Re: [Simple] MSRP O/A refresh question

[Ruud Klaver <ruud at ag-projects.com>]

Hi Paul,

On Oct 30, 2007, at 6:24 PM, Paul Kyzivat wrote:

> While reviewing the latest version of the file transfer draft I  
> developed some doubts about MSRP that I want to check:
>
> RFC4975, section 8.4 talks about updated SDP offers. I want to  
> double check my interpretation of this section.
>
> Suppose Alice makes an initial offer to Bob for an MSRP session,  
> and Bob accepts. At that time Alice is required to do the Connect  
> to Bob.
>
> Later, Bob has need to refresh the sip session with a reinvite, but  
> has no desire to change anything about the MSRP session. So Bob  
> sends an offer with an unchanged o-line. Alice doesn't want to  
> change anything either, and so answers with an unchanged o-line.
>
> By my reading, its required that Bob now connect to Alice. Even  
> though neither wants to change anything there is need to establish  
> a new connection, and presumably to drop the old one.
>
> Is that right???
>
> If not, where is some other behavior called out?
>
> 	Thanks,
> 	Paul

If I understand the RFC correctly, I think this is what should happen:

If Bob wishes to refresh an already existing MSRP session, I think he  
should include exactly the same MSRP path attribute in the SDP as he  
did for the initial session negotiation. As this includes session  
identifiers unique to this session, Alice will be able to determine  
that this session is already established and no action should be  
taken, besides replying with a SIP OK with her own MSRP path in the SDP.


Best Regards,
Ruud Klaver


_______________________________________________
Simple mailing list
Simple at ietf.org
https://www1.ietf.org/mailman/listinfo/simple