==Phrack Magazine== Volume Four, Issue Forty-Three, File 22 of 27 {Acronyms Part II} D Data D Default supervision D Digits D Dispach D Hotel/motel equipment from trouble report (TSPS only) D-CTL D channel controller (IDEC) D/A Digital to analog D1PK DS-1 interface pack (SCM-10S NTI) D1PK DS-1 interface pack (SCM-10S MUX NTI) DA Digital data off-net extention INTER/TRA blocal 1-26 DA Directory assistance DAC Digital to analog converter DAC Dispatch Administration Center DACC Directort assistance call completion DACK Direct memory access acknowledge DACOM Data communictions corp. of korea (ROK) DACS Digital access cross-connect system DACS Digital accessed and cross-connected system DACS Directory assistance charging system DACTVTD Deactivated DAEDR Delimitation DAIS Distributed automatic intercept system DAML Digital added main line (pair gain) DAMT Direct access mechanize testing DAP Display administration process DAP Document application profile DARC Division alarm recording center DART Distribution area rehabilitation DARU Distributed automatic intercept system audio response unit DAS Data auxiliary set DAS Directory assistance system DAS Distributor and scanner DAS-WDT Distributor and scanner-watch dog timer DAS/C Directory assistance system/computer DASD Direct access storage device DASS2 Digital access signaling system 2 (BT) DAU Digital access unit DAV Data above voice DAY Delete an assembly DB DSSDS 1.5 mb/s access line INTER/TRA blocal 1-26 DB Decibel DBA Data base administrator DBAC Data base administration center DBAS Data base administration system DBCS Data bank control system DBL Data base load DBM Database manager DBMS Data base management system DBOS Data bank organization system DBS Duplex bus selector DBSS Data bank security system DC Device cinfirmation (C/I channel code) DC Dial code DC Direct current DCC Data collection computer DCC Data country code (ISO 7498) DCC Destination code cancellation DCC Destination code cancellation control DCC Digroup core controller DCCS Discontiguous shared segments DCD Data collection device DCE Data circuit terminal equipment DCE Data circuit-terminating equipment DCE Data communications equipment DCE Digital carrier equipment DCG Default cell group DCH D channel handler DCH D-channel handling bit DCH Discharge DCHOOS D-channel is out of service. DCL Data clock (i.e. IOM2) DCL Dec control language DCLU Digital carrier line uint DCLU Digital carrier line unit DCM Digital carrier module DCME Digital circuit multiplexing equipment DCMS Distributed call measurement system DCMU Digital concentrator measurement unit DCN List disconnected and changed numbers DCP D channel processor DCP Duplex central processor DCPR Detailed contuing property record (pics/dcpr) DCPSK Differential coherent phase-shift keying DCS Data communications subsystem DCS Digital crosconnect system DCS Digital cross-connect system DCS Direct current signaling DCSO Display compleated service order (lmos command) DCT Digital carrier trunk DCTB Dct bank DCTEXT DCT extended DCTN Defense commercial telecommunications network DCTS Dimension custom telephone service DCTUCOM Directly connected test unit common board DCTUPORT Directly connected test unit port circuit DCn Device control n DD Data downstream (i.e. IOM2) DD Delay dial DD Disk drives DD Due date DD Total switching control center (SCC) and field work time. DDC Direct department calling DDCMP Daily display conversation mode and printer DDD Direct distance dialing DDGT Digital data group terminal DDI Direct dialing-in (i.251 A) DDN Defense data network DDOV Digital data over voice DDS DDS loopback test (SARTS command) DDS Dataphone digital service DDS Digital data service DDS Digital data system DDS Digital data system (the network) dataphone digital DDS Digital dataphone service DDS Display the DS table DDX Digital data exchange DDX Distributed data exchange DEAC Deactivation (C/I channel code) DEACT Deactivate DEC Digital equipment corporation DECT Digital european cellular phone DEL Delete DEN Digital equipment number DERP Defective equipment replacement program DES Data encryption standard DES Destination DEST Destinations DET Detatch MSG. (i.451) DEV Deviation DEV Device DEW Distant early warning (line) DF Distributing frame DF Distribution frame DF HSSDS 1.5 mb/s hub to hub INTER/TRA blocal 1-26 DFC Disk file controller DFI Digital facility interface DFI Digital facility interface. DFI Digital family interface DFIH Digital facility interface circuit pair DFMS Digital facility management system DFTAC Distributing frame test access circuit DG HSSDS 1.5 mb/s hub to earth station INTER/TRA blocal 1-26 DGCT Diagnostic control table DGN Diagnose DGN Memory failure in CS/PS diagnostic program - 1AESS mem diag DH Digital service INTER/TRA blocal 1-26 DI Deactivation indication (C/I channel code) DI Direct-in dial INTER/TRA blocal 1-26 DI