Frame DF Don't Fragment (IP) DFC Data Flow Control DFL Distributed Feedback Laser DFRI Datacom Reference Frame Input DFS Distributed File System DFSK Double Frequency Shift Keying DHCP Dynamic Host Configuration Protocol DIA Document Interchange Architecture DID Direct Inward Dialing DID Direct(ed) Inward Dialing DIDR Direct Inward Dial Number Range DILIC Dual In-Line Integrated Circuit DIMM Dual In-line Memory Module DIMM Dual Inline Memory Module DIP Dual In-line Package DISA Direct inward station access DISA Direct Inward System Access DISC Disconnect DIT Directory Information Tree DL Data Link DLC Digital Loop Carrier DLCI Data Link Connection Identifier/Indicator (GSM, LAPD, LAPF) DLCI Data Link Connection Indicator DLE Data Link Escape (BISYNC) DLH Data Link Layer Header DLL Dial Long Line DLL Dynamic Link Library DLM Distributed Lock Manager DLR Design Layout Record DLR Destination Local Reference DLS Data Link Switching DLSw+ Data-Link Switching plus (Cisco) DLT Data Link Layer Trailer DLU Dependent LU DLU Digital LU DLUR Dependent LU Requester DLUS Dependent LU Server DM Delta Modulation DM Dialogue Management DM Disconnected Mode (HDLC) DMA Direct Memory Access DMAC destination MAC DMAC Direct Memory Access Control DMB Dynamic Multipoint Bridging DME Distributed Management Environment DMI Desktop Management Interface DMI Digital Multiplex(ed) Interface DML Data Manipulation Language (SQL) DMP Data Movement Processor (Cisco) DMP Device Management Protocol DMPB Digital Multipoint Bridging DMS Digital Modular Switch DMS Digital Multiplex Switch DMS Digital Multiplex System DMT Discrete Multitone Technology DMTS Distinguished Member of Technical Staff DN Dialed Number DN Directory Number DN Directory Number (SS7) DN Distinguished Name (X.500) DNA Data Network Address DNA Digital Network Architecture DNA DoNotAge (bit) DNCF Directory Number Call Forwarding DNHR Dynamic Nonhierarchical Routing DNI Data Network Interface DNIA Dialed Number Identification Service DNIC Data Network Identification Code DNIC Data Network Identification Code (X.121) DNIC Data Network Interface (2B+D ISDN) DNIS Dialed Number Identification Service DNS Domain Name System DNS Domain Name System (IETF) DNSP Distributed Networked Services Platform DNU Digital Networking Unit DOC Dynamic Overload Control DOCSIS Data Over Cable Service Interface Specification DOD Department Of Defence DOD Direct Outward Dialing DOI Domain Of Interpretation DOMSTATS Domestic Satellite Carriers DOS Disk Operating System DOS Domestic Operator Service DOV Data Over Voice DOW Day Of Week DP Data Processing DP Detection Point DP Dial Pulse DPA Distributed Power Architecture DPBX Digital Private Brance Exchange DPBX Digital Private Branch eXchange DPC Destination Point Code (SS7) DPCM Differential Pulse Code Modulation DPDU Data (link) Protocol Data Unit DPE Digital Parity Error DPG Digital Pair Gain DPL Digital Power Line DPM call Defect Per Million DPNSS Digital Private Network Signaling System (BT) DPO Dial Pulse Originate DPSK Differential Phase Shift Keying DPSK Digital Phase Shift Keying DPT Dial Pulse Terminate DPT Dynamic Packet Transport DQDB Distributed Queue Dual Bus DQDB Distributed Queue Dual Bus (IEEE 802.6) DQPSK Digital Quadrature Phase Shift Keying DR Digit Receiver DRA Division of Ratepayer Advocates DRAD Digital Remote Antenna Driver DRAM Dynamic Random Access Memory DRAM Dynamic Random Access Memory (RAM) DRCS Dynamically Redefinable Charectes Sets DRDA Distributed Relational Database Architecture (IBM) DRP Director Response Protocol (Cisco) DRP Dispute Resolution Procedure DRX Discontinous Reception (GSM) DS-0 Digital Signal level 0 DS-1 Digital Signal level 1 DS-2 Digital Signal level 2 DS-3 Digital Signal level 3 DS-CDMA Direct Sequence CDMA DS0 Digital Signal Zero - 64 Kb/s data/voice chan DS1 Digital Signal One (DS0 x 24 = 24 DS0) DS2 Digital Signal 2 (DS1 x 4 = 96 DS0) DS3 Digital Signal 3(DS2 x 7 = 672 DS0) DS Data Services DS Digital Signal DS Directory Services DS Directory Synchronization DSA Digital Signature Algorithm DSA Directory System Agent DSAP Destination Service Access Point (LLC) DSC Digital Switch Corporation DSE Data Switching Equipment DSE Data Switching Exchange DSF Dispersion-Shifted Fiber DSG Data Systems Group DSI Digital Speech Interpolation DSL Digital Subscriber Line DSLAM Digital Subscriber Line Access Multiplexer DSMA/CD Digital Sense Multiple Access with Collision Detection DSMA Digital Sense Multiple Access DSN Data Source Name (ODBC) DSN Delivery Status Notification DSN Digital Switched Network DSODP Digital Service Office Dataport DSP Digital Signal Processor/Processing DSP Directory Service Protocol DSP Display System Protocol (packet switching) DSP Domain Specific Part DSPU Downstream Physical Unit DSR Data Set Ready DSRR Digital Short Range Radio DSS Decision Support System DSS Digital Subscriber Signaling system (ISDN, B-ISDN) DSS Digital Switched Services DSSS Direct Sequence Spread Spectrum DSU Data/Digital Service Unit DSX Digital Signal Cross-connect DSX termination hardware for DS1 and DS3's DT Dedicated Transport DTAU Digital Test Access Unit DTD Document Type Declaration DTE Data Terminal Equipment DTF Dial Tone First DTF Digital Transmission Facility DTH Direct to Home DTI Digital Trunk Interface DTL Designated Transit List DTLU Digital Terminal Line Unit DTMF Dual Tone Multi Frequency DTMF Dual Tone Multi(ple) Frequency DTP DDSN Transfer Protocol DTP Distributed Transation Processing DTR Data Terminal ready DTR Data Terminal Ready (EIA-232-E) DTS Data Terminal Set DTS Digital Terminal Systems DTS Digital Transmission Systems DTU Data Terminal Unit DTV Digital Television DTZ Discontinuous Transmission DUA Directory User Agent DUAL Diffusing Update Algorithm (Cisco) DUP Data User Part DVB Digital Video Broadcasting DVI Digital Video Interleaved DVM Data Voice Multiplexer DVM Digital Volt Meter DVMRP Distance Vector Multicast Routing Protocol DVT Digital Video Terminal DVVI Data, Voice, Video integration DWDM Dense Wavelength Division Multiplexing DX Duplex DXC Digital Cross Connect DXI Data eXchange Interface DXI Data Exchange Interface (ATM, SMDS) E&M Ear and Mouth EA Address field Extension (HDLC) EA Equal Access EA Extended Address EAD Expedited Application Docket EADAS Engineering and Administration Data Acquisition System EADASNM EADAS Network Administration EAEO Equal Access End Office EAI Enterprise Application Integration EAMF Equal Access Multifrequency EAOSS Exchange Access Operator Service Signaling EAP Extensible Authentication Protocol EARN European Academic Research Network EARS Easy Access Request System EAS Equal Access Signaling EAS Extended Area Service EBAT Electronic Bill Analysis Tool EBCDIC Extended Binary Coded Decimal Information/Interchange Code EBS Electronic Business Sets EBU European Broadcasting Union EC Echo Canceling EC Electrical Carrier EC European Community ECC Error Checking/Correction Code ECDSA Elliptic Curve Digital Signature Algorithm ECM Error Correction Mode ECMA European Computer Manufacturer Association ECN Electronic Communication Network ECN Explicit Congestion Notification (FR) ECSA Exchange Carriers Standards Association ECTF Enterprise Computer Telephony Forum ED Ending Delimiter (LAN) EDFA Erbium-Doped Fiber Amplifier EDGE Enhanced Data rate for GSM Evolution EDGE Enhanced Data rate(s) for GSM Evolution EDI Electronic Data Interchange (ANSI) EDI Electronic Data Interexchange EDIFACT EDI for Administration, Commerce, and Transportation EDIFACT Electronic Data Interchange For Administration, Commerce, and Trade (ANSI) EDO Extended Data Out EDP Electronic Data Processing EDP Event Detection Point EDSX Electronic Digital Signal Cross-Connect EECM End-to-End Call Manager EEO Equal Employment Opportunities EEO Extremely Elliptical Orbit EEPROM Electrically Erasable Programmable Read-Only Memory EF Entrace Facility EFCI Explicit Forward Congestion Indicator (ATM) EFD Event Forwarding Discriminator EFM Eight-Fourteen Modulation EFR Enhanced Full Rate EFS End-of-Frame Sequence (LAN) EFS Error Free Second(s) EFS Error Free Seconds EFT Electronic Funds Transfer EGA Enhanced Graphics Adaptor EGP Exterior Gateway Protocol EGP Exterior Gateway Protocol (IETF) EGSM Extended (frequency range) GSM EHF Extremely High Frequency EHP Electron-Hole Pairs EHSA Enhanced High System Availability EI Expansion Interface EIA Electronics Industry Association EIDE Enhanced Integrated Device Electronics EIGRP Enhanced Interior Gateway Routing Protocol (Cisco) EIM Errored Interval Monitored EIP Ethernet Interface Processor (Cisco) EIR Equipment Identity Register EIR Equipment Identity Register (GSM) EIR Equipment Identity/Identification Register EIR Excess Information Rate (FR) EIRP Effective Isotropic Radiated Power EIRP Effective Isotropic Radiated Power (Radio) EISA Extended Industry Standard Architecture EKTS Electronic Key Telephone Service ELAN emulated LAN (ATM) ELAP EtherTalk Link Acces Protocol (AppleTalk) ELEC Ethernet Local Exchange Carrier Electronic Switched Network ELF Extremely Low Frequency ELFEXT Equal Level Far End Crosstalk ELMI Enhanced Local Management Interface EM Element Manager EMA Electronic Mail Association EMA Enterprise Management Architecture EMBARC Electronic Mail Broadcast to a Roaming Computer EMF Electro-Magnetic Force EMG Extension Module Group EMI Electro-Magnetic Interference EML Element Management Layer EMR Exchange Message Record EMS Element Management System (Network Mgmt.) EMS Emergency Management Services EMS Event Management Service EMS Expanded Memory Specification EN Egress Node EN End Node ENFIA Exchange Network Facilities for Interstate Access ENIAC Electronic Numerical Integrator and Calculator ENQ Enquiry ENS Enterprise Network Services EO End Office EOB End of Bus (DQDB) EOC Embedded Operations Channel (SONET) EOD End of Dialing EOF End Of File EOL End Of Line EOM End of Message (DQDB, SMDS) EOT End of Transmission (BISYNC) EPD Early Packet Discard (ATM) EPG Electronic Programme Guide EPROM Erasable Programmable Read Only Memory EPS Enhanced Paging Service EPSCS Enhanced Private Switch Controlled System EPSCS Enhanced Private Switched Communications Service Equipment ER Egress Router ER Equipment Room ER Explicit Rate (ATM) ERC Easily Recognizable Code ERD Enhanced Repeat Dial service Ergonomist ERL Echo Return Loss ERM Explicit Rate Marketing ERMES Enhanced Radio Messaging System ERO European Radiocommunications Office ERP Effective Radiated Power ES-IS End System-to-Intermediate System ES Earth Station ES Echo Suppressor ES End-System (ISO) ES Errored Second ESCON Enterprise System Connection (IBM) ESD Electro-Static Discharge ESDI Enhanced Small Device Interface ESDRAM Enhanced SDRAM ESF Extended Super Frame ESFDL Extended Super Frame Data-Link ESG Enhanced Service Gateway ESI End System Identifier ESIG European SMDS Interest Group ESME External Short Message Entity ESMR Enhanced Special Mobile Radio ESMR Enhanced Specialized Mobile Radio ESMTP Extended Simple Mail Transfer Protocol ESN Electronic Serial Number ESN Emergency Service Number ESN Equipment Serial Number ESP Encapsulating Security Payload ESP End Signaling Point ESP Enhanced Service Provider(s) ESP Enhanced Service Providers ESP Extended Services Processor (Cisco) ESPRIT European Strategic Programme for Research and Development in Information Technology ESS Electronic Switching System ET Exchange Termination ETACS Extended TACS ETB End of Text Block (BISYNC) ETC Eligible Telecommunications ETC Enhanced Throughput Cellular ETC Exchange Terminal Circuit ETE End-To-End ETF Electronic Telephone Features ETN Electronic Tandem Network ETR Early Token Release (Token Ring, FDDI) ETS European Telecommunications Standard ETSI European Telecommunications Standards Institute ETX End of Text (BISYNC) EUCL End User Common Line EULA End User License Agreement EUM End User Migration EUN External Update Notification EUnet European UNIX Network EWOS European Workshop for Open Systems Exchange Carrier EXCO EXchange Central Office EXM Exit Message EXZ Excessive Zeros FA Favourite Area FABS Flexible Automated Billing System FACCH Fast ACCH (GSM) FACS Facility Assignment and Control System FAQ Frequently Asked Question FAS Frame Alignment Sequence (T-1) FAS Frame Alignment Signal FAT File Allocation Table FAT File Allocation Table (Operating Systems) FAW Frame Alignment Word FAX facsimile FB Framing Bit FB Frequency Correction Burst FBWA Fixed Broadband Wireless Access FCAPS Fault, Configuration, Accounting, Performance and Security (OAM) FCC Federal Communications Commission FCC Forward Control Channel FCCH Frequency Correction Channel (GSM) FCDR Fast CDR Handler FCFS First Come First Served FCIF Full Common Intermediate Format