Re: [Msrp] Connection Sharing in MSRP
Hi Ben,
How we interpret multiple MSRP sessions reusing the same port is in case of
IM applications
its possible for the SDP to contain multiple m lines indicating different
types of data which the application
wants to share with his/her peer. When IM establishes the session through
SIP, it can spawn multiple
MSRP sessions for handling different kinds of data say file data and text
messages. I guess this is a
very valid scenario for reusing of connection across different MSRP session.
Please give us your opinion on this.
Thanks,
Ashok
----- Original Message -----
From: "Ben Campbell" <ben@xxxxxxxxxxxx>
To: "Sudha" <sudha.vs@xxxxxxxxxxxxxxxxxx>
Cc: <msrp@xxxxxxxxxxxxxxxxxxx>
Sent: Monday, February 06, 2006 9:27 PM
Subject: Re: [Msrp] Connection Sharing in MSRP
>
> On Feb 6, 2006, at 9:07 AM, Sudha wrote:
>
> > Hi All,
> >
> > With Reference to draft-ietf-simple-message-sessions-2.txt
>
> First, you are looking at a very old draft--the current one is draft-
> ietf-simple-message-sessions-13. A version 14 will be coming out
> shortly, but I do not expect it to contain any substantive changes.
>
> >
> > "When an MSRP endpoint wishes to send a request to a peer
> > identified by an MSRP URL, it first needs a transport connection,
> > with the appropriate security properties, to the host specified in
> > the URL. If the sender already has such a connection, that is, one
> > associated with the same host, port, and URL scheme, then it SHOULD
> > reuse that connection."
> >
> > In this case,
> >
> > If the Source Port, Target Port, Source IP, Traget IP and security
> > scehme of a particular connection matches it can be reused.
> >
> > Hence same connection can be used by 2 or more sessions each of
> > them having differnt Session IDs.
> >
> > My doubt here is when does such a scenario arise? The msrp URLs are
> > given by SDP. The SDP doesnt reuse the same port in the MSRP URL
> > when it is already in Use.
> >
> > Can you please help me on understanding the scenario when MSRP
> > Connection sharing may occur.
>
> The SDP certainly can reuse the same MSRP port if an implementation
> chooses to do so. But the real use of this is for when relays are
> involved. You could have any number of MSRP sessions with multiple
> peers going across the same outbound relay. In this case, you should
> not create a separate TCP connection to that relay for each of the
> sessions. This is even more true for connections between an adjacent
> pair of relays that may carry any number of active sessions.
>
> Hope this helps.
>
> Ben.
>
>
> _______________________________________________
> msrp mailing list
> msrp@xxxxxxxxxxxxxxxxxxx
> https://list.sipfoundry.org/mailman/listinfo/msrp
>
>