[Serusers] protocol fixup: missing ACK after 200 OK

[Jamie Yukes]

Good points.
Well, now I'm working with a UA that does not ACK 487, 
Anyway, does anyone know how to do this?

# the following is for UAs who are known to have broken handling to 487
onreply_route[3] 
{
    if ( status =~ "487" )
    {
        # t_release( );  #  this doesn't work here
    }
}

On Wed, 23 Jun 2004 14:16:17 +0300, Maxim Sobolev <sobomax at portaone.com> wrote:
> 
> That would be a very wrong thing to do, since calee will have no way to
> tell if no-ACK situation has been caused by the loss of 200 OK in
> transit, in which case it has to re-transmit 200 OK, or by the b0rken
> UAC, that don't send ACK after receiving 200 OK. Therefore, such "fixup"
> will undermine non-broken UAs in the presence of packets loss, which is
> unavoidable in the case when UDP is used.
> 
> The only way to address this problem is to seek resolution from the
> phone vendor.
> 
> Regards,
> 
> Maxim
> 
> 
> Jamie Yukes wrote:
> 
> > I have a user agent that does not ACK after 200 OK.
> > Is it possible to configure SER  to generate an ACK and reply to 200 OK?
> >
> > broken UA   ---- INVITE ---> ser
> >                    <---- 100 ------- ser ---- INVITE ---> gateway
> >                            183                    183
> >                                         ser <--- 200 OK---- gateway
> > broken UA  <---- 200 -----     ser
> >                       <------ 2 way RTP ----------->
> >
> > Call is mostly established, but broken UA does not ACK the 200 OK.
> > Can we generate the following packet?
> >                                          ser --- ACK ---> gateway
> >
> > This would allow the broken UA to interop.
> > Can SER generate this ACK?
> >
> > Thanks,
> > Jamie Yukes
> > 
> > _______________________________________________
> > Serusers mailing list
> > serusers at lists.iptel.org
> > http://lists.iptel.org/mailman/listinfo/serusers
> >
> >
> >
> 
>