FCRAM Fast Cycle RAM FCS Frame Check Sequence FCS Frame Check Sequence (Data Link Protocols) FDA Food and Drug Administration FDD Frequency Division Duplex FDDI Fiber Distributed Data Interface FDDI Fiber Distributed Data Interface (ANSI) FDF Fiber Distribution Frame FDI Feeder Distribution Interface FDL Facility Data Link FDLC Fujitsu Digital Loop Carrier FDM Frequency Division Multiplexer FDM Frequency Division Multiplexer/Multiplexing FDMA Frequency Division Multiple Access FDX Full-Duplex FE Fast Ethernet FE Frame synchronization bit error Event FE Front-end FEA Federal Executive Agencies FEAC Far End Alarm and Control FEAL Fast Encryption ALgorithm FEBE-f Far End Block Error Count-fast data FEBE-i Far End Block Error Count-interleaved data FEBE Far End Block Error FEC Forward Error Correction FECC-f Forward Error Correction Count-fast data FECC-i Forward Error Correction Count-interleaved data FECC Far-End Camera Control FECN Forward Explicit Congestion Notification FECN Forward Explicit Congestion Notification (LAPF) FEH Fatal Exception Handler FEIP Fast Ethernet Interface Processor (Cisco) FELB Far End Loop Back FEP Front End Processor FEP Front End Processor (IBM) FEPS Facility and Equipment Planning System FERF Far End Receive Failure FET Field Effect Transistor FEX Foreign EXchange FEXT Far-End Cross Talk FFOL FDDI Follow-On LANs FFS For Further Study FG Feature Group FG Frame Ground FGD Feature Group D FGD Feature Group D (protocol to transmit MIN and PIC for cellular) FH-CDMA Frequency Hopping CDMA FH Fiber Hub FH Frame Handler FH Frequency Hopping FHSS Frequency Hopping Spread Spectrum FI Facility Identification FIB Forward Indicator Bit (SS7) FIBR Forward Indicator Bit Received FIBT Forward Indicator Bit to be Transmitted FIBX Forward Indicator Bit eXpected FIC Frame Identification Code FICON Fiber Connectivity FID Feature Identification code FID Field IDentifier FID Format Identification (SNA) FIFO First In First Out FIFO First In, First Out FIP FDDI Interface Processor (Cisco) FIPS Federal Information Processing Standards FIRP Federal Internetworking Requirements Panel FISU Fill-In Signal Unit (SS7) FITL Fiber In The Loop FLL Fixed Loss Loop FLM Fiber Loop Multiplexer FLTL Full Line Terminal FM Frequency Modulation FM Function Management FMC Fixed Mobile Convergence FN Fiber Node FN Frame Number (GSM) FNPRM Further Notice of Proposed Rulemaking FNS Feature Node Services FO Fiber Optics FOC Firm Order Confirmation FOD Fax On Demand FoIP Fax Over Internet Protocol FOIRL Fiber Optic Inter-Repeater Link FOT Fiber Optic Terminal FOTS Fiber Optic Transmission System FOTS Fiber Optics Transmission System FPLMTS Future Public Land Mobile Telecommunications System FPM Fast Page Mode FPP Flexible Pricing Plan FPS Fast Packet Switching FPS Framing Pattern Sequence FPU Floating Point Unit FQDN Fully Qualified Domain Name FQPCID Fully Qualified Procedure Correlation Identifier FR-PVC Frame Relay Permanent Virtual Connection FR-SSCS Frame Relay Service Specific Convergence Sub-layer FR Frame Relay FRA Fixed Radio Access FRA Fixed Radio Access (WLL) FRAC Frame Aligner Circuit FRAD Frame Relay Access Device FRAD Frame Relay Access Device (Cisco) FRAD Frame Relay Assembler/Disassembler FRAS Frame Relay Access Support (Cisco) FRASM Frame Relay Access Service Module FRD Feature Request Document FRF-LMI Frame Relay Forum-Local Management Interface FRF Frame Relay Forum FRL Facility Restriction Level FRMR Frame Reject (HDLC) FRP Fragmentation Protocol (VINES) FRS Frame Relay Service FRS Frame Relay Switch FRSS Frame Relay Switching System FRTS Frame Relay Traffic Shaping FS Feature Server FS Frame Status FSA Fiber Serving Area FSD Feature Specific Document FSDPSK Filtered Symmetric Differential Phase Shift Keying FSIP Fast Serial Interface Processor (Cisco) FSK Frequency Shift Keying FSL Flexible Service Logic FSM Finite State Machine FSMO Flexible Single-Master Operation FSN Forward Sequence Number (SS7) FSOQ Frequency Shift Offset Quadrature Modulation FSS Facility Selective Service FSS Fixed Satellite Service FSSRP Fast Simple Server Redundancy Protocol FST Fast Sequenced Transport (Cisco) FT1 Fractional T1 FTA Federal Telecommunications Act of 1996 FTAM File Transfer Access & Management FTAM File Transfer, Access and Management (ISO) FTC Fault Tolerance Controller FTE Full Time Equivalent FTP File Transfer Protocol FTP File Transfer Protocol (IETF) FTSC Federal Telecommunications Standards Committee FTTC Fiber To The Curb FTTH Fiber To The Home FTTL Fiber To The Loop FTTN Fiber To The Neighborhood FUNI Frame User-Network Interface (ATM) FUT Friendly User Trial FX Foreign Exchange FXO Foreign Exchange Office FXS Foreign Exchange Station FXS Foreign Exchange Subscriber/Station G/T Gain to Thermal noise G Giga G Giga- GAAP Generally Accepted Accounting Principles GAP Generic Access Parameter GAP Generic Access Profile (DECT) GBPS / GB/s GigaBits Per Second GBPS GigaBits Per Second GC Group Card GCAC Generic Connection Admission Control (ATM) GCD Graphic Codepoint Definition GCF Global Certification Forum GCI General Circuit Interface GCR General Configuration Register GCRA Generic Cell Rate Algorithm (ATM) GDI Generic Data interface GDOP Geometric Dilution of Precision GDP Gateway Discovery Protocol (Cisco) GE General Electric GEO Geostationary Earth Orbit GEOS Geostationary Earth Orbit Satellite(s) GERAN GSM-EDGE Radio Access Network GFC Generic Flow Control GFC Generic Flow Control (ATM) GFI General Format Identifier (X.25) GFLOPS One Billion Floating Point Operations per Second GGP Gateway to Gateway Protocol GGRF GSM Global Roaming Forum GGSN Gateway GPRS Support Node(s) GGSN Gateway GPRS Support Nodes GHZ GigaHertz GIF Graphic Interface Format GIN GSM Information Network GIO Generic Interface for Operations (SMDS) GIS Geographic Information Systems GIX Global Internet eXchange GK GateKeeper GKTMP Gatekeeper Transaction Message Protocol (Cisco) GMPCS Global Mobile Personal Communications by Satellite GMS Geostationary Meteorological Satellite GMSC Gateway Mobile Switching Center (GSM) GMSK Gaussian filtered Minimum Shift Keying GMT Greenwich Mean Team GN Generic Name GN Geographic Number (GSM - UMTS) GNS Get Nearest Server GO General Order GOB Group of Blocks GOS Grade Of Service GOSIP Government Open System(s) Interconnection Profile GP Group Processor GPPC General Purpose Power Controller GPRS General Packet Radio Service (GSM - UMTS) GPRS General(ized) Packet Radio Service/System GPRS Generalized Packet Radio Service/System GPS Global Position Satellite/System GPS Global Positioning Service/System GPS Global Positioning System GRE Generic Routing Encapsulation (Cisco) GRIN Graded-Index Fiber GRJ Geatekeeper Reject (RAS) GRQ Gatekeeper Request (RAS) GRS Group Reset Message GRX GPRS Roaming Exchange GS Gate Server GS Ground Start GS Group Separator GSA General Services Administration GSC Gateway Switching Center GSM-R GSM-Railway GSM Global Standard/System for Mobile telecommunications GSN GPRS support node GSP Global Service Provider GSS Generic Service State GSS Group Switching Subsystem GTP GPRS Tunneling Protocol GTT Global Title Translation(s) GTT Global Title Translations GTV Global Title Value GTXC Global Telephone Exchange Carrier GUI Graphical/Graphics User Interface GUI Graphics User Interface GW Gateway H Header HA High Availability HAC Hands-Free Add-On Circuit HCDS High Capacity Data Services HCDS High Capacity Digital Services HCM High Capacity Multiplexing HCS Header Check Sequence HCS Hierarchical Cell Structure HCSPR Hundred Call Seconds Per Hour HCV High Capacity Voice HDB3 High-Density Bipolar Three-Bit substitution HDLC High (level) Data Link Control HDLC High level Data Link Control HDML Handheld Device Markup Language HDOP Horizontal Dilution of Precision HDR frame HeaDeR HDS Historical Data Server HDSL High bit rate Digital Subscriber Line HDT Host Digital Terminal HDTM Half-Duplex Transmission Module (X.25) HDTV High Definition Television HDX Half-Duplex HE Head End HE Header Extension (DQDB, SMDS) HE Human Ergonomics HEC Header Error Control HEC Header Error Control (ATM) HEL Header Extension Length (DQDB, SMDS) HEX PPB Handler for External Systems HF/E Human Factors / Ergonomics HF High Frequency HF Human Factors HFC Hybrid Fiber Coax HFC Hybrid Fiber Coaxial cable HFE Hardware Forwarding Engine HFES Human Factors and Ergonomics Society HFR Hardware Failure Rate HFS Hierarchical File Storage HHDLC High-level Data Link Control (ISO) HIBCC Health Industry Business Communications Council HICAP High Capacity Digital Services HID Human Interface Device HILI Higher Layers and Internetworking (IEEE 802) HIP HSSI Interface Processor (Cisco) HIPERLAN High Performance Radio Local Access Network HIPPI High Performance Parallel Interface HIPPI HIgh performance Parallel Processing Interface HLD High Level Design HLFD High Level Functional Design HLL High Level Language HLM Heterogeneous LAN Manager HLPI Higher Layer Protocol Identifier (DQDB, SMDS) HLR Home Location Register HLR Home Location Register (GSM - UMTS) HMA High Memory Area HMAC Hash-based Message Authentication Code HMI Human-Machine Interface HMLP High-speed Multi Layer Protocol HMW High Molecular Weight HNPA Home Numbering Plan Area HO Handover HO High Order HOB Head of Bus (DQDB) HOSTID Host Identifier HP/UX HP's Version of UNIX Operating System HP Hewlett-Packard HPA High Power Amplifier HPAD Host Packet Assembler/Disassembler (BPAD) HPC High Performance Computing HPC High Probability of Completion HPCC High Performance Computing and Communications HPCS High Performance Computing Systems HPFS High Performance File System HPQLOMGC HP Lights-Out Migration Command Line HPQLOMIG HP Lights-Out Migration HPR High Performance Routing HQ Headquarters HS High Speed HSC Hierarchical Storage Controller HSCI High Speed Communications Interface (Cisco) HSCSD High Speed Circuit Switched Data HSLAN High Speed LAN HSM Hardware Security Module (SZ) HSN Hopping Sequence Number HSPSD High Speed Packet Switched Data HSRP Hot Standby Router Protocol (Cisco) HSSI High Speed Serial Interface (ANSI) HT Holding Time HTML HyperText Markup Language HTTP HyperText Transfer Protocol (IETF) HTTP Hypertext Transfer Protocol (Protocol) HTTP HyperText Transmission Protocol HTTPS HTTP Secure HTU-C HDSL Transmission Unit-Central Office HTU-R HDSL Transmission Unit-Remote HTU HDSL Transmission Unit Hz Hertz I&R Installation and Repair I/O Input and Output IA5 International Alphabet #5 (ITU-T) IAA Initial Address Acknowledgement IAB Internet Advisory Board IAB Internet Architecture Board (formerly Activities) IAC Initial Alignment Control IAC International Access Code IAC Internet Access Controler IACS Integrated Access and Crossconnect System IAD Integrated Access Device IAM Initial Address Message IAM Initial Address Message (SS7) IANA Internet Address Naming Authority IAR Initial Address Reject IAT Integrated Access Terminal IBC In-Band Control IBDN Integrated Building Distrubution Network IBO Input Back Off IC-POT Interexchange Carrier-Point of Termination IC Independent Company IC Installation Center IC Integrated Circuit IC Interexchange Carrier ICANN Internet Corporation for Assigned Names and Numbers ICB Individual Case Basis ICC Interface Controller Card ICCB Internet Control and Configuration Board ICCF Industry Carriers Compatibility Forum ICCF Interexchange Carrier Compatibility Forum ICCID Integrated Circuit Card ID (GSM - UMTS) ICD International Code Designator ICI Inter-Carrier Interface (SMDS) ICI Interexchange Carrier Interface (Bellcore) ICID Interexchange Carrier ID ICID Internet Caller IDentification service ICIP Inter-Carrier Interface Protocol ICL Inserted Connection Loss ICLID Incoming Caller Line IDentification ICM Intelligent Call Management ICMP Internet Control Message Protocol ICMP Internet Control Message Protocol (IETF) ICOT Inner City and Outstate Trunk ICP Intelligent Call Processing ICP Internet Control Protocol ICR Intelligent Call Router ICRL Indirect Certificate Revocation List (X.509) ICSC Interexchange Carrier Service Center ICSWE Interexchange Carrier Serving Wire Center ICU ISA Configuration Utility IDB Interface Description Block IDC Internet Data Center IDCP Internet Device Control Protocol IDCT Inverse Discrete Cosine Transform (DCT) IDE Integrated Device Electronics IDE Intelligent Drive Electronics IDEA International Data Encryption Algorithm IDEC Integrated Dynamic Echo Canceller (PictureTel) IDF Intermediate Distributing Frame IDF Intermediate Distributing/Distribution Frame IDI Initial Domain Identifier (ISO) IDLC Integrated Digital Loop Carrier IDN Integrated Digital Network IDN International Data Number (X.121) IDNX Integrated Digital Network Exchange IDP