> are we saying an identical SDP need not be present > as long as the version number is kept the same?
No; the answer SDP must comply with RFC 3264. RFC 4028 does not require non changing offer/answer SDPs; it requires the origin field to not change unless the SDP has changed. RFC 4028 section 7.4: "It is RECOMMENDED that the UPDATE request not contain an offer [4], but a re-INVITE SHOULD contain one, even if the details of the session have not changed. In that case, the offer MUST indicate that it has not changed. In the case of SDP, this is accomplished by including the same value for the origin field as did previous SDP messages to its peer. The same is true for an answer exchanged as a result of a session refresh request; if it has not changed, that MUST be indicated." _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
