From: "Gaurav Kheterpal" <[EMAIL PROTECTED]> How does the UAS decide what to do out of the above 2 options?
The implementor chooses which suits his purposes better. "I assume that the reason for this response is that a forwarded call might have a longer set-up time (until a 180 is returned to the UAC) than usual, so the UAS wishes to reassure the UAC that the call is making progress." I'm not sure the logic of sending a 3xx after a 181 goes too well based on the above statement. If a UAC receives a 181, it already knows that the call is being forwarded. In that case, it would not be expecting a response from the original destination anyway so what value would a 3xx response add? When the nearest intermediate proxy (or perhaps the UAC if there is no intermediate proxy) receives a 3xx, it will then create further forks of the dialog to attempt to contact the addresses provided in the 3xx message. In scenario 2, that is how the UAS that desires to forward the call accomplishes the forwarding without having to act as a proxy itself. Dale _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