Initial Detection Point (GSM - UMTS) IDP Initial Domain Part IDP Internet Datagram Protocol IDPR Interdomain Policy Routing IDR Internet Detail Record IDS Information Display System (BISYNC) IDS Intrusion Detection System IDT Information Distribution Company IDT Integrated Digital Terminal IDU Interface Data Unit IE Information Element (ISDN/B-ISDN DSS) IEA International Ergonomics Association IEC InterExchange Carrier IEC International Electrotechnical Commission IEEE Institute of Electrical & Electronics Engineers IEEE Institute of Electrical and Electronics Engineers IESG Internet Engineering Steering Group IETF Internet Engineering Task Force IF Intermediate Frequency IFA IP Floating Address IFC Installed First Cost IFR Item for Resolution IFRB International Frequency Registration Board IG Interface Group IGES Initial Graphics Exchange Specification IGMP Internet Group Management Protocol IGOSS Industry/Government Open Systems Specification IGP Interior Gateway Protocol (IETF) IGRP Interior Gateway Routing Protocol (Cisco) IHL Internet Header Length (IP) IIHSO Intercompany Interconnection Held Service Order IIME Intra-network, Inter-SSS Mapping Entity IIS Internet Information Server IISO Intercompany Interconnection Service Order IIT Interactive Information Technology IKE Internet Key Exchange ILD Injection Laser Diode ILEC Incumbent Local Exchange Carrier ILEC Independent Local Exchange Carrier ILMI Interim Local Management Interface iLO Integrated Lights-Out (HP) ILP IntraLATA Presubscription IM Instant Messaging IM Intensity Modulation IMA International Multimedia Association IMA Inverse Multiplexing over ATM IMAP4 IMAP version 4 IMAP4 Internet Message Access Protocol 4 IMAP Internet Messaging Access Protocol IMD Integrated Management Display IMDB In-Memory Data Base IMEI International Mobile Equipment Identity (GSM - UMTS) IMG Industry Markets Group IML Incoming Matching Loss IML Integrated Management Log IML Integrated Management Log (HP) IMP Interface Message Processor(s) IMS Interactive Multimedia Server IMS Interface Management System IMSI International Mobile Subscriber Identity (GSM - UMTS) IMT Inter-Machine Trunk IMTC International Multimedia Teleconferencing Consortium IMTS Improved Mobile Telephone Service IMUX Intelligent Multiplexer IMUX Inverse Multiplexer IN Ingress Node IN Intelligent Network (AIN) IN Interface Network INA Information Network Architecture INA Interactive Network Adapter INAP Intelligent Network Application Part/Protocol (SS7) INB Install Busy INC Industry Numbering Committee INCRP Intelligent Network Call Routing Protocol INE Intelligent Network Element INL Internodal Link INMARSAT INternational MARitime Satellite Service INP Interim Number Portability INP Internet Nodal Processor INPA Interchangeable Numbering Plan Area INPG Industry Number Plan Guide INR Information Request Message INS Information Network System INWATS INward Wide Area Telephone Service IO Inter-Office IOC Inter-Office Channel IOCC I/O Channel Controller IOP Input/Output Processor IOS Internet Operating System (Cisco) IP Information Provider IP Intelligent Peripheral (AIN) IP Internet Protocol (IETF) IPABX ISDN PABX IPAC ISDN PC Adapter Circuit IPAT ISDN Primary Access Transceiver IPC Inter Process Communication IPCP IP Control Protocol IPI Intelligent Peripheral Interface IPL Initial Program Load IPM Interpersonal Messaging System IPPI IP Plug-in IPR Intellectual Property Rights IPS Instructions Per Second IPSec IP Security IPSO IP Security Option IPSS Inter-Processor Signaling System IPX Internetwork Packet Exchange (NetWare) IPXCP IPX Control Protocol IPXWAN IPX Wide-Area Network IR Infra-Red IR Ingress Router IR Instruction Register IR Intermediate Reach IR Internet Registry IRB Integrated Routing and Bridging IRD Implementation Rate Design IRD Integrated Receiver Decoder IrDA Infra red Data Association IRDP ICMP Router Discovery Protocol IRDS Information Resource Dictionary System IRM Inherited Rights Mask IRN Intermediate Routing Node IRP Individual Routing Processor IRPC ISDN Remote Power Control IRQ Information Request (RAS) IRQ Interrupt ReQuest IRR Information Request Response (RAS) IRSG Internet Research Steering Group IRTF Internet Research Task Force IS-IS Intermediate System-Intermediate System (ISO) IS41 Interim Standard 41 IS In-Service IS Information Systems IS Interim Standard (ISO) IS Intermediate System (ISO) ISA Industry Standard Architecture ISAC ISDN Subscriber Access Controller ISAKMP Internet Security Association and Key Management Protocol ISAM Index Sequential Access Method ISC Industry Service Center ISCP Integrated Service Control Point ISDN Integrated Services Digital Network ISDNUP Integrated Services Digital Network User Part ISDNUP ISDN User Part ISI USC Information Sciences Institute ISID Idle Signal Identification ISL Inter-Switch Link (Cisco) ISLAN Integrated Services LAN (IEEE 802.9) ISLU ISDN Line Unit (AT&T 5ESS) ISM Industrial, Scientific, Medical ISM Internetwork Status Monitor ISN Information Systems Network ISO International Organization for Standardization ISO International Standards Organization ISP Intermediate Service Part ISP Internet/Information Service Provider ISPC International Signaling Point Code ISR Interconnection Service Request ISR Intermediate Session Routing ISSI Inter-Switching System Interface (SMDS) ISSIP Inter-Switching System Interface Protocol ISSN Integrated Special Services Network ISU Iridium Subscriber Unit ISUP ISDN Services User Part ISUP ISDN User Part (SS7) ISV Independent Software Vendor IT Information Technology IT Information Type ITA Interactive TV Appliances ITAC-T International Telecommunications Advisory Committee-Telecommunications ITAC ISDN Terminal Adaptor Circuit ITB Intermediate Text Block (BISYNC) ITC Independent telephony company ITCM Integrated Telephony Cable Modem ITFS Instructional Television Fixed Services ITG Interswitch Trunk Group ITGS Intelligent Traffic Guidance Systems ITN Independent Telecommunication Network ITSP Internet Telephony Service Provider ITU-D ITU-Telecommunication Development Sector (formerly BDT) ITU-R ITU-Radio Communication Sector (formerly CCIR and IFRB) ITU-T ITU-Telecommunication Standardization Sector (formerly CCITT) ITU International Telecommunication(s) Union ITU International Telecommunications Union ITV Interactive TeleVision IUM Internet Usage Manager IV Initialization Value IV Interactive Video IVD Internal Vapor Deposition IVDM Integrated Voice Data Multiplexer IVDS Interactive Video and Data Services (ITA) IVR Interactive Voice Responder IVS Interactive Video Services IVS Interactive Video System IVTTA Intelligent Vehicle and Transportation Technical Area IW Inside Wire IWF Inter-Working Function IWF Interworking Connection IWU Inter-Working Unit (B-ISDN) IWX Interworking Function IX IntereXchange IXC Inter-Exchange Carrier IXC IntereXchange Carrier IXVG IntereXchange Voice Grade channel JAIN JAVA APIs for Integrated Networks JIS Jurisdictional Interstate Service JIT Just in Time JPEG Joint Photographic Experts Group JPEG Joint Photographic Experts Group (ISO) JRE Java Runtime Environment JTA Java Transaction API JTAPI Java Telephony API JTM Job Transfer and Management JUNET Japan UNIX Network JVM Java Virtual Machine K Kilo- KBPS / KB/s KiloBits Per Second KBPS KiloBits Per Second KCPS KiloCycles Per Second KHZ KiloHertZ KM KiloMeter KP Key Pulse KPI Key Performance Indicator KTS Key Telephone System KWH KiloWatt Hour LAA Longest Available Agent LAC Location Area Code LAC Location Area Code (GSM - UMTS) LAC Loop Assignment Center LADS Local Area Data Service LADT Local Area Data Transport LAI Location Area Identity (GSM) LAMA Local Automatic Message Accounting LAN-PHY LAN Physical Layer LAN Local Area Network LANE Local Area Network Emulation LANS Local Area Network Services LAP-B Link Access Protocol Balanced LAP-D Link Access Protocol-D channel LAP Link Access Procedure (X.25) LAP Link Access Protocol LAPB Link Access Procedure Balanced (X.25) LAPD Distributed Link Access Procedure LAPD Link Access Procedure for the D-channel (ISDN) LAPF Link Access Procedure to Frame Mode Bearer Services (FR, ISDN) LAPM Link Access Procedure for Modems (V.42) LAPS Local Access ProcedureS LAPX Link Access Procedure half-duplex (X.32) LARG LIDB Access Routing Guide LASS Local Access Signaling Services LASS Local Area Signaling Services LAT Local Area Transport (DEC) LATA Local Access and Transport Area LAVC Local Area VAX Cluster (DEC) LAW Local Area Wireless LBS Location Based Services LBT Listen Before Talk LC Load Coil LC Local Competition LC Logical Channel LC Loop Closure LCA Line Circut Address LCC Line Class Code LCD Liquid Crystal Diode/Display LCD Liquid Crystal Display LCF Location Confirm (RAS) LCF Loop Current Feed LCFO Loop Current Feed Open LCGN Logical Channel Group Number (X.25) LCM Line Concentrator Module LCN Logical Channel Number (X.25) LCP Link Control Protocol LCR Least Cost Routing LCS Location Services LD Laser Diode LD Local Directory LD Long Distance LDAP Lightweight Directory Access Protocol LDAP Lightweight Directory Access Protocol (Protocol) LDAPIF LDAP Interface Module (SZ) LDC LATA Distribution Channel LDDI Local Distributed Data Interface (ANSI) LDF Local Distribution Frame LDI Long Distance Indicator LDM Limited Distance Modem LDN Listed Directory Number LDS Local Digital Switch LDS Long Distance Switching LE/PH Local Exchange/Packet Handler (ISDN) LE Local Exchange (ISDN) LEC LAN Emulation Client LEC Local Exchange Carrier LED Light Emitting Diode LEIF Location Engine Interface (SZ) LEN Length LEN Line Equipment Number LEN Low Entry Networking LEO Low Earth Orbit LEOS Low Earth Orbit Satellite(s) LEOS Low Earth Orbiting Satellite LERG Local Exchange Routing Guide LES LAN Emulation Server LES LAN Emulation Server/Services LESVC Location Engine Service Module (SZ) LET Line Equipment Transfer LF Largest Frame LF Loop Feeder LF Low Frequency LFACS Loop Facility Assignment Control System LFSID Local Form Session Identifier LGC Line Group Controller LH Link Header LI Length Indication LI Length Indicator LI Local Interconnection LIDB Line Information DataBase LIDB Line Information Database (ISDN) LIF Location Interoperability Forum LIF Logger Interface Module (SZ) LIFO Last In First Out LIPX Large Internet Packet Exchange (NetWare) LISA Local Interconnection Service Arrangement LISC Local Interconnection Service Center LIT Line Insulation Test LLAP LocalTalk Link Access Protocol (Apple) LLB Line Loop Back LLC Limited Liability Company LLC Logical Link Control (IEEE 802.2) LLI Logical Link Identifier LLSC signaling Link management, Link Set Control LMC Loop Maintenance Center LMDS Local Multipoint Distribution Service LMDS Local Multipoint Distribution Service/System LMI Local Management Interface LMOS Loop Maintenance Operations System LMS Local Measured Service LMSI Local Mobile Subscriber Identity (GSM) LMSS Land Mobile Satellite Service LMTS Lead Member of Technical Staff LMU Line Monitor Unit LNP Local Number Portability LO Loop Open LO Low Order LOC Local Operations Center LOCREQ Location Request LOF Loss Of Frame LOH Line Overhead (SONET) LOM Lights-Out Management LOP-L Loss Of Pointer-Line LOP-P Loss Of Pointer-Path LOP-V Loss Of Pointer-Virtual LOP Line of Position LOP Loss Of Pointer LOS Line of Sight LOS Loss Of Signal LOSW Loss Of Synchronous Word LP Link Printer LPC Linear Predictive Coding LPD Link Protocol Discriminator (GSM) LPDA2 Link Problem Determination Aid 2 (IBM) LPDP Local Policy Decision Point LPIC Local Primary Interexchange Carrier LPP Lightweight Presentation Protocol LPP Link Peripheral Processor LPU Line Protection Unit LPVS Link Packetized Voice Subsystem LRB Loop Reverse Battery LRC Longitudinal Redundancy Check LRC Longitudinal Redundancy Check (BISYNC) LRJ Location Reject (RAS) LRN Local Routing Number LRQ Location Request (RAS) LS Link State LS Loop Start LSAC signaling Link management, Signaling Link Activity Control LSAP Link Service Access Point LSB Least Significant Bit LSC Link State Control LSC Local Service Center LSI Large Scale Integration LSL Link Support Layer LSLA signaling Link management, Signaling Link Activation LSLD signaling Link management, Signaling Link Deactivation LSLR signaling Link management, Signaling Link Restoration LSMS Local Service Management System LSNE Local Switching Network Element LSNP Local Switching with Number Portability LSO Local Serving Office LSOA Local Service Order Administration LSP Local Service Provider LSR Local Service Request LSSGR LATA Switching and Signalling Generic Requirements LSSU Link Status Signal Unit (GSM) LSU Line Switch Unit LT Line Termination LT Link Trailer LT Local Transport LTD Local Test Desk LTE Line