Unk division? DIA Document interchange architecture DIAG Diagnostic DIC Digital concentrator DIC Digital interface controller DID DI downstream DID Direct inward dialing DIF Digital frame interface DIF Digital interface DIF Digital interface frame DIFF Difference DILEP Digital line engineering program DIM Data in the middle DIP Dedicated inside plant COSMOS command DIP Dip creation option DIP Document interchange protocol (lower sublayer of OSI layer 6) DIP Dual in-line package DIR Direction DIR Directory DIR Standard dip report DIS Disconnect DIS Display DISA Direct inward system access DISABL Disable DISC Disconnect (LAP-D command) DISD Direct inward subscriber access DIST Distribute point board DIU Deactivate indication DIU Digital interface unit DIU Digroup interface unit (DACS) DIV (Ger) Digital exchange DIVF (Ger) Div for long distance service DIVO (Ger) Div for local service DJ Digit trunk INTER/TRA blocal 1-26 DK Data link INTER/TRA blocal 1-26 DL Dial DL Dictation line INTER/TRA blocal 1-26 DL1PE DLI 1 parity error DL5MDA Someone who collects each ISDN abbrevation crossing his way DLAB Divisor latch access bit DLC Data link control DLC Data link controller assignment for clusters DLC Digital loop carrier DLCI Data link connection identifier (i.440: SAPI+TEI) DLCU Digital line carrier unit DLE Data link escape (ascii control) DLI Data link interface DLI0I Data link 0 interrupt DLI1I Data link 1 interrupt DLISW DLI switch error DLL Dial long lines DLM Data link module DLN Direct link node DLNORSP Init response not received from data link. DLOPE Dual link interface (DLI) 0 parity error DLP Data level point DLS Digital line section DLS Digital link service DLTHA Display trouble history all (LMOS command) DLTU Digital line trunk unit DLTU Digital line/trunk unit DLU-PG Digital line unit-pair gain DLUC Digital line unit control DLYR Delayed readiness DM DMR DM Delta modulation DM Disconnected mode (LAP-D response) DMA Direct memory access DMB Digital multipoint bridge DMERT Duplex multiple environment real time DMI Digital multiplexed interface DML Data manipulation logic DMLHG DSN/AUTOVON MLHG DMQ Deferred maintenance queue DMS Data management system DMS Digital multiplex system (i.e. DMS 10, DMS 100) DMS Digital multiplexed system DMU Data manipulation unit DN Directory number DN Directory numbers DN Distribution network panel DN Down DN Mail distribution frame - COSMOS defult DNC Dynamic network controller DNH Directory Number Hunting DNHR Dynamic non hierarchical routing DNHR Dynamic nonhierarchical routing DNI Digital network interconnecting DNIC Data network identification code DNIC Data network identification code (ISO 7498) DNR Detaled number record DNR Dialed number recorder DNX Dynamic network X-connect DO Direct-out dial INTER/TRA blocal 1-26 DOC Dynamic overload control DOC Dynamic overload controls messages. DOCS Display operator console system DOD (USA) Dept. of defense DOJ Department of justice DOM Data on master group DOTS Digital office timing supply DOV Data over voice DP Demarcation point DP Dial pulse DP Digital data-2 4 kb/s INTER/TRA blocal 1-26 DPA Different premises address DPA Dispatch DPA Distributed power architecture DPAC Dedicated plant assignment card DPAC Dedicated plant assignment center DPC Destination point code (SSY) DPCM Differential PCM DPE Data path extender DPGS Digital pair gain systems DPIDB Direct PIDB DPIDB Directly connected peripheral interface data bus DPLL Digital phase locked loop DPN Dip purge number DPN-PH Data packet network-packet handler DPNSS Digital private network signaling system (BT) DPP Discounted payback period DPP Distributed processing peripheral DPR Dip report and removal DPSK Differential phase shift keying DPSK Differential phased-shift keying DPT Data parameter testing DPT Department name DPU Digital patch unit DQ Digital data-4 8 kb/s INTER/TRA blocal 1-26 DQR Design quota system report DQS Design quota system DR Data ready DR Data receive DR Deactivate request (C/I channel code) DR Deactivation request DR Digital data-9.6 kb/s INTER/TRA blocal 1-26 DRAM Digital record announcement machine DRAM Dynamic ram DRCS Dynamically redefinable character sets DRHR Division of revenue hourly DRMU Digital remote measurement unit DRTLRT Dial repe tie lindal repeatie t DRU DACS remote unit DS Data set DS Digital carrier span DS Digital signal DS Direct signal DS-0 Digital signal 0 (one channel at 64 kb/s) DS-0A Digital signal at a subrate level on DS-0 for one customer DS-0B Digital signals at a subrate level on DS-0 facility for one or more CU DS-1 Digital signal level one DS0 Digital signal zer0 DSBAM Double-sideband amplitude module DSBLD Disabled (default). DSC Digital cross-connection systems DSC Digital subscriber controller AM79C3A DSCT Digital service copper transport DSDC Direct service dial capability DSI Digital speech interpolation DSIG Direct