Appendix B. Acronyms and Abbreviations

This appendix identifies abbreviations, acronyms, and initialisms used in this book and in the internetworking industry.

Many of these acronyms and other terms are also described in the Cisco Internetworking Terms and Acronyms resource, available at

1RU one-rack unit

2RU two-rack unit

AAA authentication, authorization, and accounting

ABR Area Border Router

ACE Application Control Engine

ACK acknowledgment

ACL access control list

ACS access control server

AD administrative distance

ADU Aironet Desktop Utility

AES Advanced Encryption Standard

AH Authentication Header

ALG application-level gateway

ANSI American National Standards ...

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