Re: [sipcore] Open issues in draft-ietf-sipcore-sip-websocket-09

Hi Inaki,

I have mentioned earlier (http://www.ietf.org/mail-archive/web/sipcore/current/msg05614.html) that the issue raised by me is related to SIP routing and you are mixing it with NAT & Firewall.

In case you wish to cover the issue in the holistic way, Please suggest the complete text.

I have disagreement for the statement that SIP over SCTP does not document those issue, so SIP over WebSocket will not document the same. 

Thanks
Partha

PS: I have work experience in SCTP transport with RR added by proxy to overcome this issue.

> -----Original Message-----
> From: sipcore-bounces@ietf.org [mailto:sipcore-bounces@ietf.org] On
> Behalf Of Iñaki Baz Castillo
> Sent: Friday, July 05, 2013 3:07 PM
> To: Paul Kyzivat
> Cc: SIPCORE (Session Initiation Protocol Core) WG
> Subject: Re: [sipcore] Open issues in draft-ietf-sipcore-sip-websocket-
> 09
> 
> Please, let me insist even a bit more on it:
> 
> 
> 
> 2013/7/5 Iñaki Baz Castillo <ibc@aliax.net>:
> > Any TCP SIP UA is capable of listening for incoming connections but
> > that does not mean that the proxy should not R-R. If the UA is behind
> > NAT then RFC 5626 must be used (I avoid here proprietary similar
> > mechanisms), and RFC 5626 *alreay* mandates R-R for such a mechanism
> > to work. If GRUU is also in use then the proxy can decide not to R-R
> > (not needed since incoming requests will arrive via the registration
> > path which will of course include Outbound stuff).
> 
> 
> 
> a) If the SIP-WS UA runs in a browser then the website developer can
> make usage of RFC 5626 so the UA *requests* Outbound usage to its
> proxy.
> 
> b) If the SIP-WS UA runs in a desktop and is both a SIP WS Client and
> SIP WS Server (and let's assume it has public IP) then it can avoid
> requesting Outbound to the proxy. If the proxy does R-R it is because
> the proxy wants to be in the patch of the dialog (local policy) and
> not because it is required for the dialog to work.
> 
> 
> Of course, in case b), if the peer does not speak WS and the proxy
> does not R-R here we have a problem, but this is *exactly* the same
> problem as if the caller was a UA using SCTP in its Contact URI. So
> again, this is about local policy in the proxy whether to decide it
> does R-R or not.
> 
> I don't find "Record-Route" word in RFC 4168 so I expect there should
> be no "MUST" keyword about Record-Route in
> draft-ietc-sipcore-sip-websocket. Let me know if I'm wrong.
> 
> 
> 
> Summarizing:
> 
> - This is not an issue introduced by this new WS transport.
> - The issue is not new.
> - There are already standard mechanism to make it to work (the
> *client* can request them to the proxy !).
> - I see no reason at all to mandate nothing in the sip-ws draft about
> this.
> - Guidelines section in the draft already covers it in an informative
> way.
> 
> 
> 
> Hope I am right.
> 
> Best regards.
> 
> 
> 
> --
> Iñaki Baz Castillo
> <ibc@aliax.net>
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