signaling DSK Disk DSL Digital subscriber line DSL Digital suscriber line DSLG digital subscriber line group (DSLG) DSLINIT DSL initialization. DSM Digital switching module DSMX (Ger) Digital signal multiplexer DSN Defense switched network/automatic voice network DSN Digital signal (level) n DSNE Double shelf network equipment frame DSNOFC DSN/AUTOVON office totals DSNTG DSN/AUTOVON trunk group DSP Digital signal processing DSP Digital signal processing or digital signal processor DSP Digital signal processor DSP Domain specific part (ISO 7498) DSR Data set ready DSR Display results DSR Dynamic service register DSRTP Digital service remote test port DSS Data station selector DST Destination of order response DSU Data service unit DSU Data servicing unit DSU Digital service unit DSU2 Diditalservice unit DSX Digital cross-connect DSX Digital signal cross-connect DT DI-group terminal DT Data through (C/I channel code in test mode) DT Data transmit DT Detect dial tone DT Due time DT1 Data form class 1 DTAC Digital access connector DTAC Digital test access connector DTAC Digital test access connector (links SMAS and SLC-96) DTAM Document transfer access and manipulation DTAS Digital test access system DTAU Digital test access unit DTC Data test center DTC Di-group terminal controller DTC Digital telephone controller (ARCOFI + IBC + ICC) DTC Digital trunk controller DTE Data terminal equipment DTE Print current date DTF Dial tone first (pay phone) DTG Direct trunk group DTIF Digital transmission interface frame DTM Data test module DTM Digital trunk module DTMF Dual-tone multifrequency DTR Data terminal ready DTRK Digital Trunks DTRK Digital trunks (line and trunk) DTU Di-group terminal unit DTU Digital test unit DU Data upstream (i.e. IOM2) DU Deactivation request upstream (C/I channel code) DUIH Direct user interface handler DUP Data user part DUP Duplicate DUR Duration DUV Data under voice DVA Design verified and assigned DVX Digital voice exchange DW Digital data-56 kb/s INTER/TRA blocal 1-26 DX Duplex DY Digital service (under 1 mb/s) INTER/TRA blocal 1-26 DYRECT Sides dynamic real time communication tester (in sitest) E E (receive) signal lead (moreover Ear part of E&M) E Equipment direction E Remote trunk arrangement position subsystem (rta/pss) from troubl E&M Receive & transmit/ear & mouth signaling E-COM Electronic computer originated mail E1 Equipment system E800 Enhanced 800 Service E911 Enhanced 911 EA Equal access end office EA Expedited data acknowledgement (SS7: in SCCP) EA Extended adress EA Switched acess INTER/TRA blocal 1-26 EAAT Equal access alternative technologies EADAS Engineering and administration data acquisition system EADAS/NM EADAS/network management EAEO Equial access end office EAI Emergency action interface EAP Equal access plan EARN European academic research network EAS Extended announcement system EAS Extended area service EASD Equal access service date EB Enfia ii end office trunk INTER/TRA blocal 1-26 EBAC Equipmentc billing accuracy control EBCDIC Extended binary coded decimal interexchange code EBSP EBS prefix translations EBSP Enhanced business services prefix translations EC ESS entity and control group number EC Echo canceller EC Enfia ii tandem trunk INTER/TRA blocal 1-26 EC Environment code EC European community EC Exchange carriers ECAP Electronic customer access program ECC Enter cable change ECCS Economic c (hundred) call seconds ECD Equipment configuration database ECDMAN Equipment configuration database manager ECF Enhanced connectivity facility ECL Emitter coupled logic ECMA European computer manufactueres association ECPT Electronic coin public telephone ECR Exchange carrier relations ECS Electronic crosconnect system ECS Equipment class of service ED Enter date EDAC Electromechanical digital adapter circuit EDD Envelope delay distortion EDI Electronic data interchange EDP Electronic data processing EDSC Electronic directory customer counts (ISDN BRCS) EDSX Electronic digital signal x-connect EDZ Facility emergency assignment list EE Combined access INTER/TRA blocal 1-26 EE Initials of supervisor reviewing this ticket. EEC Electronic equipment cabinet EECT End-to-end call trace EEDP Expanded electronic tandem switching dialing plan EEE Electronic equipment enclosures EEHO Either end hop off EEI Equipment-to-equipment interface EEPROM Electrically erasable programmable read only memory EF Entrance facility-voice grade INTER/TRA blocal 1-26 EFCTS Electronic custom telephone service EFRAP Exchange feeder route analysis program EG Type #2 telegraph INTER/TRA blocal 1-26 EIA Electronic industries association EIS Expanded inband signaling EISS Economic impact study system EIU Extended interface unit EIn Error indication n (C/I channel code) EKTS Electonic key telephone service EKTS Electronic key telephone sets EL Emergency reporting line INTER/TRA blocal 1-26 ELA