August 1999
Intermediate to advanced
328 pages
8h 50m
English
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THE H.323 SPECIFICATION
Many VoIP vendors are using the ITU-T H.323 recommendation (or a subset) in their products. In a few short years, it has become the standard for deploying VoIP in a local area network.
H.323 for VoIP encompasses considerably more than one H.323 specification. Other H-Series recommendations come into play, such as H.225.0 and H.245. The focus of attention for the first part of this chapter is H.323, but the other pertinent H-Series recommendations are also explained.
The H Series use Abstract Syntax Notation.1 (ASN.1) to describe messages. From previous experience, I know that few readers understand ASN.1. So, I have kept the ASN.1 examples to a minimum. I provide a brief tutorial on ASN.1, and I explain each element (field) ...