IMG 1010 - Multiple SIP 183s prior to 200 OK

Overview:

The IMG supports receiving multiple SIP 183 responses prior to a 200 OK for an INVITE request, when SIP responses can potentially be received from multiple remote user agents. A proxy or an Application server that receives an INVITE from the IMG can then fork the request to multiple destinations.

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When the Comedia Mode is set to Passive, the outbound RTP packets are to be sent to the second RTP destination, even if the first destination continued to send RTP packets. If Comedia Mode is set to active, the IMG behavior is to be the same as if it were disabled.

See IMG 1010 - Symmetric NAT Traversal for more information on Comedia Mode.

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