Or use TCP as your transport, and make sure you use the 'alias'
option in your Via, defined in draft-ietf-sip-connect-reuse-04.txt.

This should ensure that further requests get sent over the same TCP
connection, back to UA1.

Regards,

Michael Procter

> -----Original Message-----
> From: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED] Behalf Of 
> Jeroen van
> Bemmel
> Sent: 28 September 2005 07:41
> To: Joseph Cheri; [email protected]
> Subject: Re: [Sip-implementors] Traversal of SUBSCRIBE/NOTIFY
> requeststhroughSymmetric NAT
> 
> 
> Hi Joseph,
> 
> I think that for this to work, you would need an entitty 
> (proxy or ALG) at 
> the NAT box. An ALG would replace the private IP in the 
> Contact header of 
> the SUBSCRIBE with a public one, a proxy would record-route 
> the SUBSCRIBE 
> such that it receives the NOTIFY on its public IP address
> 
> Regards,
> 
> Jeroen
> 
> ----- Original Message ----- 
> From: "Joseph Cheri" <[EMAIL PROTECTED]>
> To: <[email protected]>
> Sent: Wednesday, September 28, 2005 6:47 AM
> Subject: [Sip-implementors] Traversal of SUBSCRIBE/NOTIFY requests 
> throughSymmetric NAT
> 
> 
> >
> > Hi All,
> >
> >
> >
> > Can anyone please provide me pointers for the below 
> mentioned query ?
> >
> >
> >
> > 1> Consider the following deployment scenario
> >
> >
> >
> > [UA1] ---->NAT---->Presence Server--->[UA2]
> >
> >
> >
> > Let us assume that UA1 is in private domain and is behind a 
> symmetric NAT. 
> > And the remaining entities (i.e. Presence Server and UA2) 
> are in public 
> > domain.
> >
> >
> >
> > Suppose that UA1 (watcher) is not registered and wants to 
> subscribe to UA2 
> > through Presece server.  Now as NAT is present the response 
> 200 OK for 
> > subscribe request will follow the same path and reach 
> UA1(may be using 
> > rport or the same connenction incase of connection oriented 
> transport). 
> > But for NOTIFY how does the call flow actually happens? The 
> NOTIFY is 
> > always sent on 'Contact' received in SUBSCRIBE request, and 
> can be a 
> > private IP. Hence NOTIFY sent to the private conatct will 
> be dropped at 
> > NAT. So shall the NOTIFY be sent on 'received' and 'rport' 
> received in 
> > initial SUBSCRIBE request ?
> >
> >
> >
> >>Is it that its possible to sent UA1 a NOTIFY only if UA1 
> sends a subscribe 
> >>with an rport paramter?
> >
> >>Is it that the UA1 sends a subscribe request with 
> instance-id and flow-id? 
> >>(is this allowed // instance-id and flow-id are for 
> Registration request)
> >
> >
> >
> > or is there any other solution for the same.
> >
> >
> >
> > Regards,
> >
> > --Jose
> >
> >
> >
> > ---------------------------------
> > Yahoo! India Matrimony: Find your partner now.
> > _______________________________________________
> > Sip-implementors mailing list
> > [email protected]
> > http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors 
> 
> _______________________________________________
> Sip-implementors mailing list
> [email protected]
> http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
> 

_______________________________________________
Sip-implementors mailing list
[email protected]
http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors

Reply via email to