Entity load analysis ELDS Exchange line data service ELECL Electrical ELEMNTS Elements ELI Electrical line interface EM Emergency reporting center trunk INTER/TRA blocal 1-26 EM Encription module EM End of medium (ASCII control) EMC Electromagnetic capability EMC Electromagnetic compatibility EME Electromagnetic emission EMI Electromagnetic interference EML Expected measured loss EMM Expandable mos memory EMS Electromagnetic susceptibility EMS Expanded memory specification EMSCC Electromechanical switching control center EMV EMC (german) EN Entity EN Entity number EN Exchange network acess facility INTER/TRA blocal 1-26 ENABL Enable ENFIA Exchange network facility for interstate access ENHMT Enhancement ENQ Enquiry ENTDT Entered date and/or time EO End office EOC Embedded operation channel EOE Electronic order exchange EOM End of message EOS Extended operating system EOTT End office toll trunking EP Entrance facility-program grade INTER/TRA blocal 1-26 EP Expedited data (SS7: in SCCP) EPIC Extended PIC EPL Electronic switching system program language EPROM Erasable programmable read-only memory EPSCS Enhanced private switched communication service EQ Equalizer EQ Equipment only-(network only) assignment INTER/TRA blocal 1-26 EQPT Equipment ER Enhancement request ER Error register ER Exception report ERAR Error return address register ERC Error control (IOS) EREP Environmental recording editing and printing ERF Emergency restoration facility ERL Echo return loss ERP Effective radiated power ERPMP Exception report pumper ERR Error ERRS Errors ERTS Error rate test set ERTS Error rate test sets ERU Error return address update ES Extension service-voice grade INTER/TRA blocal 1-26 ESAC Electronic systems assistance center ESAP Emergency Stand-Alone prefix ESAP Emergency stand-alone prefix ESB Emergency service bureau ESC Enhanced speech circuit ESC Escape (ASCII control) ESC Three way calling USOC ESCC2 Extended high level serial communication controller ESCC8 Like ESCC2 ESD Electrostatic discharge ESD Extened super framing ESF Extended super frame ESF Speed calling USOC ESFF Extended superframe format ESL Emergency stand-alone ESL Essental service ESL Speed calling 8 code USOC ESM Call forwarding USOC ESM Economic study module ESMTC Electronic system maintance ESN Electronic serial number (Cell) ESN Electronic switched network ESN Emergency service number ESP Enhanced service procider ESP Enhanced service providers ESP Essential service protection ESP Print entire summary table ESS Electronic switching system ESSX Electronic switching systen exchange EST Established ESTAB Establish ESX Call waiting USOC ET Entrance facility-telegraph grade INTER/TRA blocal 1-26 ET Exchange termination ETAS Emergency technical assistance ETB End of transmission block ETC Estimated trunk ccs value ETF Electronic toll fraud ETL Equipment test list ETN Electronic tandem network ETRI Electronics and telecommunications research institute (ROK) ETS Electronic tandem switching ETS Electronic translation systems ETSACI Electronic tandem switching adminstration channel interface ETSSP ETS status panel ETX End of text EU End user EU Extension service-telegrasph grade INTER/TRA blocal 1-26 EUPOT End user-point of termination EV Enhanced emergency reporting trunk INTER/TRA blocal 1-26 EV Expected value EVB Busy call forward USOC EVC Bust call forward extended USOC EVD Delayed call forward USOC EVD Delayed call forwarding EVST (Ger) End exchange EW Off network MTS/WATS equivalent service INTER/TRA blocal 1-26 EWSD (Ger) Electronic dialing system (digital) EX Exercise EXD ECS crossloading option EXD Extra digit EXD Extra digit (MDII) EXP Extra pulse EXP Extra pulse (MDII) EXT Extension EXTC Expenditure type code F Facility direction F Fault (indicator) F Office or base unit from trouble report. F1 Facility system FA Frame aligner FA Fuse alarm FAA Facility accepted (SS7 in ISUP) FAC Facility FAC Facility Assiment Center FACD Facility changed msg. FACS Facilities assignment and control system FADS Dorce administration FANALM Fan alarm FAP Facilities analysis plan FAR Facility request (SS7: in ISUP) FAR Federal acquisition regulation FAS Frame alignment signal FAST First application system test FAT File allocation table FAX Faximile FC Feature control FC Frame control FC From cable FC/EC Function code and environment code FCA Final closure abandon (MDII) FCAP Facility capacity FCC Federal communications commission FCC Forward command channel FCC Frame control center FCD Frame comtinuity date FCG False cross or ground FCS File control systemction FCS Frame check sequence FD Private line-data INTER/TRA blocal 1-26 FDD Frame due date FDDI Fiber distributed data interface (x3t9.5) FDI Feeder/distribution interfaces FDM Frequency division multiplex FDM Frequency-division multiplexing FDMA FDM access FDP Field development program FDT Frame due time