Subject: RE: [SIP] More inconsistencies and questions

From: Peter Kjellerstedt <[email-masked]>
Date: Thu, 3 Aug 2000 23:53:01 +0200

> -----Original Message-----
> From: Jonathan Rosenberg [mailto:[email-masked]]
> Sent: 03 August 2000 19:48
> To: Peter Kjellerstedt
> Cc: [email-masked]
> Subject: Re: [SIP] More inconsistencies and questions
> 
> Peter Kjellerstedt wrote:
> > 
> > 3) In 6.47.1 (Via: Requests):
> > 
> >    It is stated that the port specified is the port where the
> >    user agent wishes to receive responses.  But what if TCP is used
> >    as transport protocol.  Should it be the port of the local end
> >    of the TCP connection, or the master TCP port of the user agent?
> >    I assume it is the latter as the client would otherwise be
> >    required to open the connection before being able to create the
> >    message.
> 
> No, its the former. The spec says that if TCP is used, the response
> goes over the same connection as the request. It is only if the 
> server needs to reopen a connection to send a response, that it
> would use the port number in the Via header.

Hmm, now you have me confused. If we have the following two agents:

	Client-A			<----------->	Server-B
	Master TCP Port: 5060				Master TCP Port: 5070
	Sending TCP Port: 4711		

Would the Via that Client-A sends in this case look like:

	Via: SIP/2.0/TCP Client-A:5060

or, would it look like:

	Via: SIP/2.0/TCP Client-A:4711

My expectation was that the TCP conection would be between
Client-A:4711 and Server-B:5070, and that is where the response
would be sent, unless the connection has been closed for some
reason, in which case Server-B would open a new TCP connection
to Client-A:5060. This would imply that it is the first of these
to Via's that is to be used. Am I right? (This, I believe, is
what I tried to convey in my first message above.)

//Peter

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---

From: Jonathan Rosenberg <[email-masked]>
Date: Thu, 03 Aug 2000 23:43:05 -0400

>         Via: SIP/2.0/TCP Client-A:5060

Yes.

>         Via: SIP/2.0/TCP Client-A:4711

No.

> what I tried to convey in my first message above.)

Yes.

-Jonathan R.

-- 
Jonathan D. Rosenberg                       72 Eagle Rock Ave.
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