Knowledgebase: Unified Communications
Calls disconnected after 32 sec
Posted by Marc Aeberhard, Last modified by Daniel Lizaola on 20 November 2017 04:14 PM

In some cases SIP calls are disconnected after 32 seconds.

This happens when the SmartNode involved is B side of the connection.
Looking at a debug log of such a call, it can be seen that several 200 OK and ACK messages are sent back and forth.
This is becuase the other device the SmartNode is communicating with, does not follow the SIP standard as per RFC3261.
See the following explanation;

The reason why the ACK for the 200 Ok from the SmartNode is not accepted, is due to an invalid branch ID in the via header.
Based on the description in RFC 3261, the branch ID for a 2xx response has to be different than in the former messages.
You will find this in section, in the RFC 3261.

(1984 vote(s))
Not helpful

Comments (0)
Post a new comment
Full Name:
CAPTCHA Verification 
Please enter the text you see in the image into the textbox below (we use this to prevent automated submissions).