FDX Full duplex FDY Set fiscal day for LAC FEA Custom calling feature/PIC FEA Customer feature FEAT Feature FEAT Features FEBE Far end block error (IOM2 monitor message) FEC Forward error correction FECC Front end communication computer FED Far end data FELP Far end loop process FEMF Foreign electro-motive force FEPS Facility and equipment planning system FEV Far end voice FF Check appropriate space where trouble is located FF Form feed FG Group-supergroup spectrum INTER/TRA blocal 1-26 FGA Feature group A FGB Feature group B FGC Feature group C FGD Feature group D FGE Feature group E FGK Feature group K (ISDN Q.931) FIB Forward indication bit (SS7) FID Field indentifiers FIFO First in FIFO First in first out (storage) FIL Filter FIN Facility information msg. FIOC Frame input/output controller FIP Facility interface processor FIPS Federal information processing standards FISU Fill in signal unit (SS7) FITL Fiber in the loop FJ Frame jump (C/I channel code) FKP False key pulse FKP False key pulse (MDII) FL Fault locate FL Fault location FLA Flag FLD Field FLEXCOM Fiber optic communication FLR Frame layout report FLT Flat FM Frequency modulation FM01 DCT alarm activated or retired - 1AESS FM02 Possible failure of entire bank not just frame - 1A FM03 Error rate of specified digroup - 1AESS FM04 Digroup out of frame more than indicated - 1AESS FM05 Operation or release of the loop terminal relay-1AESS FM06 Result of digroup circuit diagnostics -1AESS FM07 Carrier group alarm status of specific group - 1AESS FM08 Carrier group alarm count for digroup - 1AESS FM09 Hourly report of carrier group alarms - 1AESS FM10 Public switched digital capacity failure - 1AESS FM11 PUC counts of carrier group errors - 1AESS FMAC Facility maintance administration center FMAC Facility maintenance and control FMC Force management center FMM Finite message machine FN Feature number FN File name FNBE Far and near end block error (IOM2 monitor message) FNPA Foreign numbering plan area FOA First office application FOC Fiber optic communications FON Fiber optics network FOR Frame order report FORPOT Foreign potential. FOS Frame operations summary FOS-ALC Fiber optic systems maintance - Alcatel FOS-ROCK Fiber optic system maintance - Rockwell FOT Forward transfer (SS7: in ISUP) FP Functional protocol FPC Foundation peripheral controller FPC Frequency comparison pilots FPS Fast packet switching FR Fire dispatch INTER/TRA blocal 1-26 FR Fixed resistance FR Flat rate FRAC Frame aligner circuit FRC Forced request configuration FREQ Frequency FRJ Facility rejected msg. (SS7 in ISUP) FRMR Frame reject (LAP-D response) FRPS Field reliability performance studies FRQ Facility request message FRS Flexible route selection FS File separator FS/SYM Function Schematic/Symbol Numbers (1AESS Test access) FSA False start abandon FSA False start abandon on incoming trunk FSC Frame synchronization clock (i.e. IOM2) FSK Frequency shift keying FSN Forward sequence number FT Foreign exchange trunk INTER/TRA blocal 1-26 FT Frame time FTA Frame transfer analysis FTC Frame transfer completion FTE Frame transfer establishment FTG Final trunk group FTL Frame transfer lets FTP File transfer protocol FTR Frame transfer reprint FTS Federal telecommunications system FTW Frame transfer withdrawal FUNCS Functions FV Voice grade facility INTER/TRA blocal 1-26 FW Wideband channel INTER/TRA blocal 1-26 FWD Forward FWM Frame work management FWS Frame work station FX Foreign exchange FX Foreign exchange INTER/TRA blocal 1-26 FXO Foreign exchange circuit office direction FXS Foreign exchange circuit station direction G Spare box. use for special studies. GAP (Ec) group of analysis and provision (for ONP) GB Great britain GBS Group bridging service GC Group card GCE Gated Oscillator Error GCI General circuit interface (IOM/u(k0)-interface) GCON Generic conditions GCP Generate Control pulse GCR General configuration register GCS Group control system GDSUCOM Global DSU common GDSUCOM Global digital service unit common GDX Gated diode crosspoint GDXACC Gated diode crosspoint access GDXC Gated diode crosspoint compensator GDXCON Gated diode crosspoint control circuit GEISCO General electric information services company GFR General facility report GG Getails of reported trouble. GH Gain hit GHZ Gigahertz GID Group ID GKCCR Generated key collection and compression routine GLA Generate lists for assignment GND Ground GNS Gainslope GNS Gainslope test (SARTS command) GOC General order control (TIRKS) GOS Grade of service GP Group processor GPA Gas pressure alarm GPIB General purpose interface bus GPPC General purpose power controller GPS Global positioning system GR General requirments (BellCoRe) GRA GRS acknowledgement GRASP Generic access package GRD Ground fault. GRD Ground. GRID Line unit grid. GRP Group GRP MOD Group modulator GRS Circuit group reset (SS7: in ISUP) GS Ground