> However should the UAS continue to retransmit > 482 until it received an ACK for 482?
Yes. The RFC does not explicitly disable the retry mechanism for 482. However if no 1xx was sent prior to the 482, I assume some vendors might use the 401/407 "retry" mechanism. > 1. How is it different between an ACK for 482 > and an ACK for 200 OK for original (first) INVITE? If it occurred outside of dialog, you can provide and use a different To tag. If it occurred within a dialog, transaction matching based upon the Via branch can be used. ACK for non-2xx must have the same branch. ACK for 2xx must have a different branch. > 2. What happen if the original call is going > to teardown before the max retries timeout reach > for 482 (2nd INVITE)? The retries should continue. However it is mainly an implementation detail (assuming no 1xx) since the INVITE will be resent if the device really wants the final response. _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
