[Serusers] Can SER 2.0.0-rc1 pstn.cfg file actually work with BYE from PSTN?

[Michal Matyska]

Frank Durda IV píše v Út 29. 09. 2009 v 00:19 -0500:
> The reason SER doesn't appear to work with two interfaces that
> connect to two isolated networks is pretty simple:  If you use
> record_route() and loose_route() to handle the called-party BYE
> and re-INVITEs addressing correctly and fix_nated_contact()
> to straighten out the Contact headers in both directions
> on most messages, SER also inserts two Record-Route: headers,
> which is fine for the direction the Method message is sent in,
> but the order is only good for that direction.  On the replies
> (such as 180/183/200) once you get past the SER, everything
> falls apart.  The two Record-Routes that come out of SER
> (or are just passed-through) are now in the wrong order for
> the side of the isolated networks that the reply is sent out
> of SER to, so the machine receiving them tries to send the
> PRACK/ACK back to SER on the IP address of the other isolated
> network because that Record-Route line appears first, and of
> course you can't get there from here.

I'm sorry I haven't read all the discussion but the paragraph above hit
my eyes and I think you should check whether your client/gateway/etc. is
compliant with RFC3261 chapter 12.1.1 and 12.1.2.

Regarding record-route headers and creating route set:
- UAS gets all headers and builds the route set
- UAC gets all headers REVERSE the order and use it as route set

If it wasn't done this way any request with two or more Record-route
headers (regardless who added them - one proxy both or two proxies on
the path) would be affected and very probably wouldn't reach the other
end.

Michal