start (on-hook normal) GS Group separator GSA General services administration GSAT General telephone and electronics satellite corporation GST Ground start signaling GSZ Group size GTC General telephone company GTE General telephone electronics GTEI Global tei GTS Gamma transfer service GTT Global title transmission GWY Gateway Ger German H Hold state (in EOC) H Hours H Trouble ticket number. subparagraph 5.6.4. H&D High and dry (trunk test) H- High- H-RAP Hardware reliability assurance program HAC Hands-free add-on circuit (for speakerphone) HBS Hunt group blocks of spares HC High capacity 1.544 mb/ps-service code for LATA access HC Hunt count HCDS High capacity digital service HCDS High-capacity digital services HCFE High-capacity front end HCSDS High-capacity satellite digital service HCTDS High-capacity terrestrial digital service HD High capacity 3.152 mb/ps-service code for LATA access HDB3 High-density bipolar 3 (cept PRI) HDFI HSM digital facilities interface HDLC High level DLC HDLC High-level data link control HDSL High bit-rate digital subscriber line HDTV High definition television (soon to be the new buzz word!!) HDW Hardware HDX Half duplex HE High capacity 6.312 mb/ps-service code for LATA access HEAP Home energy assistance program HEHO High end hop off HF High capacity 6.312-service code for LATA access HF Hunt-from telephone number HFCC High capacity facility control center HFR Hardwara failure rate HG High capacity 274.176 mb/s-service code for LATA access HGBAF Hardware group blocking acknowledgment failure HGR Hunt group report HGS Hunt group summary HGUAF Hardware group unblocking acknowledgment failure HH History header HH Record of repair activity. HI High HI High impedance (C/I channel code) HI Highway interrupt HIC Hybrid integrated circuit HIM Host interface module HIS Hunting ISH HK Hook HL IT Siemens semiconductors (hl) HLC Highest lead factor group count HLDG Holding HLLAPI High level language application program interface HLSC High-level service circuits HM1 Intercom plus USOC HMCL Host message class assignment HMP Intercom plus HNPA Home numbering plan area HNS Hospitality network service HOBIC Hotel billing information center HOBIS Hotel billing information system HOLD Call hold (i.253 b) HP Hewlett-packard HP Non-DDS digital data 2.4 kb/s INTER/TRA blocal 1-26 HPO High performance option HQ Non-DDS digital data 4.8 kb/s INTER/TRA blocal 1-26 HR Hour HR Non-DDS digital data 9.6 kb/s INTER/TRA blocal 1-26 HRS Hours prefix HS High capacity subrate-service code for LATA access HSCC High level serial communication controller sab82520 HSCX Extended hscc sab82525 HSM Host switching module HSSDS High-speed switched digital service HT Horizontal tabulator HT Hunt-to telephone number HTI Highway transfer interrupt HU High usage HU High-usage trunk HUNT Hunting HUTG High usage trunk group HW High and wet. HW High-and-wet HW Non-DDS digital data 56 kb/s INTER/TRA blocal 1-26 HW Pcm highway HZ Hertz I Cable and pair or associated equipment I Information (LAP-D command) I Installation I Invalid I&I Investment and inventory I&M Customer services installation and maintenance I&M Installation & maintenance I- Information (numbered i-frames) I/O Ineffective other I/O Input/output devices I/O Tnput/output I0 Feature removed I1 Added feature IA Immediate action IA Ineffective attempts IAA Ineffective attempt analysis. IAAN Immediatel action report IAC0 DLI 0 access error IAC1 DLI 1 access error IACS Intergrated access cross-connected system IAD Incomplete address detected (incoming) IAM Initial address msg. (SS7: in ISUP) IB Instruction buffer IBC ISDN burst transceiver circuit IBN Integrated business network IBROFC ISDN BRCS and Analog Office totals IC Incoming call (x.25) IC Independent carrier IC Installation centers IC Inter-LATA carrier IC Inter-exchange carrier IC Interexchange carriers IC/MC Installation and maintence centers ICA Incoming advance ICA Incoming advance (MDII) ICAN Individual circuit analysis ICAO International civil aviation organization ICC ISDN communications controller ICC Interstate commerce commission ICCU Inmate call control unit ICD Interactive call distribution ICL Intra-RSM communication link ICLID Individual calling line id ICM Integrated call management ICN Interconnecting network ICOM (taiwan) integrated communication ICOT Intercity and outstate trunk ICP Intercept ICPOT Interexchange carrier-point of termination ICSC Inter-LATA customer service center ICSC Interexchange carrier service center ICSC Interexchange customer service center ICUG International closed user groups ICUP Individual circuit usage and peg count ICUR Individual circuit usage recorder ID Idle control code IDA (gb) interated digital access (b64+b8+d8) IDC Information distribution companies IDCI Interim defined central office interface IDCU Integrated digital carrier unit IDCU Integrated digital carrier unit . IDCU Integrated digital carrier unit i.e. AT&T Series 5 RT FP 303G IDDD International direct distance dialing IDEC ISDN d-channel exchange controller IDF Intermediate distributing frame IDI Initial domain identifier (ISO 7498) IDLC Integrated digital loop carrier IDLC Intergrated digital loop carrier IDP Individual dialing plan IDPC Integrated data protocol controller IDS Internal directory system IDVC Integrated data/voice channel IEC ISDN echo cancellation circuit IEC Interexchange carrier IEC International electrotechnical comission IEC-P (old name of iec-q3) IEC-Q1 Iec for 2b1q peb2091 IEC-Q2 Iec-q specially for lt and NT1 (without microprocessor) IEC-Q3 Iec-q with parallel processor interface (i.e. for daml) IEC-T Iec for 4b3t peb2090 IEEE Institute of electrical and electronics engineers IEPC ISDN exchange power controller IF Intermediate frequency IFAC Integrated digital carrier unit facility IFRB International frecuency registration board IFRPS Intercity facility relief planning system IFS (switzerland) integrated telecom service IGS Idenitfy graphic subrepertoire (teletex) IIN Integrated information network IJR Input a jeopardy reason ILC ISDN link controller ILINE IDCU line counts. IM Input mux IM Interface module IMA Additional ineffective machine attempts IMAS Integrated mass announcement system IMC IOS mailbox control IMCAT Input message catalog IMCF Interoffice multiple call forwarding IMD Intermodulation distortion IMM Input message manual IMMU IOS memory management unit IMP Impedance IMP Impules per minute IMP Interpersonal messaging protocol (x.420: p2) IMS Interprocessor message switch IMT Inter-machine trunk IMTS Improved mobile telephone service IMU Input measured ccs usage data IN Intelligent network IN/1 Intelligent network/1 INA Intergrated network access INAP Intelligent network access point INC Incoming trunk groups INC International calling INC International carrier INC SEL Incoming selector INCAS-A Integrated network cost analysis - access INCAS-LT Integrated network cost analysis - local and toll INCAS-S Integrated network cost analysis - shared INCAS/E Integrated network cost analysis system INCAS/I Integrated network cost analysis system - embedded INCIS Integrated network cost information system INCP Incomplete IND Individual INF Information INF Information (SS7: in ISUP) INIT Allocation table initalization INL Inter node link INN Inter node network INQ Complete circuit inquiry INR Information request (SS7: in ISUP) INS (japan) information network system (b64+b16+d8) INT Interrupt (i.e. C/I channel code) INTCCTRL International code control (NTI) INTCHG Interexchange INTEGRIS Integrated results information service INTELSAT International telecommunications satellite consortium INTR Interrupt INW INWATS [code 258(8000-8299)] INWATS Inward wide area telecommunications system INWATS Inward wide area telephone service INWBLKD INWATS returned blocked INWBLKD Inward wide area telecommunications service (INWATS) returned blocked INWBUSY INWATS all lines busy INWCCBL INWATS code control blocked INWDBOV INWATS data base overload INWDBTO INWATS data base timeout INWDSBL INWATS direct signaling blocked INWNNPA INWATS nonpurchased NPA INWNNPA INWATS nonpurchased numbering plan area (NPA) INWNOXL INWATS returned no translation INWONPA INWATS invalid ONPA INWONPA INWATS invalid originating numbering plan area (ONPA) INWOVLD INWATS returned overload INWUNEQ INWATS returned unequipped INWVLIN INWATS vacant line number INWVNXX INWATS vacant NXX IO Inward operator IOAU Input/output access unit (univac) IOC Independent operating company IOC Input/output controler (shelf) IOC Integrated optical circuit IOC International overseas center IOCC International overseas completion center IOCP Input/output configuration process IOCS Input/output control system IODB IDCU on-demand B-channel IOI Secondary input/output interface pack(s) IOM ISDN-oriented modular (architecture and interfaces) IOM2 Extended iom IOMI Input/output microprocessor interface IOP Input-output processor IOP Input/output Processor IOP Input/output driver IOP Input/output processor IOS ISDN operational software IOS Input/output supervisor (IBM) IOS Inventory order system IOSF Input/output shelf assignment IOT Inter-office trunk IOT Interoffice test command (SARTS command) IOT Interoffice testing IOTC International originating toll center IP Information provider IP Inprogress IP Intermediate point IP Internet protocol IPABX ISDN pabx IPAC ISDN pc adapter circuit IPACS Interactive planning & control system IPAT ISDN primary access transceiver IPB Sipb IPBC IOM2 PBC (old name for EPIC) IPC Inter-process communication IPC Interprocess communication IPCS IOS process control system IPCS Installation product costing system IPCS Interactive problem control system IPIB Intelligent personal computer interface board IPIDB IDCU