Hi,

>Lets say A sends an initial SDP offer 1 to B. B accepts the offer and
>sends an SDP answer 1 back to A. Later, A wants to modify the session
>and sends an updated offer 2 (based on previous SDP i.e. SDP 
>offer 1) to B. B rejects the offer using a SIP 4xx response. The session is not
>modified. Again after some time A wants to modify the session. What is
>the previous SDP for A now: is it SDP offer 1 (which was accepted) or
>SDP offer 2 (which was rejected)?

SDP offer 1, which was accepted.

>Also, SIP can be used to reject an SDP offer. How can an SDP answer be
>rejected? The answerer has changed its view of the session 
>when it sends the answer. What if the offerer does not like the answer and 
>rejects it (how is this done?). The 2 agents then have a differing view of the
>session. Am I missing something here?

There is no direct way to reject an answer. So, I guess the offerer can either 
send a new offer, or terminate the call...

Regards,

Christer
LM Ericsson

_______________________________________________
Sip-implementors mailing list
[email protected]
http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors

Reply via email to