Re: [Sip] [Sip-implementors] 200 OK response for hold with different media capabilities

["Avasarala Ranjit-A20990" <ranjit at motorola.com>]

Hi Paul

The HOLD request is nothing but a re INVITE request indicating HOLD.

Could you give a use case where such a thing may happen? I have not come
across any scenario where in the process of putting remote party on
HOLD, media parameters like IP/codec getting changed.  If this happens,
then it cannot be considered a HOLD request.

So how do u distinguish a HOLD request from a non HOLD one if in both
the cases the media parameters (other than a=.....) change?


Regards
Ranjit

-----Original Message-----
From: Paul Kyzivat [mailto:pkyzivat at cisco.com] 
Sent: Tuesday, August 25, 2009 12:07 AM
To: Avasarala Ranjit-A20990
Cc: sunil.bhagat at wipro.com; sip at ietf.org;
sip-implementors at lists.cs.columbia.edu; sip at core3.amsl.com
Subject: Re: [Sip-implementors] [Sip] 200 OK response for hold with
different media capabilities



Avasarala Ranjit-A20990 wrote:
> no it should not. For a Hold request, you do not send any media 
> capabilities. U only change the existing media description lines to 
> indicate HOLD.

I beg to differ.

Technically there is no HOLD request.
All there is is an offer that offers to change a media attribute, from
sendrecv to sendonly or inactive, or from sendonly or recvonly to
inactive.

The response may change anything that is permitted to be changed in the
answer, given the offer. So it may not add m-lines, but it can certainly
change media addresses, and within limits may change media formats
(codecs).

	Thanks,
	Paul

> Regards
> Ranjit
> 
>  
> 
> ________________________________
> 
> From: sip-bounces at ietf.org [mailto:sip-bounces at ietf.org] On Behalf Of 
> sunil.bhagat at wipro.com
> Sent: Monday, August 24, 2009 3:25 PM
> To: sip at ietf.org; sip-implementors at lists.cs.columbia.edu;
> sip at core3.amsl.com
> Subject: [Sip] 200 OK response for hold with different media 
> capabilities
> 
> 
> 
> Hi All,
> 
>  
> 
> I have a small query related to HOLD request being sent out.
> 
>  
> 
> For a hold request, can gateway respond with different media 
> capabilities in 200 OK response?
> 
>  
> 
> Is the HOLD treated as any normal Re-INVITE?
> 
>  
> 
> Regards,
> 
> Sunil.
> 
>  
> 
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