Terminating Equipment (SONET) LTG Line Trunk Groups LU Line Unit LU Location Update LU Logical Unit LU Logical Unit (SNA) LULT Line Unit/Line Termination LUNT Line Unit Network Termination LXT Local Exchange Terminal M&P Methods & Procedures M2UA MTP3 User-Adaptation Layer M3UA MTP2 User-Adaptation Layer M Mega M Modem MA Maintenance Administrator MAA Maximum Availability Architecture (Database) MAC Media Access Control MAC Media Access Control (IEEE 802) MADN Multiple Appearance Directory Number MAN Metropolitan Area Network Management System MAP/TOP Manufacturing Automation Protocol/Technical and Office MAP Maintenance Administration Panel MAP Management Application Protocol MAP Manufacturing Automation Protocol MAP Manufacturing Automation Protocol (GM) MAP Mobile Application Part MAP Mobile Application Part (GSM - UMTS) MAPDU Management Application Protocol Data Unit MAPI Mail Application Programming Interface MAR Memory Address Register MAT Metropolitan Area Trunk MAU Medium Attachment Unit (Ethernet) MAU Multistation Access Unit MAU Multistation Access Unit (Token Ring) MB Maintenance Busy MB Message Buffer MBG Multi-switch Business Group MBI-A Message Based Interface Adapter (HP) MBI Message Based Interface MBPS Mega Bits Per Second MBS Mobile Broadband Systems MC/SG MC/Service Guard (HP) MC Maintenance Center MC Message Center MC Multipoint Controller MCA MicroChannel Architecture (IBM) MCC Microelectronics & Computer technology Co. MCC Mobile Country Code MCC Mobile Country Code (GSM - UMTS) MCGA Multi-Color Graphics Array MCI Microwave Communications, Inc. MCPA Multi Carrier Power Amplifier MCPC Multiple Channel Per Carrier MCR Minimum Cell Rate (ATM) MCS/AS Media Control Server/Application Server MCS/MS Media Control Server/Management Server MCS Media Control Server MCU Master Control Unit MCU Multiplexer Control Unit MCU Multipoint Control(ler) Unit MCVD Modified Chemical Vapor Deposit MDB Management Database MDBS Mobile DataBase Station MDCP Media Device Control Protocol MDF Main Distribution Frame MDI Medium-Dependent Interface MDIS Mobile Data Intermediate Station MDNS Message Delivery to NonSubscriber MDR Memory Data Register MDR Message Detail Recording MDS Multipoint Distribution Service MDT Mobile Data Terminal MDTP Media Device Transport Protocol MDU Multiple Dwelling Unit ME Mobile Equipment (GSM - UMTS) MED Modem Equivalent Device MEGACO Media Gateway Control Protocol MEO Medium Earth Orbit MEOS Medium Earth Orbit Satellites MF Main Frame MF Media Filter MF Medium Frequency MF More Fragments (IP) MF Multiple Frequency MFAS Multi-Frame Alignment Signal MFJ Modified Final Judgement MFJ Modified Final Judgment MFLOPS Millions of Floating point Operations Per Second MFS Metropolitan Fiber Systems MFSK Multiple Frequency Shift Keying MG Media Gateway MGC/MG Media Gateway Controller/Media Gateway MGC Media Gateway Controller MGCP Media Gateway Control Protocol MGW Mini-Gateway Prototype MHS Message Handling System MHS Message Handling System (X.400) MHZ MegaHertZ MIB Management Information Base MIB Management Information Base (Network Mgmt.) MIC Medium Interface Connector (FDDI) MICA Multiservice IOS Channel Aggregation (Cisco) MID Message IDentifier MID Message Identifier (ATM, SMDS) MID Multiplexing Identifier (ATM) MIDI Musical Instrument Digital Interface MIDP Mobile Information Device Profile MIF Management Information Format MIF Mobile Interface Module (SZ) MIMD Multiple Instruction stream, Multiple Data stream MIME Multipurpose Internet Mail Extensions (IETF) MIME Multipurpose Internet Mail Extentions MIN Mobil Identification Number MIN Mobile Identification Number MIP MultiChannel Interface Processor (Cisco) MIPS Millions of Instructions Per Second MIS Management Information Systems MIT Massachusettes Institute of Technology MITI Ministry of International Trade and Industry (Japan) MIX Multimedia Internet Exchange MJU Multi-Junction Unit MLAC Mechanized Loop Assignment Center MLC Mobile Local Call MLC Multilink Control Field (X.25) MLHG Multi-Line Hunt Group MLID Multiple Link Interface Driver MLM Multi-Longitudinal Mode MLN Main Listed Number MLP Multi-Layer Protocol MLP Multilink Protocol (X.25) MLS Multiple Listing Service MLT Mechanized Loop Testing MLT Metalic Loop Test MM Mobility Management (GSM) MM Multi Media MM Multi Mode MMC Microsoft Management Console MMDS Multichannel Multipoint Distribution Service MMDS Multimedia Data Services MMF Multimode Fiber MMI Man Machine Interface MML Man Machine Language MMS Manufacturing Message Specification MMS Multimedia Messaging Service MMSC Multimedia Messaging Service Centre MMSK Modified Minimum Shift Keying MMU Memory Management Unit MNC Mobile Network Code (GSM - UMTS) MNO Mobile Network Operator MNPVC Multinetwork PVC (FR NNI) MO Managed Object MO Mobile Originated (GSM - UMTS) MOC Managed Object Classes MOC Mobile Originated Call MODEM MOdulator/DEModulator MOM Manager of Managers MOOS Manual Out-OF-Service MOP Maintenance Operations Protocol MOSFET Metal Oxide Semiconductor Field Effect Transistor MOU Minutes Of Use MP Multipoint Processor MPB Meet Point Billing MPEG Motion Picture Experts Group (ISO) MPEG Moving Picture Experts Group MPLS Multi-Protocol Label Switching MPoA Multiple Protocol over ATM MPOP Minimum Point of Penetration (wire) MPR Multiprotocol Router MPS Multi-Processor Specification MPTN Multiprotocol Transport Network MPX Multiprocessor Extension MRCP Media Resource Control Protocol MRF Multilink Frame Relay MRI Magnetic Resonance Imaging MRVT MTP Routing Verification Test MS Management System MS Message Store MS MilliSecond MS Mobile Station MS Mobile Station (GSM) MSA Management System Architecture MSA Metropolitan Serving Area MSA Metropolitan Statistical Area MSAG Master Street Address Guide MSB Most Significant Bit MSC Media Stream Container MSC Mobile Switching Center MSCT Message Set customization Tool MSD Marketing Service Description MSDM Multipoint Substrate Data Mux MSG Message MSISDN Mobile Station (international) ISDN number MSISDN Mobile Station Integrated Services Digital Network (GSM - UMTS) MSK Minimum Shift Keying MSO Mobile Switching Office MSO Multiple Service/Systems Operator MSP Marketing and Sales Productivity MSRN Mobile Station Roaming Number (GSM) MSS Maximum Segment Size (TCP) MSS Mobile Satellite Services MSS Mobile Satellite Systems MST Multislotted Token MSU Message Signal(ling) Unit MSVC Meta-Signaling Virtual Channel MT&T Maritime Telegraph and Telephone MT Mobile Terminated (GSM - UMTS) MTA Major Trading Area(s) MTA Message Transfer Agent MTAU Metalic Test Access Unit MTBF Mean Time Between Failures MTC Mobile Terminated Call MTF Modulation Transfer Function MTP Message Transfer Part MTP Message Transfer Part (SS7) MTP Message Transfer Port MTS Member of Technical Staff MTS Message Telecommunications MTS Message Telephone System MTSO Mobil Telephone Switching Office MTSO Mobile Telephone Switching Office (Cellular) MTTR Mean Time To Repair MTU Maximum Transfer Unit MTU Maximum Transmission Unit (TCP) MUB MultiUse Bearer service MULDEM MULtiplexer/DEMultiplexer MUX MUltipleXer MVIP Multivendor Integration Protocol MVNO Mobile Virtual Network Operator MVPN Mobile Virtual Private Network MVS Multiple Virtual Storage MWI Message Waiting Indicator N-AMPS Narrowband AMPS NA-TDMA North American Time Division Multiple Access NA Numerical Aperture NAA Next Available Agent NAA Number Assignment Administration NABER National Association of Business and Educational Radio NAC National Access Code NAC Network Administration Center NAC Null Attachment Concentrator (FDDI) NAC Number Assignment Center NACK Negative ACKnowledgement NADH North American Digital Hierarchy NAK Negative Acknowledgement (BISYNC, DDCMP) NANC North American Numbering Council NANP North American Number Plan NANP North American Numbering Plan NAP Network Access Point NAP Network Access Point (Internet) NAPLS North American Presentation Level protocol Syntax NAR Network Access Restriction NARUC National Association of Regulatory Utilities Commissions NAS Netowrk Access Server NAS Network Application Support NAS Network Attached Storage NASA National Aeronautics and Space Administration NASDAQ National Association of Securities Dealers Automated Quotations NAT Network Address Translation NAT Network Attached Storage NATA North American Telecommunications Association NAU Network Access/Addressable Unit NAU Network Accessible Unit (SNA) NB Normal Burst NBP Name Binding Protocol (NetWare) NBS National Bureau of Standards (old) NC Network Channel NC Number of unallocated channels at node NCA Non-Call Associated NCC Network Color Code NCC Network Colour Code (GSM - UMTS) NCC Network Communications Controller NCCF Network Communication Control Facility NCI Network Channel Interface NCIA Native Client Interface Architecture (Cisco) NCP NetWare Core Protocol (NetWare) NCP Network Control Point/Program NCP Network Control Point/Protocol NCP Network Control Program (SNA) NCS Network Computing System NCSA National Center for Supercomputing Applications NCTA National Cable Television Association NCTE Network Channel Terminating Equipment NCTE Network Channel Termination Equipment NDC National Destination Code NDF New Data Flag NDIS Network Device Interface Specification NDIS Network Driver Interface Specifications (Microsoft & 3Com) NDS Netware Directory Services NE Network Element NEARnet New England Academic and Research Network NEAT Network Expert Advisory Tool (Harris Corp.) NECA National Exchange Carriers Association NENA National Emergency Number Association NET Norme Europeenne de Telecommunications NETID Network Identifier NEXT Near End Cross Talk NFAS Non-associated Facility Signaling NFAS Non-Facility Associated Signaling NFAS NonFacility Associated Signaling NFS Network File System NFS Network File System (Sun) NGDLC Next Generation Digital Loop Carrier NGN Next Generation Network NGW Network Gateway NI National ISDN NI Network Interconnect NI Network Interface NIC Network Information Center NIC Network Interface Card (LAN) NIC Network Interface Controller NICE Network Information and Control Exchange NID Network Interface Device NII National Information Infrastructure NIST National Institute of Standards and Technology NIU Network Interface Unit (T-carrier) NIUF N.A. ISDN User Forum NIUF North American ISDN Users Forum NL Network Layer NL Number of unallocated channels on link NLDM Network Logical Data Manager NLM NetWare Loadable Module NLOS Near Line of Sight NLPID Network Layer Protocol Identifier NLSP NetWare Link Services Protocol NM Network Management NM Network Module NM Node Manager workstation NMA Network Management and Administration NMA Network Monitoring and Analysis NMC Network Management Center NMCC Network Management Control Center NMI Non-Maskable Interrupt NML Network Management Layer NMP Network Management Processor (Cisco) NMP Network Management Protocol NMR Network Measurement Report (GSM - UMTS) NMS Network Management Station (OAM) NMS Network Management System NMT Nordic Mobile Telephone system NMVT Network Management Vector Transport protocol NN Network Node NNA Network Node Address NNI Network Node Interface (ATM) NNI Network-to-Network Interface (FR) NNTP Network News Transfer Protocol NNTP Network News Transfer/Transport Protocol NOC Network Operations Center NOCC Network Operations Control Center NOP No Operation NOS Network Operating System NOTE Network Office Terminating Equipment NPA Numbering Plan Area NPAC Number Portability and Administrative Center NPAS Network Portability Access Service NPD Non-Payment Disconnect NPDA Network Problem Determination Application NPDU Network Layer Protocol Data Unit NPDU Network Protocol Data Unit NPI Numbering Plan Identification NPRM Notice of Proposed RuleMaking NPRN Network Performance Report Message NPSI NCP Packet Switching Interface (SNA) NRC Non Recurring Charge NREN National Research & Education Network NREN National Research and Education Network NRF New Regulatory Framework NRIC National Reliability and Interoperatability Council NRS Number Referral Service NRZ Non-Return to Zero NRZ NonReturn to Zero NRZI Non-Return to Zero Inverted NRZI NonReturn to Zero Inverted NS/DOS Networking Services/DOS NS Network Service NSA National Security Agency NSA Non-Service Affecting NSAP Network Service Access Point (ISO) NSC Network Service Center NSF National Science Foundation NSF Network Specific Facilities NSFNET National Science Foundation NETwork NSI Network Service Interface NSP National Signaling Point NSP Network Service(s) Protocol NSP Network Services Protocol NSS Network Switching Subsystem NSVC Network Service Virtual Circuit NT Network Terminal NT Network Termination (ISDN) NT New Technology (Windows) NT Node Type NTAS New Technology Advanced Server (Microsoft) NTE Network Terminating Equipment NTG Network interface Trunk Group NTN Network Terminal Number NTN New Telephone Number NTO Network Terminal Option NTSC National Television System Committee NTT Nippon Telephone and Telegraph NTT Numbered Test Trunk NTW Network Terminating Wire NUI Network User Identification (X.25) NUI Network User Identifier NVE Network-Visible Entities NVOD Near Video On Demand NVRAM Nonvolatile Random Access Memory (RAM) 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&M Operation, Administration and Maintenace OA Operator Assistance OACSU Off-air Call Setup (GSM) OADM Optical Add-Drop Multiplexer OAI Open Access Interconnection OAM&P Operation, Administration, Maintenance & Provisioning OAM&P Operation, Administration, Maintenance and Provisioning OAM Operation, Administration and Maintenance OANAD Open Access Network Architecture Development OBF Ordering & Billing Form OBO Output Back Off OBP On Bord Processing OC&C Other Charges & Credits OC-NMS HP OpenCall Network Media Server. Plays the role of IVR in the HP/Sicap PrePaid IN solution OC-SAC HP OpenCall Service Access Controller OC3 Optical Carrier 3 OC Operating Company OC Operation Code OC Optical Carrier (SONET) OCAL Opencall Layer (HP) OCC Other Common Carrier(s) OCC Outgoing Call Control service OCCA Open, Cooperative Computing Architecture OCCI Oracle C++ Call Interface (Database) OCI Oracle Call Interface (Database) OCMC Opencall Multiservice Controller OCMP-BRE OCMP Browser Runtime Environment (HP) OCMP-BRE OpenCall Media Platform Browser Runtime Environment (HP) OCMP OpenCall Media Platform (HP) OCP Optional Calling Plan OCPD Over Current Protection Device OCR Optical Character Recognition OCSAC OpenCall Service Access Controller OCSC OpenCall Service Controller OCU Office Channel Unit OCUDP Office Channel Unit Data Port ODA Open Document Architecture ODBC Open Data Base Connectivity ODBC Open Database Connectivity ODI Open Data-link Interface (Novell) ODIF Open Document Interchange Format OE Office Equipment OE Originating Equipment OEM Original Equipment Manafacturer OEM Original Equipment Manufacturer OEO Optical-Electrical-Optical OFA Optical Fiber Amplifier OFDM Orthogonal Frequency Division Multiplexing OHD Off-Hook Delay trigger OID OAM Object Identifier OID Object Identifier OID Oracle Internet Directory (Database) OIM Operations Interface Module OLAP Online Application Processing (Database) OLC Optical Loop Carrier OLE Object Linking and Embedding OLNS Originating Line Number Screening OLP On-Line Provisioning OLTM Optical Line Termination Multiplexer OLTP OnLine Transaction Processing OLTP Online Transaction Processing (Database) OM Operational Measurement OMAP Operations & Maintenance Application Part OMAP Operations, Maintenance, and Administration Part (SS7) OMC-R The radio OMC OMC-S The switching OMC OMC Operations and Maintenance Center OML Operation and Maintenance Link (GSM) ONA Open Network Architecture ONA Order Number Administration ONC Open Network Computing ONI Operator Number Identification ONMS Open Network Management System ONP Optical Network Planner (Cisco) ONU Optical Network Unit OO Object-Oriented OOD Object Oriented Design OODBMS Object Oriented DabaBase Management System OOF Out Of Frame OOP Object-Oriented Programming OOPS Object-Oriented Programming System OOS Out Of Service OOS Out Of Synchronization OPC Origination Point Code (SS7) OPI Open Peripheral Interface (Cisco) OPN Outage Performance Monitoring OPS/INE Operations System/Intelligent Network Element OPS Oracle Parallel Server OPT Cisco's Open Packet Telephony architecture OPX Off Premise Extension OR Office Regenerator ORB Office Repeater Bay ORCA Option ROM Configuration for Arrays ORCA Option ROM Configuration for Arrays (HP) ORM Optically Remote switching Module ORT Operational Readiness Testing OS Operating System OSA Open System Architecture OSF Open Software Foundation OSI/CS OSI/Communications Subsystem OSI/FS OSI/File Services OSI/NMF OSI/Network Management Forum OSI Open Systems Interconnection OSI Open Systems Interconnection (ISO, ITU-T) OSINET OSI Network OSIRM Open Systems Interconnection Reference Model (ISO, ITU-T) OSLP Operational Service logic Program OSO Originating Screening Office OSO Origination Screening Office OSP Operator Service Provider OSP OutSide Plant OSPF Open Shortest Path First (IETF) OSS Operation(s)/Operational Support System OSS Operational Support Systems OSS Operator Services System OTA Over The Air OTA Over The Air (GSM - UMTS) OTDR Optical Time Domain Reflectometer OTF Open Token Foundation OTGR Operations Technology Generic Requirement OTIS Optical Transport Interconnection Service OU Organizational Unit OUI Organizationally Unique Identifier (SNAP) OV Overload OVD Outside Vapor Deposition OVw OpenView Windows P/AR Peak to Average Ratio P/F Poll/Final Bit P2P Peer-To-Peer PA Pointer Adjustment PA Preamble (LAN) PA PreArbitrated PABX Private Automatic Branch Exchange PACS Personal Access Communication System PAD Packet assembler/disassembler (GSM) PAD Packet Assembler/Disassembler (X.25) PAD Packet Assembly-Disassembly PAL Phase Alternate Line PAM Pass Along Message PAM Pulse Amplitude Modulation PAMR Public Access Mobile Radio PANS Pretty Amazing New Services (B-ISDN) PAP Printer Access Protocol PAP Process/Application Protocol PAP Public Access Profile (DECT) PAR Positive Acknowledgement with Retransmission PAR Prompted Auto-Redial service PARC Xerox Palo Alto Research Center PASP Public Service Answering Point PAW Personal Area Wireless PBD Power Board PBX Private Branch Exchange PC Personal Computer PC Point Code PC Program Counter PCA Plug-In Comunication API PCB Printed Circuit Board PCB Process Control Block PCF Point Coordination Function PCH Paging Channel (GSM) PCI Peripheral Component Interconnect PCI Peripheral Components Interface PCI Protocol Control Information PCIO Program Controlled I/O PCM Pulse Code Modulation PCMCIA Personal Computer Memory Card Interface Association PCN Personal Communications Network PCNE Protocol Converter for Non-SNA Equipment PCR Peak Cell Rate (ATM) PCS-1900 Personal Communications Systems 1900MHz PCS Personal Communications Services PCTF Per-Call Test Failure PCU Packet Control Unit PCU Premises Control Unit PD Premier Dialing PD Propagation Delay PD Protocol Discriminator (GSM) PDA Personal Data/Digital Appliance/Assistant PDA Personal Digital Assistant PDC Personal Digital Communications PDC Power Distribution Center PDF Portable Document Format PDF Portable Document Format] PDH Plesiochronous Digital Hierarchy PDI-P Payload Defect Indicator-Path PDI-V Payload Defect Indicator-Virtual PDM Physical Medium Dependent (FDDI) PDN Public Data Network PDP Packet Data Protocol PDP Policy Decision Point PDS Premises Distribution System PDU Power Distribution Unit PDU Protocol Data Unit PEDC Pan European Digital Communications PEL Picture Element PEP Partitioned Emulation Program PEP Policy Enforcement Point PER Packed Encoding Rules PF Polycenter Framework PFDL Policy Framework Definition Language PFM Packet Forwarding module PG Peripheral Gateway PGS Pair Gain System PGTC Pair Gain Test Controller PH Packet Handler (ISDN) PHS Packet Handling System PHS Personal Handy Phone System (Japan) PHY-PCI Physical Layer-Protocol Control Information PHY-SAP Physical Layer-Service Access Point PHY-SDU Physical Layer-Service Data Unit PHY Physical Layer PHYM Physical Layer Management PI Plug-In PI Process Improvement PIB Policy Information Base PIC Plug-In Container PIC Point In Call PIC Primary Interexchange Carrier PIC Programmable Interrupt Controller PICC Prescribed Interexchange Charge PICC Primary Interexchange Carrier Charge PID Path Identification PIG Proprietary Information Guidelines (legal document PIM Peripheral Interface Manager (Cisco) PIM Product Integration Manager PIN Personal Identification Number PIN Positive Intrinsic Negative PINS Plug-In Network Sensor PIP Pre-Impulsing Pulse PIT Process Integration Testing PIU Path Information Units (SNA) PJC Pointer Justification Count PKI Public Key Infrastructure PKI Public Key software Infrastructure PL/SQL Procedural Language/Structured Query Language (Database) PL Private Line PLA Programmable Logic Array PLAR Private Line Automatic Ringdown PLB Payload Loop Back PLC Power Line Carrier PLCP Physical Layer Convergence Protocol (DQDB) PLIM Physical Layer Interface Module (Cisco) PLMN Public Land Mobile Network PLMN Public Land Mobile Network (GSM - UMTS) PLP Packet Layer Protocol (X.25) PLP Presentation Level Protocol PLS Private Line service PLU Percentage Local Usage PLU Primary Logical Unit PM Performance Monitoring PM Peripheral Modules PM Phase Modulation PM Physical Medium PM Privacy Manager service PMA Physical Medium Attachment PMC PCI Mezzanine Card PMD Physical Medium Dependent (FDDI) PMR Private Mobile Radio(communications) PMTS Principal Member of Technical Staff PNNI Private Network Node Interface PNS Packet Switching Node POC Positive Outage Control POCSAG Post Office Code Standardisation Group POD Programmable Option Devices POF Pending Order File POH Path Overhead (SONET) POI Point of Interconnection PON Passive Optical Network POP3 Post Office Protocol 3 POP Point Of Presence PoP Points of Presence POP Post Office Protocol PoS Packet Over SONET POS Point Of Sale POSI Promotion of OSI POSIT Profiles for Open Systems Interworking Technologies POSIX Portable Operating System Interface for UNIX POST Power-On Self Test POST Power-On Self-Test POT Point Of Termination POTS Plain Old Telephone Service POTS Plain Old Telephone Service/System POTS Plain Old Telephony Service PP Payload Pointer PPB PrePaid Billing (Sicap) PPC PrePaid Core (Sicap) PPD Parallel Presence Detect PPD Preferred Payment Date PPD Project Profile Database PPDU Presentation Protocol Data Unit PPM Processor Power Module (HP) PPP Point-to-Point Protocol (IETF) PPS Packets Per Second PPS PrePaid Server PPSN Public Packet Switched Network PPSP PPS Proxy PRA Primary Rate Access PRBS Pseudo-Random Binary Sequence PRBS Pseudo-Random Bit Sequence PRC Primary Reference Clock PRD Prompted Repeat Dial service PRD Pseudo-Random Downstream PREMIS Premises Information System PRI Primary Rate Interface PRI Primary Rate Interface (ISDN) PRM Performance Report Message PROFREQ Profile Request PROFS Professional Office System PROM Programmable Read Only Memory PRS Personalized Response System PRS Primary Reference Source PRS Project Requirements Specifications PRSIG Pacific Rim SMDS Interest Group PRU Pseudo-Random Upstream PS Packet Switch PSAP Primary Safety Answering Point PSB Public Service Board PSC Primary Scrambling Code (GSM - UMTS) PSC Public Service Commission PSD Product Specification Document PSDM Premium Substrate Data Mux PSDN Packet Switched Data Network PSDN Public Switched Data Network PSDS Public Switched Data Services PSDS Public Switched Digital Service PSELFEXT Power Sum Equal Far End Cross Talk PSI Packet Switching Interface (DNA) PSI Performance Systems International PSK Phase Shift Keying PSN Alternative to PSTN (Public Switched Telephone Network) PSNEXT Power Sum Near End Cross Talk PSP ProLiant Support Pack (HP) PSPDN Packet Switched Public Data Network PSPDN Public Switched Packet Data Network PSRCP Public Safety Radio Communications Project PSTN Public Switched Telephone Network PSU Power Supply Unit PSW Program Status Word PSX Power System Exchange PT Payload Type PTE Path Terminating Equipment (SONET) PTI Packet Type Identifier (X.25) PTI Payload Type Identifier (ATM) PTI Payload Type Indicator PTM Packet Transfer Mode PTM Packet Transfer/Transport Mode PTN Personal Telephone Number PTN Public Telephone Network PTO Public Telecommunication Operator PTT Post Telephone & Telegraph admin PTT Push-to-Talk (PMR) PTZ Pan-Tilt-Zoom (Camera) PU Physical Unit PU Physical Unit (SNA) PUC Public Utilities Commission PUK PIN Unblocking Key (GSM) PVC Permanent Virtual Circuit/Connection PVN Private Virtual Network PVT Product Validation Testing PWT Personal Wireless Telecommunications PXE Preboot eXecution Environment PZN PersonaliZed telephone Number QA Quality Assurance QA Queue Arbitrated QAM Quadature Amplitude Modulation QAM Quadrature Amplitude Modulation QAPSK Quadrature Amplitude Phase Shift Keying QASPR QUALCOMM Automatic Satellite Position Reporting QBE Query By Example QCELP Quadrature Code Excited Linear Prediction QCIF Quarter Common Intermediate Format QDT Quick Dial Tone QER Q.931 Encoding Rules QLLC Qualified Logical Link Control (SNA) QoE Quality of Experience QoR Query on Release QoR Query on Response QOS Quality of Service QPA Quality Performance Analysis QPM QoS Policy Manager (Cisco) QPSK