Another scenario is a route failure. If a stateless proxy sees a route is invalid (on the second attempt, call to send returns error due to ICMP received after the first send attempt) it will want to send 4xx upstream.
The stateless proxy should not try to forward a subsequent ACK though. Which means the proxy should keep hunting ACKs with To-tags owned by it. How about a stateless redirect server? It seems to me very similar to a stateless UA sending 4xx. However, bis-05 says in S 8.3 "The redirect server maintains transaction state for the whole SIP transaction." Can someone remind me why? -Jiri At 05:16 AM 11/1/2001, Jonathan Rosenberg wrote: [...] >Stateless proxy is just a ROLE. If an element needs to generate a response, >it becomes a UAS. We have tried to make that consistently clear in bis-04. > >That said, it is possible for a UAS to statelessly generate a response. Each >request retransmission would trigger the response to be recomputed and >re-sent. This only works if the element never generates a 1xx, but rather >responds with the final response right away. This is used, for example, to >prevent unauthenticated requests from creating state in servers. >[...] >> A stateless proxy receives an INVITE and doesn't have any destination >> for it. What is it supposed to do? Generate 4xx upstream? >> Then who takes >> care of the retransmission stuff? Note that this is a >> stateless proxy -- >> no call state, no transaction state. Or does it silently discard the >> INVITE? Or does it dump the INVITE onto a UAS and let the UAS do the >> dirty job? Doesn't sound elegant, though. -- Jiri Kuthan http://iptel.org/~jiri/ _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
