Videoconferencing Demystified: Making Video Services Work

| AAL | ATM Adaptation Layer |
| AARP | AppleTalk Address Resolution Protocol |
| ABM | Asynchronous Balanced Mode |
| ABR | Available bit rate |
| AC | Alternating Current |
| ACD | Automatic Call Distribution |
| ACELP | Algebraic Code-Excited Linear Prediction |
| ACF | Advanced Communication Function |
| ACK | Acknowledgment |
| ACM | Address Complete Message |
| ACSE | Association Control Service Element |
| ACTLU | Activate Logical Unit |
| ACTPU | Activate Physical Unit |
| ADCCP | Advanced Data Communications Control Procedures |
| ADM | Add/Drop Multiplexer |
| ADPCM | Adaptive Differential Pulse Code Modulation |
| ADSL | Asymmetric Digital Subscriber Line |
| AFI | Authority and Format Identifier |
| AIN | Advanced Intelligent Network |
| AIS | Alarm Indication Signal |
| ALU | Arithmetic-logic unit |
| AM | Administrative Module (Lucent 5ESS) |
| AM | Amplitude Modulation |
| AMI | Alternate Mark Inversion |
| AMP | Administrative Module Processor |
| AMPS | Advanced Mobile Phone System |
| ANI | Automatic Number Identification (SS7) |
| ANSI | American National Standards Institute |
| APD | Avalanche Photodiode |
| API | Application Programming Interface |
| APPC | Advanced Program-to-Program Communication |
| APPN | Advanced Peer-to-Peer Networking |
| APS | Automatic Protection Switching |
| ARE | All Routes Explorer (Source Route Bridging) |
| ARM | Asynchronous Response Mode |
| ARP | Address Resolution Protocol (IETF) |
| ARPA | Advanced Research Projects Agency |
| ARPANET | Advanced Research Projects Agency Network |
| ARQ | Automatic Repeat Request |
| ASCII | American Standard Code for Information Interchange |
| ASI | Alternate Space Inversion |
| ASIC | Application Specific Integrated Circuit |
| ASK | Amplitude Shift Keying |
| ASN | Abstract Syntax Notation |
| ASP | Application Service Provider |
| AT&T | American Telephone and Telegraph |
| ATDM | Asynchronous Time Division Multiplexing |
| ATM | Asynchronous Transfer Mode |
| ATM | Automatic Teller Machine |
| ATMF | Asynchronous Transfer Mode Forum |
| AU | Administrative Unit (SDH) |
| AUG | Administrative Unit Group (SDH) |
| AWG | American Wire Gauge |
| B8ZS | Binary 8 Zero Substitution |
| BANCS | Bell Administrative Network Communications System |
| BBN | Bolt, Beranak, and Newman |
| BBS |