Quadrature Phase Shift Keying (DQDB) QPSX Queued Packet and Sychronous eXchange QRS Quasi Random Signal QRSS Quasi Random Signal Sequence QTAM Queued Telecom Access Method R5 Release 5 of the 3GPP standards (GSM - UMTS) R6 Release 6 of the 3GPP standards R Ring R Router RAC Real Application Cluster RAC Real Application Cluster (Database) RAC Resource Available Confirmation RACE Research in Advanced Communications in Europe RACF Remote Access to Call Forwarding RACH Random Access Channel (GSM) RAD Receive Adress RAD Remote Antenna Driver RADIUS Remote Authentication Dial-In User Service RADN Remote Access Dialing Number RAI Remote Alarm Indication RAI Resource Available Indication RAID Redundant Array of Inexpensive/ Independent Disks RAID Redundant Array of Inexpensive/Independent Disks RAL Resale Access Line RALB Resource All Busy RAM Random Access Memory RAO Revenue/Regional Accounting Office RARP Reverse Address Resolution Protocol (IETF) RAS Registration, Admission, and Status RAS Registration, Admission, Status RAS Remote Access Server/Service RASP Remote Antenna Signal Processing RAT Radio Access Technology (GSM - UMTS) RBEF Read Block Error counter for Far end RBEN Read Block Error counter for Near end RBOC Regional Bell Operating Company RBS Robbed Bit Signaling RBSU ROM-Based Setup Utility RBSU ROM-Based Setup Utility (HP) RC Radio Control RC Receiver Signal Element Timing (EIA-232-E) RC Recurring Charges RC Retransmission Counter RC Ringing Circuit RCA Radio Corporation of America RCC Radio Common Carrier RCC Reverse Control Channel RCE Remote Channel Extenders RCF Registration Confirm (RAS) RCF Remote Call Forwarding RCF Routing Control Field RCI Rate Center Inconsistency RCMAC Recent Change Memory Administration Center RCRMS Revenue Collection Risk Management System RCU Remote Cell Unit RCV Receive RCVR Receiver Sequence Number RD Receive Data RD Received Data (EIA-232-E) RD Request Disconnect (HDLC) RD Routing Domain RDAC Remote Digital Access Center RDBMS Relational DabaBase Management System RDC Regional Data Center RDF Remote Distribution Frame RDF Route Designator Field RDI-L Remote Defect Indicator-Loop RDI-P Remote Defect Indicator-Path RDI-V Remote Defect Indicator-Virtual RDI Remote Defect Indicator RDMS Relational Database Management System (Database) RDP Remote Desktop Protocol RDPL Remote Desktop Protocol RDSS Radio Determination Satellite Service RDT Remote Digital Terminal RDTD Restricted Differential Time Delay RDU Remote Distribution Unit RE Relaying Entity REC RECeiver REGNOT Registration Notification REJ Reject (HDLC) RELP Regular pulse Excitation Linear Prediction coding REM Ring Error Monitor REN Ringer Equivalent Number REP Repeat RESP Response RET Returning RF Radio Frequency RFA Request For Action RFC Request For Comment RFC Request For Comments (IETF) RFH Remote Frame Handler (ISDN) RFI Radio Frequency Interference RFI Request For Information RFP Radio Fixed Part RFP Request For Proposal RFQ Request For Quote RG Research Group RG Ring Ground RGM Resource Group Manager (Sun Cluster) RGW Residential Gateway RH Request/Response Header RHC Regional Holding Company RI Ring In (Token Ring MAU) RI Ring Indicator (EIA-232-E) RI Route Index RIB Remote Insight Board RIBCL Remote Insight Board Command Language RIF Routing Information Field (Source Routing) RII Routing Information Indicator (Source Routing) RILOE Remote Insight Lights-Out Edition (HP) RIM Request Initializaiton Mode (HDLC) RIP Routing Information Protocol RIP Routing Information Protocol (IETF) RIPE Réseau IP Européen RISC Reduced Instruction Set Computer RISC Reduced Instruction Set Computer/Computing RJE Remote Job Entry RLCI Receive Line Clock Input RLDI Receive Line Data Input RLM Redundant Link Management RLSD Received Line Signal Detect (EIA-232-E) RM Resource Management RMAN Recovery Manager (Database) RMATS Remote Maintenance And Testing System RMDR Remainder RMON Remote Monitoring RMS Root Mean Square RN Reference Noise RNC Radio Network Controller (UMTS) RNR Receiver Not Ready (HDLC) RO Ring Out (Token Ring MAU) ROCP Residence Optional Calling Plan ROH Receiver Off Hook ROI Return On Investment ROM Read Only Memory ROMP Remote Operations Microprocessor ROR Rate of Return ROS Remote Operations Service ROSE Remote Operation Service Element (Application Layer) ROTL Remote Office Test Line ROUTREQ Routing Request ROW Right Of Way RP Radio Part RP Route Processor (Cisco) RPC Remote Procedure Call RPCU Radio Port Control Unit RPE-LTP Regular Pulse Excitation-Long Term Prediction (GSM) RPM Resource Prioritization Manager RPOA Recognized Private Operating Agency RPR Resilient Packet Ring RPS Ring Parameter Server RR Receiver Ready (HDLC) RRJ Registration Reject (RAS) RRM Radio Resource Management RRQ Registration Request (RAS) RRQ Return Request RRUD Residence Resale Usage Discounts RS-232C Recommended Standard-232C serial communications standard RS1 Radiofone Services, LLC RSA Rivest, Shamir and Adleman (encryption) RSA Rural Serving Area RSA Rural Statistical Area RSAP Resale Service Area Plan RSCS Remote Time Spooling Communications Subsystem RSCV Route Selection Control Vector RSL Radio Signaling Link RSL Received Signal Level RSM Remote Server Management RSM Remote Switching Module RSM Remote Switching Module (telephony) RSP Repair Service Bureau RSP Route/Switch Processor (Cisco) RSS Remote Switching (Sub)System RSS Remote Switching Sites RSS Remote Switching System RSU Remote Switching Unit RSUP Reliable SAP Update Protocol (Cisco) RSVP Resource Reservation Protocol RSX Real-Time Resource Sharing Executive RSZI Regional Subscription Zone Identity RT Remote Terminal RT Rotation Time RT Routing Type RTA Remote Trunk Arrangement RTA Rural Trading Area RTAD Remote Test Access Data RTB Retransmission Buffer RTC Run Time Control RTCP Real-Time Transport Control Protocol RTF Rich Text Format RTMP Routing Table Maintenance Protocol (AppleTalk) RTP Real-Time Transport Portocol RTP Real-Time Transport Protocol RTP Realtime Transport Protocol RTP Routing Update Protocol (VINES) RTR Retransmission indicator RTS Referral Tracking System RTS Request To Send (EIA-232-E) RTSE Remote Transfer Service Element (Application Layer) RTSP Real-time Streaming Protocol RTU Remote test Unit RU Request/Response Unit RVI Reverse Interrupt (BISYNC) RW Receiver Window RX Receive RZ Return to Zero S&E Service & Equipment S< Speech and Language Technology S-CDMA Synchronous CDMA S-PCN Satellite Personal Communication Networks S/N Signal to Noise Ratio S7AP SS7 Application Part S Signal splitter SA/SP Smart Access Shopping Protocol SA Service Author SA Source Address SA Special Access SA Subarea SAA Service Adaptive Access SAA Systems Application Architecture (IBM) SAAL Signaling ATM Adaptation Layer (ATM) SABM Set Asynchronous Balanced Mode (HDLC) SABME Set Asynchronous Balanced Mode Extended (HDLC) SAC Satellite Access Center SAC Service Access Codes SAC Single Attachment Concentrator (FDDI) SAC Special Access SACCH Slow ACCH (GSM) SAD Service Address Directory SAG Street Address Guide SAI Serving Area Interface SAM Service Access Multiplexer SAM Subscription and Account Management (Sicap) SAM System Administration Manager SAM System Adminitration Manager SAMI SAM Interface SAN Storage Area Network SANC Signaling Area Network Code SAP Service Access Point SAP Service Advertising Protocol (NetWare) SAP Special Access POTS service SAPI Service Access Point Identifier (LAPD) SAR-PDU Segmentation and Reassembly PDU SAR Segmentation and Reassembly SAR Segmentation and Reassembly (ATM) SAR Specific Absorption Rate SARM Set Asynchronous Response Mode (HDLC) SAS Serial Attached SCSI SAS Single Attachment Station SAS Single Attachment Station (FDDI) SASE Specific Applications Service Element (subset of CASE, Application Layer) SATA Serial ATA SATD Street Address Telephone Directory SB Signal Battery SB Summary Billing SB Synchronisation Burst SBI Subscriber Browser Interface SBI Synchronous Backplane Interface SBS Satellite Business Systems SBX Small Business Exchange SC-FDE Single Carrier Frequency Domain Equalization SC Service Creator SCA Selective Call Acceptance SCA Subsidiary Carrier Authorization SCA System Communication Architecture SCAI Switch-to-Computer Application Interface SCAI Switch-to-Computer Application(s) Interface SCC Sattelite Communications Control SCC Special Common Carrier SCC Switching Control Center SCCP Signaling Connection Control Part SCCP Signaling Connection Control Point (SS7) SCCS Switching Control Center System SCE Service Creation Environment SCEF Service Creation Environment Function SCF Service Control Function SCH Synchronisation Channel SCO Santa Cruz Operation SCP Service Control Point SCP Service Control Point (SS7) SCP Session Control Protocol SCPC Single Channel Per Carrier SCPS Service Control Point Simulator SCR Sustained Cell Rate (ATM) SCSA Signal Computing System Architecture SCSI Small Computer Systems Interface SCTE Serial Clock Transmit External (EIA-232-E) SCTP Simple Control Transmission Protocol SD Speaker Dependent SD Starting Delimiter (LAN) SDCCH Standalone Dedicated Control Channel SDCU Synchronous Data Channel Unit SDF Service Data Function SDH Synchronous Digital Hierarchy SDH Synchronous Digital Hierarchy (ITU-T,SONET) SDK Software Development Kit SDL Specificatil and Description Language SDLC Synchronous Data Link Control SDLC Synchronous Data Link Control (IBM) SDLLC SDLC Logical Link Control (Cisco) SDM Space-Division Multiplexing SDM Substrate Data Mux SDMA Spatial Division Multiple Access SDN Software Defined Network SDN Software Defined Network Control Center SDP Service Data Point SDP Service Definition and Provisioning SDP Session Description Protocol SDR Speaker Dependent Recognition SDRAM Synchronous DRAM SDRAM Synchronous Dynamic Random Access Memory SDS Scientific Data Systems SDS Short Data Service SDS Switched Digital Services SDSAF Switched Digital Service Applications Forum SDSL Symmetric Digital Subscriber Line SDSU SMDS Data Service Unit SDT SDL Design Tool SDTV Standard Definition (digital) Television SDU Service Data Unit SE Status Enquiry (FR) SEAL Simple and Efficient Adaptation Layer SECAM Sequential Coleur Avec Memoire SECAM Sequential Coleur Avec Memoire (Sequential Color with Memory) Secure Internet Roaming SEE Service Execution Environment SEFL Single Ended Fault Locating SEL Selector Field SEP Service Execution Platform SEP Signaling End Point SES Severe Errored Seconds SET Secure Electronic Transaction SF Service Function SF Signal Frequency SF Single Frequency SF Status Field SF Super Frame SF Superframe Format SFCDR Standalone Fast CDR Handler (Sicap) SFH Slow Frequency Hopping SFS Start of Frame Sequence (LAN) SG Signal Ground SG Signaling Gateway SG Study Group (ITU-T) SGCP Simple Gateway Control Protocol SGML Standard Generalized Markup Language SGML Standard Generic Markup Language SGMP Simple Gateway Management Protocol (IETF) SGRAM Synchronous Graphics RAM SGSN Service GPRS Support Node SGSN Serving GPRS Support Node SH SAR Sublayer Header SHARP Self-Healing Alternate Route Protection SHF Super High Frequency SHNS Self-Healing Network Service SHR Self-Healing Ring SI Service Indicator SI Service Information octet SI Single Instance SI Speaker Independent SIB Service Independent Buiding Block SIB Status Indication B (busy) SICDR Speaker Independent Connected Digit Recognition SID Silence Descriptor (GSM) SID System ID number SID System Identification SIDES Siemens ISDN Software Development and Evaluation System SIE Status Indication E (emergency alignment) SIF Signaling Information Field SIF Signalling Information Field SIG SIGnaling Transport SIG SMDS Interest Group SIG Special Interest Group SIGS Signaling Strobe SIGTRAN SIGnaling TRANsport SILS Standard for Interoperable LAN Security (IEEE 802.10) SIM Set Initialization Mode (HDLC) SIM Subscriber Identity Module SIM Subscriber Identity Module (GSM) SIM Subscriber Information Module SIMD Single Instruction stream, Multiple Data stream SIMM Single Inline Memory Module SIN Status Indication N (normal alignment) SINAD Signal-to-Noise Plus Distortion (ratio) SIO Scientific and Industrial Organizations (ITU-T) SIO Service Information Octet SIO Signaling Information Octet SIO Status Indication O (out of alignment) SIP Serial Interface Processor (Cisco) SIP Session Initiation Protocol SIP SMDS Inteface Protocol SIP SMDS Interface Protocol (Cisco) SIPB Siemens ISDN PC User Board SIR Speaker Independent Recognition SIR Sustained Information Rate (SMDS) SIT Special Identification Tone(s) SIT System Integration Testing SITA Society of International Aeronautical Telecommunications SIU Signaling Interface Unit SIV Speaker Identity Verification SJF Shortest