[Sip-implementors] client using Via with sent-by port != src port
Jeroen van Bemmel
jbemmel at zonnet.nl
Thu Sep 29 18:44:55 EDT 2005
I discovered that some clients (in particular: Windows Messenger RTC/1.3, which follows an older SIP version and is not RFC3261 compliant) send requests over UDP from a different source port than announced in the Via header. This is normally not a problem, but upon shutdown the client seems to close the port mentioned in the Via, so the response is never received and the unREGISTER is repeated several times
I don't get an ICMP port unreachable though, they seem to get supressed
My solution was to treat the request as if it had an 'rport' flag in the Via header; would this be advisable in general?
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