[Serusers] SIP call hold/unhold

[samuel]

Sending to the list as more people might be interested...

I read offer/answer RFC quite a long ago but as far as I remember
there is no limit in the parameters you can change in a new
offer/answer exchange.
According to this, UA1 can change the port and the media direccion in
the same offer/answer exchange.

Samuel.


2005/12/15, tcchan <tikchoong.chan at redtone.com>:
> Dear Samuel,
>
>
> Thanks you very much for your answer.
>
>
> I would like to consult you the following:
>
> normal call,
>
> UA1 ----- invite --port 30000-------> UA2
>
> UA2 <---------OK port 20000 ---------UA2
>
>
> UA1 hold the call,
>
> UA1 -----invite --port 30000(hold) ----> UA2
>
> UA1 <--------OK port 20000 -------------UA2
>
>
>
>
>
> UA1 unhold the call,
>
> UA1 ------invite -----port 30001 -------> UA2
> UA1 <----------OK port 20000 -----------UA2
>
>
>
> Noticed that when UA1 unhold the call, it uses a different port.
> Is UA1 SIP compliant.
>
> Thanks again and Regards,
>
> TC Chan
>
>
> On Wed, 2005-12-14 at 09:18 +0100, samuel wrote:
> > UA is not SIP compliant. It must include the SDP in the OK.
> >
> > Samuel.
> >
> > 2005/12/14, tcchan <tikchoong.chan at redtone.com>:
> > > Dear All,
> > >
> > > I encountered a UA that behave as follow:
> > >
> > > UA1 call UA2
> > >
> > > UA1 ---- invite with SDP -----> UA2
> > >
> > > UA1 <------OK with SDP --------UA2
> > >
> > >
> > > UA1 hold the call,
> > >
> > > UA1 ------invite (hold)  ------>UA2
> > > UA1 <--------OK but not SDP ---UA2
> > >
> > >
> > > UA1 unhold the call
> > >
> > > UA1 ------invite ----------->UA2
> > > UA1 <-------OK but also no SDP---UA2
> > >
> > >
> > >
> > > I found that most ATA(UA) would attached a SDP when reply an OK whether
> > > the call is hold or unhold.  But there is one ATA that does not (UA2).
> > >
> > >
> > > I noticed that some ATA--Linksys (UA1) would send a BYE to UA2 if it
> > > receive a OK with no SDP in the hold case.
> > >
> > > My Question is :
> > >
> > > Is UA2 behave according to RFC?
> > >
> > >
> > >
> > > Would deeply appreciate if someone could let me know the answer as I
> > > always have trouble reading RFCs...
> > >
> > >
> > > Thanks fot any help available.
> > >
> > > Regards,
> > >
> > > TC Chan
> > >
> > >
> > >
> > >
> > > _______________________________________________
> > > Serusers mailing list
> > > serusers at lists.iptel.org
> > > http://lists.iptel.org/mailman/listinfo/serusers
> > >
> >
>
>
>
>