Job First SK Service Key SL Service Layer SLA Service Level Agreement SLC Signaling Link Code SLC Subscriber Line Charge SLC Subscriber Loop Carrier SLDRAM SyncLink DRAM SLEE Service Logic Execution Environment SLEE Service Logic Execution Environment (HP) SLIC Subscriber Line Interface Card SLIP Serial Line Interface Protocol (IETF) SLIP Serial Line Internet Protocol SLM Single Longitudinal Mode SLP Service Logic Program SLP Service Logic Program (HP) SLP Single-Link Procedures (X.25) SLPI Service Logic Program Instance SLR Source Local Reference SLS Signaling Link Selection SLS Single Link Set SLS Spoken Language Systems SLU Secondary Logical Unit SM Service Manager SM Single Mode SM Switching Module (AT&T 5ESS) SMAF Service Management Access Function SMAF Service Management Agents Function SMAP System Management Application Part SMASE Systems Management Application Service Element SMATV Satellite Master Antenna TV SMB Server Message Block SMC Switch Maintenance Center SMD-PP Short Message Delivery - Point to Point SMDF Subscriber Maintenance Distributing Frame SMDI Simple Message Desk Interface SMDR Station Message Detail Recording SMDS Switched Multimegabit Data Service SMDS Switched Multimegabit Data Service (Bellcore) SME Short Message Entity SME Subject Matter Expert SMF Single-Mode Fiber SMG Special Mobile Group (ETSI) SMI Structure of Management Information SMI Structured Management of Information (OAM) SMIL Synchronized Multimedia Integration Language SML Service Management Layer SMP Service Management Point/Platform SMP Simple Management Protocol SMP Switching Module Processor SMP Symmetric MultiProcessing SMPP Short Message Peer to Peer SMPP Short Message Peer to Peer Protocol (GSM - UMTS) SMR Special Mobile Radio SMR Specialised Mobile Radio SMS-C Short Message Service Centre SMS-MO SMS Mobile Originated SMS-MT SMS Mobile Terminated SMS-PP SMS Point to Point SMS Service Management System SMS Short Message Service (GSM - UMTS) SMS Speech Mail System SMSA Standard Metropolitan Statistical Area SMSC Short Message Service Centre (GSM - UMTS) SMSCB Short Message Service Cell Broadcast SMSCB SMS Cell Broadcast SMTP Simple Mail Transfer Protocol (IETF) SMTS Senior Member of Technical Staff SN&M Service Negotiation and Management SN Sequence Number (ATM, DQDB, SMDS) SN Serial Number SN Service Node SN Subscriber Number SN Switching Network SNA Systems Network Architecture SNA Systems Network Architecture (IBM) SNADS SNA Distributed Services SNAP Subnetwork Access Protocol (IEEE 802) SND Send SNDCP Sub-network Dependent convergence Protocol SNDR Sender SNET Southern New England Telephone Company SNI Subscriber Network Interface (SMDS) SNMP Simple Network Management Protocol SNMP Simple Network Management Protocol (IETF) SNMP Simple Network Management/Monitoring Protocol SNMPIF SNMP Interface Module (SZ) SNMPv2 SNMP version 2 (IETF) SNP Sequence Number Protection SNR Signal to Noise Ratio SNR Single Number Reach SNRM Set Normal Response Mode (HDLC) SNRME Set Normal Response Mode Extended (HDLC) SO Service Order SO Serving Office SO Switch Over (HA) SOA Service Order Administration SOAC Service Order Analysis & Control SOAP Simple Object Access Protocol (Protocol) SOFE Service Order Front End system SOH Section Overhead (SONET) SOH Start Of Header SOH Start of Header (BISYNC) SOHO Small Office - Home Office SOHO Small Office/Home Office SOJ Small Outline J-Lead SONET Synchronous Operating NETwork SONET Synchronous Operating/Optical NETwork SONET Synchronous Optical Network (BISYNC) SORD Service Order Retrieval and Distribution system SP SAR Sublayer Payload SP Service Provider SP Signaling Point (ANSI) SP Switch Processor (Cisco) SP Switching Point SPA Security Posture Assessment (Cisco) SPA Specific Poll Address (SS7) SPAG Standards Promotion and Application Group (BISYNC) SPAN Space Physics Analysis Network SPAN Switched Port Analyzer (Cisco) SPARC Scalable Performance Architecture SPC Signaling Point Code (SS7) SPC Statistical Process Control SPC Stored Program Control SPC Switched Permanent Circuits SPCL Spectrum Cellular SPCR Serial Port Control Register SPCS Stored Program Control System SPCS Stored Program Controlled Switch SPD Serial Presence Detect SPDU Session Protocol Data Unit SPE Synchronous Payload Envelope (SONET) SPF Shortest Path First SPI Software Plug In SPID Service Profile Identifier (ISDN) SPIN Service Provider Identification Number SPLNP Service Provider Local Number Portability SPM Space Switch Module SPMP Service Provisioning Measurement Plan SPN Service Provider Number SPOC Single Point of Contact SPOF Single Point of Failure SPP Sequenced Packet Protocol (NetWare) SPRM Supplementary Performance Report Message SPT Speech Processing and Telephony (telephone front-end) SPTN Single Protocol Transport Network SPX Sequenced Packet Exchange (NetWare) SQ Signal Quality Detector (EIA-232-E) SQAM Staggered Quadrature Amplitude Modulation SQD Signal Quality Detector SQL Structured Query Language SQL Structured Query Language (Database) SQPSK Staggered Quadrature Phase Shift Keying SQR Signal to Quantizing noise Ratio SR-TB Source Routing-Transparent Bridging (IEEE) SR Selective Routing SR Service Request SR Source Routing (IBM) SRAM Static RAM SRD Secondary Received Data (EIA-232-E) SRDM Sub Rate Data Multiplexer SRE Sicap Rating Engine SREJ Selective Reject (HDLC) SRES Signed Response (GSM) SRF Specialized Resource Function SRF Specifically Routed Frames (Token Ring SR) SRI SIP Relay Interface (SMDS) SRL Singing Return Loss SRM Signaling Route Management SRP Spatial Reuse Protocol SRP Specialized Resource Platform SRP Specialized Resource Point SRT Source Routing Transparent SRTS Synchronous Residual Time Stamp SS6 Signaling System 6 SS7 Signaling System #7 SS7 Signaling System 7 SS Spread Spectrum SS Supervisory Center SS Suplementary Services SS Supplementary Service Support SS Switching System (SMDS) SSA Station Select Address (BISYNC) SSAP Session Service Access Point (LLC) SSB Signal Side Band SSBSC Single Sideband Suppressed Carrier SSCP Service Switching and Control Point SSCP System Service Control Point SSCP System Service(s) Control Point SSCS Service Specific Convergence Sublayer SSE Silicon Switching Engine (Cisco) SSF Service Switching Function SSF Subservice Field (SS7) SSH Secure SHell SSI Single System Imaging SSL Secure Socket Layer SSM Single Segment Message (DQDB, SMDS) SSML Speech Synthesis Markup Language SSN SubSystem Number SSN Switched Services Network SSP SCCP Subsystem Prohibited SSP Service Switching Point (SS7) SSP Siemens Switching Processor SSP Silicon Switch Processor (Cisco) SSPE Service Switching Point Emulator SSS SMDS Switching System SSS Subscriber Switching Subsystem SST Synchronous Service Transport SSTDMA Spacecraft Switched Time Division Multiple Access ST SAR Sublayer Trailer ST Segment Type (DQDB, SMDS) ST Signaling Terminal ST STop (end of pulsing signal) ST Subscribers Terminal STA Spanning Tree Algorithm (LAN) STACK Start Acknowledgement STCR Syncron Transfer Control Register STD Secondary Transmitted Data (EIA-232) STDM Statistical Time Division Multiplexer STE Section Terminating Equipment (SONET) STE Signaling Terminal Equipment(V.75) STE Spanning-Tree Explorer (LAN) STK SIM Tool Kit (GSM - UMTS) STK SIM ToolKit STM SONET Terminal Multiplexer STM Synchronous Transfer Mode STM Synchronous Transport Module (SDH) STP Service Traffic Position STP Shielded Twisted Pair (Physical Layer) STP Signaling Transfer Point (SS7) STP Spanning Tree Protocol (Data Link, Bridges) STP Strategic Technical Project STS-1 Synchronous Transport Signal (level)-1 STS Synchronous Transport Signal (SONET) STUN Serial Tunnel (Cisco) STX Start of TeXt (BISYNC) SU Signal(ing) Unit SUA SCCP User Adaptation SUERM Signal Unit Error Rate monitor (SS7) SUS Suspend (SS7) SVC Signaling Virtual Channel (ATM) SVC Switched Virtual Call SVC Switched Virtual Circuit SVC Switched Virtual Circuit (Packet Switching) SVC Switched Virtual Connection SVD Simultaneous Voice Data SVGA Super Video Graphics Array SVI Subvector Identifier SVS Select Vertical Spacing (Teletex) SVV Subvector Value SW Seeker Wireless SWAP Shared Wireless Access Protocol SWC Serving Wire Center SWC Switching Wire Center SWF-DS1 Switched Fractional DS1 SWF Switched Fractional SWFC Sliding-Window Flow Control SXS Step-by-Step (Switching) SXS Step-by-step Switch SYN Synchronization SYNCH SYNCHronous SYNTRAN SYNchronous TRANsmission System SZ Seeker Zone T-1 DS-1 digital system T Tip TA Terminal Adapter TA Terminal Adapter (ISDN) TA Timing Advance TA Timing Advance (GSM - UMTS) TAC Cisco Technical Assistance Center TAC Terminal Access Circuit TACACS+ Terminal Access Controller Access Control System Plus TACACS+ Terminal Access Controller Access Control System Plus (Cisco) TACD Telephone Area Code Directory TACS Total Access Communications System TAF Terminal Adaption Function (GSM) TAG Technical Advisory Group (IEEE 802) TAG Trunk Assignment Group TALI Transport Adapter Layer Interface TAM Timer Active Monitor TAN Technician Access Network TAO Telephony Access Object TAP Test Access Path TAP Transferred Account Procedure TAPI (Microsoft's) Telephone/Telephony Application Programming Interface TAPI Telephone/Telephony API (Microsoft) TAPI Telephony API TASI Time Assigned Speech Interpolation TAT Terminating Attempt Trigger TAT TransATlantic TAU Test Access Unit TAU Time Assignment Unit TAXI Transparent Asynchronous Transmitter/Receiver Interface (Physical Layer) TB Transparent Bridging TBD To Be Determined TBE Toll Billing Exception TBR Technical Basis for Regulation TC Telecommunications Closet TC Terminating Channel TC Textual Convention (GSM - UMTS) TC Transaction Capabilities TC Transmission Control TC Transmission Convergence TC Transmitted Signal Element Timing (DCE Source, EIA-232) TC Transport Connection TCA Threshold Crossing Alert TCAM Telecommunications Access Method (SNA) TCAM Telecommunications Communication Access Method TCAP Transaction Capabilities Application Part TCAP Transaction Capabilities Application Part (SS7) TCH Traffic Channel (GSM) TCI Telephone Company Identification TCIF Telecommunications Industry Forum Tcl Tool Command Language TCM Tandem Connection Maintenance TCM Time Compression Multiplexing TCM Trellis Coding Modulation TCN Topology Change Notification TCP/IP Transmission Control Protocol/Internet Protocol TCP Transfer Call Period TCP Transmission Control Protocol (IETF) TCP Transport Control Protocol TCU Telecommunications Control Unit (SNA) TCU Trunk Coupling Unit TD-CDMA Time Division CDMA TD-SCDMA Time Division-Synchronous CDMA TD Transmit Data TD Transmitted Data (EIA-232-E) TDC Terrestial Data Circuit TDCC Transportation Data Coordination Committee TDD Time Division Duplex(ing) TDI Tie Down Information TDM Technical Development Manager TDM Time Division Multiplexing TDMA Time Division Multiple Access TDMS Time Division Multiplexing System TDOA Time Difference Of Arrival TDP Trigger Detection Point TDR Time Domain Reflectometer TDX Time Delay to X TDY TIme Delay to Y TE1 Terminal Equipment type 1 (ISDN capable) TE2 Terminal Equipment type 2 (non-ISDN) TE Terminal Equipment (ISDN) TEI Terminal Endpoint Identifier (LAPD) TELNET Terminal emulation protocol & application TELRIC Total Element Long-Run Incremental Cost TEMPEST Transient ElectroMagnetic Pulse Emanation STandard TETRA Terrestrial Trunked Radio TFN Toll Free Number TFO Tandem Free Operation TFS Toll Free Service TFT Thin Film Transistor TFTP Trivial File Transfer Protocol TFTS Terrestrial Flight Telephone System TG Technical Group TG Trunk Group TGW Trunking GateWay TH Transmission Header THL Trans-Hybrid Loss THT Token Holding Timer THT Token Holding Timer (FDDI, Token Ring) TI Transaction Identifier TIA Telecommunications Industry Advisory TIA Telecommunications Industry Association TIC Telephony Interface Control TIE Time Interval Error TIF Transaction Interface Module (SZ) TIFF Tagged-Image File Format TIMS Transmission Impairement Measuring Set TIPHON Telecommunications and Internet Protocol Harmonisation over Networks TIRKS Trunk Integrated Records Keeping System TJ Times Journal Publishing Company TL1 Transaction Language One TLAP TokenTalk Link Access Protocol (Apple) TLB Translation Lookaside Buffer TLD Transmission Level Point TLH Transport Layer Header TLP Transmission Level Point TLPU Telecommunications Line Protector Unit TLS Transparent LAN Service TLV Tag Length Value TLWS Trunk and Line Work Station TM Terminal Multiplexer TMA Trunk Module Analog TMC Telecom Media Card (HP) TMC Telecommunication Media Card TMC Time slot Management Channel TMD Trunk Module Digital TMGB Telecommunications Main Grounding Busbar TMN Telecommunication(s) Management Network