[SR-Users] t_relay_cancel usage

[Andrei Pelinescu-Onciul]

On Oct 07, 2010 at 15:52, Juha Heinanen <jh at tutpro.com> wrote:
> Andrei Pelinescu-Onciul writes:
> 
> > > if proxy is processing all invites statefully, why anything needs to be
> > > done when invite transaction corresponding the to cancel is missing?
> > > isn't it a case of unmatched cancel and the cancel could just be
> > > dropped?
> > 
> > Well, IMHO it should be forwarded the same as one would forward the
> > INVITE. Dropping it is quite a hardliner approach :-)
> 
> andrei,
> 
> i would challenge invite, but can't do that for cancel.  what is the
> advantage of becoming an open unmatched cancel relay?

www_authenticate() will return "authenticated" for ACK, CANCEL and
PRACK. So unless you are using something different it would be difficult
to challenge the CANCEL :-)

It's possible to have a miss-routed CANCEL and in general I'm for a more
relaxed approach: let CANCELs or ACKs that we don't know anything about
pass through.
Of course there are exception, like if the CANCEL is for some internal
 gateway or something similar, but in general I would let them pass.

Andrei