peripheral interface data bus IPL Initial program load IPL Interoffice private line signaling IPL Interoffice private line signaling test (SARTS command) IPLAN Integrated planning and analysis system IPLS InterLATA private line services IPM Impulse per minute IPM Impulses per minute IPM Interruptions per minute IPP IOS protocol part IPP Integrated planning process IPPC Interdepartmental project planning committee IPR Installation performance results system IPS Installation performance results IPS Integrated Provisioning System IPS Integrated provisions system IPX Integrated packet exchange IQS Instant request system IR Incoming register IRBR Integrated resource billing report system IRC International record carrier IRIS Industry relations information system IRLF Incoming register link frame IRM Information resource management IRMC Incoming register marker connector IRO Industry relations operations IROR Internal rate of return IRP Integrated revenue planning IRPC ISDN remote power control psb2120 IRR Internal rate of return system IRRS Interactive request and retrieval system IRS Industrial revenue summary IRT IDCU remote digital terminal IRU Integrated recovery utility (sperry) IS Interrupt set IS/SADQ Interstate special access demand quantification ISA Indicate status application ISAC-P ISDN subscriber access controller ISAC-S ISDN subscriber access controller ISAM Indexed sequential access method ISC Intelligent serial controller ISC International switching center ISC Planintercompany services coordination plan ISC/TE Information systems center for technical education ISCAR Information systems costs analysis reports ISCOM SWBT intercompany service coordination (ISC) order monitor ISCP Integrated service control point ISCP/MSAP ISCP/multi-service application platform ISCP/SPOCK ISCP/service provisioning and on-line creation tool kit software ISDN Integrated services digital network ISF Inquire on a single facility ISG Isolated system grounding ISH Complete circuit inquiry short ISI Industry support layout ISIS Interstate settlements information system ISLM Integrated services line module ISLU Integrated services line unit ISLUCC Integrated services line unit common controller ISLUCD Integrated services line unit common data ISLUHLSC Integrated services line unit high level service circuit ISLUMAN Integrated services line unit metallic access network ISLURG Integrated services line unit ringing generator ISM ISDN switching module ISM Interactive synchronous mode ISMP Industry specific measurement plan ISMS Integrated service management system ISMTL Information systems management training ISN Information systems network ISN Integrated systems network ISNET Interim solution network (Kansas city only) ISO Information systems organization ISO International organization for standardization ISOFC ISDN office totals ISOPDB Information systems organization planning data base ISOSS Intercompany service order switching system ISP Intermediate service part ISPBX Integrated systems PBX ISPC International signaling point code (SS7) ISPF Interactive system productivity facility ISPI ISDN packet interface ISRP Information systems rules panel ISS Integrated switching system ISS Issue ISSANRC Interstate special access non-recurring ISSC Interfunction special service coordination ISSCO Intertoll ISSN Integrated special services network ISSN Intergrated specal services network ISSS ISDN supporting system ISTA Interrupt status register ISUP ISDN user part ISUP ISDN user part (SS7: q.76x) ISUP Integrated services user part IT Inactivity test (SS7: in SCCP) IT Intertandem tie trunk INTER/TRA blocal 1-26 ITAC ISDN terminal adaptor circuit ITC Independent telephone company ITC Interdepartmental training center at dallas-texas for ITD Intertoll dial ITEA Interoffice trunks engineering and administration ITF Integrated test facility ITG Intergrated traffic generator ITIMS Integrated transportation information management system ITIMS/IE Itims/information expert ITM Cable pair item number ITNA Improves thrid number acceptance ITNO Item number ITS Institute of telecommunication science ITS Integrated test system ITS Interactive training system ITSE Incoming trunk service evaluation ITSO Incoming trunk service observation ITSTC Information technology steering committee (cen ITT Idle trunk test ITU International telecommunication union ITU International telecommunications union ITVSE Intermediary transport vendor service center ITW Instructional technology workshop IU Network/port interface unit IUP Installed user program (IBM) IVD Integrated voice data IVP Installation verification procedures IVP Installation verification program IVTS International video teleconferencing service IWF Interworking facility (gateway) IWU Interworking unit (gateway) IX Interactive executive IXC Or icinterexchange carrier IXM Interexchange mileage IZ Interzone