TMRA Recommended Ambient Operating Temperature TMS Time-Multiplexed Switch TMS Transport Management System TMSI Temporary Mobile Subscriber Identity TMSI Temporary Mobile Subscriber Identity (GSM - UMTS) TN Telephone Number TN Time slot Number TN Transit Node TNA Telephone Number Assignment TNS Transit Network Selection TOA Time Of Arrival TOA Type of Address (X.25) TOD Time Of Day TOH Transport Overhead (SONET) TOM Telecom Operations Map TOP Technical and Office Protocol (Boeing) TOPS Traffic Operator Position System TOS Testing Operation System ToS Type of Service TOS Type of Service (IP) TP-PMD Twisted Pair Physical Medium Dependent (FDDI) TP Toll Prefix TP Transaction Processing TP Transport Protocol (ISO) TP Twisted Pair TPAD Terminal Packet Assembler/Disassembler (BISYNC-BPAD) TPAU Twisted Pair Attachment Unit TPC Terminating Point Code TPCC TransPort Cross Connect TPDU Transport Protocol Data Unit TPG Terminating Point Group TPI Tip-Party Identification TPKT TCP Packets TQM Total Quality Management TR Technical Requirements TR Token Ring TR TransmitteR TRA Traffic Restart Allowed TRA Traffic Routing Administration TRAU Transcoder Rate Adapter Unit TRAU Transcoding Rate and Adaption Unit TRD Technical Requirements Document TRIP Token Ring Interface Processor (Cisco) TRS Telecommunications Relay Services TRSS Token Ring Subsystem TRT Token Rotation Time TRT Token Rotation Timer (FDDI, Token Ring) TRU Transmit/Receive Unit TRW Traffic Restart Waiting TRX Tandem Repeater Exchange TRX Transmitter/receiver (transceiver) TS Tandem Switching TS Terminal Server TS Time Slot TSAP Transport Service Access Point TSAPI (Novell's) Telephone/Telephony Application Programming Interface TSAPI Telephone/Telephony API (Novell) TSAT T-1 rate Small Aperture Terminal TSC Telecom Signaling Card (HP) TSC Telecommunication Signaling Card TSC Test System Controller TSC Training Sequence Code (GSM) TSDU Transport Service Data Unit TSG Technology Services Group TSGR Transport System Generic Requirements TSI Time Slot Interchange TSID Test Signal Identification TSM Terminal Server Manager TSM Time Switch Module TSM Timer Standby Monitor TSO Terminating Screening Office TSOP Thin Small Outline Package TSP Tandem Switch Provider TSPS Traffic Service Position System TSR Terabit Switch Router TSR Terminate and Stay Resident (program) TSR Terminate and Stay Resident programs TSS Telecommunication Standardization Sector (ITU-T) TSS Trunk and Signaling Subsystem TSS Trunk Servicing System TSSI Time Slot Sequence Integrity TST Tandem Switched Transport TST Time-Space-Time (Switching Process) TSTS Time-Space-Time-Space TSU Telecommunication Signaling Unit TT Text Telephone TT Touch Tone TT Transport Termination TTC Tandem Transit Charge TTD Temporary Text Delay (BISYNC) TTL Time To Live TTL Transistor-Transistor Logic TTP Timed Token Protocol (FDDI) TTP Trusted Third Party TTRT Target Token Rotation Time TTRT Target Token-Rotation Time (FDDI) TTS Text To Speech TTU Tandem T-1 Unit TU Trunk Unit TUI Telephone User Interface TUP Telephone User Part (SS7) TUR Traffic Usage Recorder TURN Toward Utility Rate Normalization TVRO Television Receive Only TVRO Television Receive OnlyBSS TW Transmitter Window TWA Two-Way Alternate (HDLC) TWS Two-Way Simultaneous (HDLC) TX Transmit UA Unbalanced Asynchronous (HDLC) UA Unnumbered Acknowledgement (HDLC) UA User Agent UAN User Access Node UARFCN UTRA Absolute Radio Channel Frequency Number (GSM - UMTS) UART Universal Asynchronous Receiver Transmitter UAS Unavailable Seconds UBR Unspecified Bit Rate (ATM) UCA Utility Communications Architecture UCAN Utility Consumers Action Network UCD Uniform Call Distribution UCD User Centered Design UCIC Unequipped Circuit Identification Code UCS Universal Communications Standards UDC Universal Digital Channel UDI Unrestricted Digital Information (ISDN) UDLC Univac Data Link Control UDLC Universal Digital Loop Carrier UDP User Datagram Protocol UDP User Datagram Protocol (IETF) UDT Unitdata UDTS Unitdata Service UE User Equipment (GSM - UMTS) UEL Universal Event Loader UHF Ultra High Frequency UI Unit Interval UI Unnumbered Information (HDLC) UI User Interface UID Unit Identification UISG Utility Industry Standards Group ULTRIX DEC's version of UNIX ULTS Universal Lifeline Telephone Service UM Unified Messaging UMB Upper Memory Block UMTS Universal Mobile Telecommunications System UMTS Universal Mobile Telecommunications System (GSM - UMTS) UN Unbalanced Normal UNC Universal Naming Convention UNI User Network Interface UNI User-Network Interface (ATM, FR) UNICODE UNIversal trunk-out-of-service Code UNMA Unified Network Management Architecture UP Unumbered Poll UPA User Part Available UPC Usage Parameter Control UPN Universal Personal Number UPS Uninterruptible Power System/Supply UPS United Parcel Service UPT Universal Personal Telecommunications UPT User Part Test UPU User Part Unavailable URI Universal Resource Identifier URJ Unregistration Reject (RAS) URL Uniform Resource Locator URL Uniform/Universal Resource Locator URN Uniform Resource Name URQ Unregistration Request (RAS) USAA United Services Automobile Association USART Universal Synchronous Asynchronous Receiver Transmitter USAT Ultra Small Aperture Terminal USB Universal Serial Bus USI User System Interface USIM UMTS SIM (UMTS) USIM Universal Subscriber Identity Module (3G) USO Universal Service Obligation USO Universal Service Order USOC Universal Service Offering/Order Code USOC Universal Service Order(ing) Code USP Usage Sensitive Pricing USR User-to-User Information (SS7) USS Unstructured Suplementary Services (SS) USSD Unstructured Supplementary Service Data (GSM - UMTS) USTA United States Telecommunications Association USTK UMTS STK (UMTS) USU USSD Service Utility UTAM Unlicensed PCS Ad Hoc Committee for 2-GHz Microwave UTC Coordinated Universal Time UTC Unable to Comply Ack (EOC) UTC Unacknowledged (Unnumbered) Information Transfer Control UTM Universal Transaction Monitor UTM Universal Transverse Mercator UTP Unshielded Twisted Pair UTP Unshielded Twisted Pair (Physical Layer) UTRA Universal Terrestrial Radio Access UTRAN Universal Terrestrial Radio Access Network UTS Unbundled Tandem Switching UUCP UNIX-UNIX Copy UUS User-to-User Signaling UVG Universal Voice-grade Channel Unit UWB Ultra Wide Band VAD Voice Activated Dialing VAD Voice Activity Detector (GSM) VAN Value Added Network VAN Value-Added Network VANC Voice Activated Network Control VANS Value Added Network Service VAP Value-Added Process VAPD Voice Activated Premier Dialing VAS Value-Added Services VAX Virtual Address Extension (DEC) VAXen Two or more VAXes VAZO Violating All-Zero Octet VBNS Very High-speed Backbone Network Service VBR-NRT Variable Bit Rate-Non-Real-Time (ATM) VBR-RT Variable Bit Rate-Real-Time (ATM) VBR Variable Bit Rate VBR Variable Bit Rate (ATM) VC Virtual Channel (ATM) VC Virtual Circuit (PSN) VC Virtual Connection VC Virtual Container (SDH) VCA Value Card Application VCC Virtual Channel Connection (ATM) VCI Virtual Channel Identifier VCI Virtual Circuit/Channel Identifier VCL Virtual Channel Link VCM Virtual Channel Memory VCR Video Cassette Recorder VCS Video Conferencing System VCS Virtual Circuit Switch VCS Voice Control Systems VDM Voice Data Mux VDSL Very high bit rate Digital Subscriber Line VDT Video Dial Tone VDU Visual Display Unit VE Virtual Environment VESP Video Enhanced Service Providers VF Voice Frequency VFG Virtual Facility Group VFL Voice Frequency Line VG Voice Grade VGA Video Graphics Array VHDCI Very High Density Cable Interconnect VHDSL Very High bit rate Digital Subscriber Line VHE Virtual Home Environment VHF Very High Frequency VI Vector Identifier VICS Voluntary Interindustry Communications Standards for EDI VIN Virtual Intelligent Network VINES Virtual Networking System (Banyan) VIP Versatile Interface Processor (Cisco) VIP VINES Internet Protocol VIP Virtual IP VL Vector Length VLAN Virtual Local Area Network VLBR Very Low Bit Rate VLF Very Low Frequency VLR Visiting Location Register VLR Visitor Location Register (GSM - UMTS) VLSI Very Large Scale Integration VM Virtual Machine VM Virtual Memory VME Versa Module Europe VMI Visual Message Indicator VMR Virtual Media Resource VMS Virtual Memory System VMS Virtual Memory System (DEC) VMWI Visual Message Waiting Indicator VN Virtual Network VNL Via Net Loss VNS Virtual Network System VoATM Voice Over ATM VoB Voice Over Broadband VOD Video On Demand VoDSL Voice Over DSL VOFDM Vector Orthogonal Frequency Division Multiplexing VoFR Voice Over Frame Relay VoiceXML Voice XML VoIP Voice Over Internet Protocol VOIP Voice Over Internet Protocols VoIP Voice over IP VON Voice On the 'Net VOP Voice Over Packet VP Vice President VP Virtual Path VPC Virtual Path Connection VPC Virtual Permanent Circuit VPC Virtual Private Circuit VPDN Virtual Private Dial-up Network VPI Virtual Path Identifier VPIM Voice Profile for Internet Mail VPN Virtual Private Network VPO Vantage Point Operations VPT Virtual Path Terminator VPX Virtual Path Cross-connect VQC Vector Quantizing Code VQC Voice Quantizing Code VQL Variable Quantizing Level VQL Vector Quantizing Level VQN Variable Quantizing Network VR Virtual Reality VR Voice Response VRAM Video RAM VRAM Video Random Access Memory VRC Vertical Redundancy Check VRML Virtual Reality Modeling Language VRU Voice Response Unit VSAM Virtual Storage Access Method VSAT Very Small Aperture Satellite VSAT Very Small Aperture Terminal VSAT Voice over Satellite VSB/AM Visual Side Band Aperture Modulation VSB Vestigial Sideband VSC Cisco's Virtual Switch Controller VSELP Vector Sum Excited Linear Prediction VSMSC Virtual SMSC VSP Video Service Provider VT Virtual Terminal (ISO) VT Virtual Tributary VTAM Virtual Telecommunications Access Method (SNA) VTAM Virtual Terminal Access Method VTE Virtual Terminal Environment VTP Virtual Terminal Protocol (ISO) VU Volume Unit VXML Voice Extensible Markup Language VXML Voice XML VxVM Veritas Volume Manager W-CDMA Wideband-CDMA W-DCS Wideband Digital Crossconnect System W3C World Wide Web Consortium WA Work Area WACK Wait Acknowledgement (BISYNC) WACS Wireless Access Communications System WAE WAP Application Environment WAIS Wide Area Information Server (IETF) WAIS Wide Area Information Service WAL WATS Access Line WAN-PHY WAN Physical Layer WAN Wide Area Network WAP Wireless Application Protocol WARC World Administrative Radio Conference WATS Wide Area Telecommunications Service WAW Wide Area Wireless WB/BB Wideband/Broadband WC Wire Center WCDMA Wideband CDMA WD Wideband Data/Digital WDCX Wideband and Broadband Digital Cross-connect WDM Wavelength Division Multiplexing WECA Wireless Ethernet Compatibility Alliance WEP Wired Equivalent Privacy WFA Work Force Administration WFA Work Force and Administration WFQ Weighted Fair Queuing WFW Windows For Workgroups (Microsoft) WGS Workgroup Systems WII Worldwide Information Infrastructure WILL Wireless Local Loop WIMP Windows, Icons, Mouse, and Pull-down menus (Xerox) WIN Wireless In-building Network WIN Wireless Intelligent Network WINForum Wireless In-building Network Forum WINS Warehouse Industry National Standards Guidelines WINTEL Windows Intel WISP WAP Internet Service Provider WLAN Wireless Local Area Network WLL Wireless Local Loop WM Wireline Modem WML Wireless Markup Language WOL Wake-on LAN WorkSCE Work Service Creation Environment WP White Pages WQAM Weighted Quadrature Amplitude Modulation WRAM Window RAM WRM Wavelength Router Manager (Cisco) WS Wireless Service WS Work Station WSC Wireless Subscriber Controller WSL Wireless Session Layer WSOP Working Service On Premises WSP Wholesale Service Provider WSP 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 (IETF) WYSIWYG What You See Is What You Get XA-FR Exchange Access Frame Relay XA-SMDS Exchange Access Switched Multi-megabit Data Service XA Exchange Access (SMDS) XAME eXchange Access Mapping Entity XAPIA X.400 API Association XBAR cross BAR switch XC Crossconnect XDF Extended Distance Feature XGA eXtended Graphics Array XI X Identification (frame) XI X.25 Interconnection XID Exchange Identification (HDLC) XML-RPC XML Remote Procedure Calls (Protocol) XML eXtensible Markup Language (Protocol) XMP X/Open Management Protocol XMS Extended Memory Specification XNS Xerox Network Systems XO Extended Office XPD Cross Polarization Discrimination XPD Cross-Polar Discrimination XPG X/Open Portability Guide XPI Cross-Polar Isolation XTP Express Transfer Protocol YP Yellow Pages ZBTS Zero Byte Time Slot ZBTSI Zero Byte Time Slot Interchange ZCS Zero Code Suppression ZIP Zone Information Protocol (AppleTalk) ZIS Zone Information Socket ZIT Zone Information Table ZUM Zone Usage Measurement SMBZ - SaMBoZaur - test for propagation of define: