APPENDIX A Acronyms and Abbreviations* a atto (10-18) A ampere A angstrom AAR automatic alternate routing AARTS automatic audio remote test set AAS aeronautical advisory station AB asynchronous balanced (mode) (Link Layer OSI-RM) ABCA American, British, Canadian, Australian armies abs absolute ABS aeronautical broadcast station ABSBH average busy season busy hour ac alternating current AC absorption coefficient access charge access code ACA automatic circuit assurance ACC automatic callback calling ACCS associated common-channel signaling ACCUNET AT&T switched 56-kbps service ACD automatic call distributing automatic call distributor *Alphabetized letter by letter. Uppercase letters follow lowercase letters. All other symbols are ignored, including superscripts and subscripts. Numerals follow Z and Greek letters are at the very end. 1127 Appendix A 1128 ac-dc alternating-current direct-current (ringing) ACE automatic cross-connection equipment ACF/VTAM advanced communications facility (VT AM) ACK acknowledge character acknowledgement ACK/NAK acknowledgement/negative acknowledgement ACS airport control station asynchronous communications system ACSE association control service element ACTS advanced communications technology satellite ACU automatic calling unit AD addendum AID analog to digital A-D analog to digital ADAPT architectures design, analysis, and planning tool ADC analog-to-digital converter automatic digital control ADCCP Advanced Data Communications Control Procedure (ANSI) ADH automatic data handling ADP automatic data processing automatic data processor ADPCM adaptive differential pulse code modulation Association for Data Processing and Computer Management ADPE automatic data processing equipment ADPS automatic data processing system ADPSSO automatic data processing system security officer ADS automatic dependent surveillance ADSP AppleTalk Data Stream Protocol ADSU automatic dependent surveillance unit ADU automatic dialing unit ADX automatic data exchange AECS Aeronautical Emergency Communications System AECSP Aeronautical Emergency Communications System Plan AEF aircraft emergency frequency aeronautical emergency frequency AEQ automatic recovery quotient AES aeronautical Earth station AF audio frequency AFC area frequency coordinator automatic frequency control automatic frequency control Appendix A 1129 AFI address and fonnat identifier (ISO) AFNOR Association Fran~ais Nonnal (France standards body) Association Fran~aise des Nonnes (France Standards) AFP AppleTalk Filing Protocol AFRN Anned Forces Radio Network AFRS Anned Forces Radio Service AFS aeronautical fixed service aeronautical fixed station AG antenna gain AGC automatic gain control AGE aerospace ground equipment AGRS air-ground radiotelephone service AGWCS air-ground worldwide communications system AHF adaptive high frequency (radio) AI absorption index artificial intelligence AIG address indicator group address indicating group AIM amplitude intensity modulation AIN advanced intelligence network AIOD automatic identified outward dialing AIS automated infonnation system AISC application-specific integrated circuit AISS automated infonnation systems security AJ anti -jamming AL Application Layer ALAP AppleTalk Link Access Protocol ALBAM air-land battle assessment model ALC automatic level control automatic load control ALE automatic link establishment ALGOL Algorithmic Language ALMRBS airport land mobile radio base station ALMRS airport land mobile radio station ALOHA an experimental radio broadcast network ALU arithmetic and logic unit arithmetic and logical unit Nm amperes per meter AM amplitude modulated amplitude modulation amplitude modulator Appendix A 1130 angle modulation ante meridian AMA automatic message accounting AMC administrative management complex AME amplitude modulation equivalent automatic message exchange AMI alternate mark inversion alternate mark inversion (signal) AMLCD active matrix liquid crystal display AMlPMNSB amplitude modulation/phase modulation/vestigial sideband AMPS Advanced Mobile Phone Service automatic message processing system AMPSSO automated message processing system security officer AM(R)S aeronautical mobile (route) service AMS aeronautical mobile service aeronautical multicom service AMS(OR)S aeronautical mobile-satellite (off-route) service AMS(R)S aeronautical mobile-satellite (route) service AMSS aeronautical mobile-satellite service AMTS automated maritime telecommunications system ANA article numbering association ANI automatic number identification ANL automatic noise limiter ANMCC Alternate National Military Command Center ANS ambient noise level American National Standard ANSI American National Standards Institute (formerly ASA) ANT antenna noise temperature AP anomalous propagation applications processor APC adaptive predictive code adaptive predictive coding automatic phase control apd avalanche photodiode a.p.d. avalanche photodiode APD automatic phase control avalanche photodetector avalanche photodiode APDC avalanche photodiode coupler APEX Advanced Project for Information Exchange API application program interface Appendix A 1131 APIICS application program interface/communications service APK amplitude phase-shift keying APL A Programming Language Array Programming Language average picture level APPC Advanced Program-to-Program Communications (IBM) APPN Advanced Peer-to-Peer Networking APSK amplitude phase-shift keying APT Automatically Programmed Tool ARENA Automated Recourse to Electronic Negotiations Archive ARM asynchronous response mode (Link Layer OSI-RM) ARN air reporting net ARNS aeronautical radionavigation service ARNSS aeronautical radionavigation-satellite service ARP address resolution protocol Address Resolution Protocol (standard) ARPA Advanced Research Projects Agency (now DARPA) ARPAnet Advanced Research Projects Agency Network ARPANET Advanced Research Projects Agency Network ARQ automatic repeat-request automatic request for transmission ARR airborne radio relay ARS automatic route selection automatic route selector ARTIC a realtime interface coprocessor ARU audio response unit AS abstract syntaxe aeronautical station ASA American Standards Association (Now ANSI) ASAS all-source analysis system ASC AUTODIN Switching Center axis of signal communications ASCII American Standard Code for Information Interchange ASE automatic switching equipment ASIC application-specific integrated circuit ASN.1 Abstract Syntax Notation 1 (ISO) ASOCnet Army Special Operations Command Network ASP adjunct service point Aggregated Switch Procurement AppleTaJk Session Protocol ASR automatic send and receive Appendix A 1132 ASRT automatic send/receive terminal ASS amateur satellite service automatic switching system ASTM American Society for Testing and Materials AT asynchronous transmission ATACS Army Tactical Communications System (U.S.) ATB all trunks busy (signal) ATC air traffic control air traffic controller ATOM asynchronous time-division multiplexing ATE automatic test equipment ATF advanced tactical (optical) fiber ATM alternative test method alternative test mode asynchronous transfer mode Asynchronous Transfer Mode (standard) automatic teller machine automatic tracking mechanism ATOF advanced tactical optical fiber ATOW acquisition and tracking orderwire ATV advanced television au astronomical unit AU access unit AU! access unit interface attachment unit interface AUTODIN Automatic Digital Network (U.S. 000) AUTOSEVOCOM Automatic Secure Voice Communications Network AUTOVON Automatic Voice Network (U.S. 000) AVO alternate voice/data AVPO axial vapor phase oxidation (process) AWG American Wire Gauge AWGN additive white Gaussian noise AWM appliance wiring material AWSIM air warfare simulation AZ azimuth b bit (binary digit) byte B bel, byte balun balanced-to-unbalanced BAS basic activity set (OSI Session) Appendix A 1133 basecom base communications BASIC beginner's all-purpose symbolic instruction code BB baseband BBC back-to-back connection British Broadcasting Company BBLAN baseband local area network BBS bridge-to-bridge station BCC block check character BCD binary coded decimal BCH Bose-Chaudhuri-Hochquenghem (code) BCI bit count integrity BCS B-channel circuit-switched basic combined set (OSI Session) BCVT basic class virtual tenninal (OSI) Bd baud BEL bell (transmission control character) bell BEL character BEP block error probability BER basic energy reduction bit error rate (errors/time) bit error ratio (errors/characters sent) block error ratio BERT' bit error ratio test bit error ratio tester BES base Earth station BETRS Basic Exchange Telecommunications Radio Service BEX broadband exchange BFlCC British Facsimile Industry Consultative Committee BFL back focal length BFOG Brillouin fiber optic gyroscope BIGFON experimental Gennan video service BIH Bureau International del 'Heure International Time Bureau BIOD Bell integrated optical device BIOS basic input-output system bis second version of a recommendation (CCITr) BISDN broadband integrated services digital network B-ISDN Broadband Integrated Services Digital Network (Standard) bi-sync binary synchronous (communications) bit binary digit BIT built-in test Appendix A 1134 BITE built-in test equipment BID basic infonnation unit (lBM/SNA) bus interface unit BLER block error rate BLERT block error rate test block error rate tester block error rate testing BLP block loss probability BLR block loss ratio BMLC Basic Mode Link Control BMMG British Minicomputer Manufacturing Group BMR bit misdelivery ratio block misdelivery ratio BNF