Call Processing Of Sip Dialog Requests - AudioCodes Mediant 4000 SBC User Manual

User's Manual
21.3

Call Processing of SIP Dialog Requests

The device processes incoming SIP dialog requests (SIP methods) such as INVITE,
SUBSCRIBE, OPTIONS, REFER, INFO, UNSOLICITED NOTIFY, MESSAGE, and
REGISTER. The process is summarized in the following figure and subsequently
described:
The SIP dialog-initiating process consists of the following stages:
1. Determining Source and Destination URL: The SIP protocol has more than one
URL in a dialog-initiating request that may represent the source and destination URLs.
The device obtains the source and destination URLs from certain SIP headers. Once
the URLs are determined, the user and host parts of the URLs can be used as
matching rule characteristics for classification, message manipulation, and call routing.
Version 7.2
Figure 21-2: SBC Call Processing
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21. SBC Overview
Mediant 4000 SBC