Given the restrictions in RFC, all four methods seem invalid.
Before we can change the restrictions in the RFC, it looks to me using
"replaces" is a better approach...
How about this flow:
> Caller Callee
> | |
> | |
> |(1) INVITE with offer |
> |----------------------------> |
> | |
> | |
> |(2) 183 with answer 1 |
> |<-------------------------------|
> | |
> | |
> |(3) PRACK |
> |----------------------------> |
> | |
> | |
> |(4) 200 PRACK |
> |<------------------------------|
> |(5) 200 OK |
> |<---------------------------- |
> | |
> |(6) ACK |
> |---------------------------->|
> | |
> |(7)Re-INVITE(replaces with new call id)
> |<----------------------------|
> | NOTIFY |
|----------------------------->
|BYE(the original call id)
|----------------------------->
> | |
> |(8) 200 OK with SDP |
> |---------------------------->|
> | |
> |(9) ACK |
> |---------------------------->|
-----Original Message-----
From: Paul Kyzivat [mailto:[EMAIL PROTECTED]
Sent: 2006?10?5? 22:52
To: Darshan Bildikar
Cc: [email protected]; [email protected]; 'Retesh Chadha'
Subject: [Sip] Re: [Sip-implementors] Early media query
Darshan Bildikar wrote:
> I don't think that even Method 3 and 4 are OK because they will involve a
> change in the origin line parameter of the SDP and that is not allowed as
> per the RFC.
Which RFC?
I suport Crister's response.
Paul
> BTW, what was the rationale behind not allowing the origin line to change?
> It makes implementing apps like prepaid and CRBT very difficult. Could
> someone please throw some light on this?
>
> -----Original Message-----
> From: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED] On Behalf Of Retesh Chadha
> Sent: Monday, October 02, 2006 5:46 PM
> To: [EMAIL PROTECTED]
> Cc: [email protected]; [email protected]
> Subject: Re: [Sip-implementors] Early media query
>
> Hi Udit
> Of all the methods you have specified, Method 1 and 2 are wrong as per
> the RFC which states that the sdp of all the provisional and 2xx
> response of INVITE should be same if they are present.
>
> Both Method 3 and 4 look fine, with method 4 being better because in
> that case 200 ok for INVITE is only sent when the final negotiation
> (call media) is done.
>
> Hope this helps.
_______________________________________________
Sip mailing list https://www1.ietf.org/mailman/listinfo/sip
This list is for NEW development of the core SIP Protocol
Use [email protected] for questions on current sip
Use [email protected] for new developments on the application of sip
_______________________________________________
Sip-implementors mailing list
[email protected]
https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
