| AAL | application adaptation layer |
| ABM | asynchronous balanced mode |
| ACK | acknowledgement |
| ACL | asynchronous connectionless link |
| ADSL | asymmetric digital subscriber line |
| AES | advanced encryption standard |
| AH | authentication header |
| AM | amplitude modulation |
| AMI | alternate mark inversion |
| AMPS | advanced mobile phone system |
| ANSI | American National Standards Institute |
| AP | access point |
| ARP | Address Resolution Protocol |
| ARPA | Advanced Research Projects Agency |
| ARPANET | Advanced Research Projects Agency Network |
| ARQ | automatic repeat request |
| AS | authentication server |
| AS | autonomous system |
| ASCII | American Standard Code for Information Interchange |
| ASK | amplitude shift keying |
| ASN.1 | abstract syntax notation 1 |
| ATM | asynchronous transfer mode |
| AUI | attachment unit interface |
| CBS | Committed burst size |
| EBS | excess burst size |
ACRONYMS FOR DATA COMMUNICATIONS
