[Kamailio-Users] UAC on ACK in reInvite

[Schober Walter]

See below...

> -----Original Message-----
> From: Klaus Darilion [mailto:klaus.mailinglists at pernau.at] 
> Sent: Wednesday, November 26, 2008 1:21 AM
[...]
> 
> This is clearly a bug in the useragent. The route set must not be 
> changed with reINVITEs. Thus, according to the standard the 
> Record-Route 
> headers for indialog requests are not needed. Maybe you are calling 
> record_route() for indialog requests and this confuses the client.
Fully agree on this. But some proxies add Record-Route, some don't,
Openser/Kamailio can configure it.

It's not that clear in the RFC, but I see it the same way:
RFC 3261, 12.2 Request within a Dialog
...
   Requests within a dialog MAY contain Record-Route and Contact header
   fields.  However, these requests do not cause the dialog's route set
   to be modified, although they may modify the remote target URI.

12.2.1.2 Processing the Responses
-> The only thing mentioned is that the _Target URI_ gets refreshed by
the 200 OK. 

=> reInvites do not modify the routeset of any subsequent request,
neither the ACK not any other upcoming request.

> Try removing the record_route() for indialog requests - may then the 
> buggy client remembers the original route set.
Done. Client sends ACK on reInvite directly then :-( Counterpath is OK,
Teles Voipbox not, other clients to be tested ...

So I will have to add vsf uri param from Route to record route in the
proxy. This at least is a reason to upgrade :-) It's done more easily
with tranformations.

Thanks for the discussion! For me it's "clearly a bug in the UA" now,
too ;-) However, let's find a workaround.

br
Walter