O'Reilly logo

Signaling System No. 7 (SS7/C7): Protocol, Architecture, and Services by Jeff Hewett, Lee Dryburgh

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Appendix B. ISUP Messages (ANSI/UK/ETSI/ITU-T)

The table in this appendix summarizes ISDN User Part (ISUP) messages and the purpose of each. For an introduction to ISUP, refer to Chapter 8, “ISDN User Part (ISUP).”

Table B-1. ISUP Messages

Message/Code

Full Message Name

Purpose

ACM

0 0 0 0 0 1 1 0

Address Complete

Sent in the backward direction, indicating that all address signals have been received and that the call set-up is progressing.

ANM

0 0 0 0 1 0 0 1

Answer

Sent in the backward direction to indicate that the called party has answered the call. May be used to trigger billing and measurements of call duration.

APM (NI99)(I)

0 1 0 0 0 0 0 1

Application Transport

Sent in either direction to convey application information using the Application Transport ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required