[Kamailio-Users] Kamailio ignores Via in replies?

Iñaki Baz Castillo ibc at aliax.net
Thu Oct 22 12:21:30 CEST 2009

El Jueves, 22 de Octubre de 2009, Alex Hermann escribió:
> while debugging a problem today I encountered a rather strange issue. The 
> client's UA/router was messing up the Via header, with as result that all 
> the IP's in the Via's were replaced by the public IP of the DSL modem.
> Now the weird part: because of the mangled Via's, the expected result is 
> that the reply would be routed back to the IP of the client. Instead, the 
> replies were still following the "correct" return path through a series of 
> OpenSER/Kamailio proxies. How is this possible?

Being a stateful proxy (when using TM) Kamailio doesn't require to parse and 
extract all the fields of Via header in the reply. By inspecting the Via 
"branch" parameter and CSeq method Kamailio already identifies the existing 
transaction (it has that info in memory) so already know where to route it.

Iñaki Baz Castillo <ibc at aliax.net>

More information about the sr-users mailing list