Hi, I have some questions regarding the usage of TCP as the transport mechanism for SIP and would be grateful for any views people may have:
Is the transport type used for one transaction in a call to be the same in other transactions of the same call? The RFC3261 section 18.1.1 seems to suggest that the decision regarding transport type should be made at the time of sending a request, i.e. if the request is larger than a certain size then use TCP, such a (large) request could obviously occur in a reinvite after the call was setup using UDP. Alan Johnston's "SIP: Understanding the session initiation protocol" further suggests that each TCP connection should be successively closed/re-opened per transaction. As my area of work is telephony, the idea of opening/closing connections throughout the life of a call seems a little sub optimal given the time taken making a socket API connect call. Do any others agree? Presuming that my understanding of the RFC3261 and A. Johnston's book to be correct (transport type is a per transaction property), is there any mechanism in SIP of forcing an entire call to use the same transport type for all it's transactions. thanks for your time, Matt _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
