This behavior is documented in section 13.2.2 of RFC 3261 Processing INVITE 
Responses. Specifically the paragraph that talks about handling a 2xx 
responses. Once you have "ACK"ed the first 2xx response you start a 64*T1 
timer at the end of which all 'early' dialogs transition to 'terminated' 
state. 

As regards handling multiple 2xx responses, a UA MUST send an ACK and then 
send BYE's on dialogs that it doesn't want to continue. As to which of the 
2xx response a UA accepts is implementation dependent..


 On 4/20/05, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: 
> 
> 
> Commnets inline 
> 
> 
> I don't think you need to create an early dialog when you receive the 180 
> at
> F5. Per section 13.2.2 of RFC 3261 you will need to create an early dialog
> on a 1xx response only if you want to exchange messages with the peer 
> prior
> to completion of the INVITE transaction. Having said that, should you 
> create
> early dialogs to accomplish exchanging messages prior to completion of
> INVITE transaction, I would think that all your early dialogs terminate 
> when
> you get a final response for the INVITE.
> 
> *>> Is this behaviour mentioned somewhere in RFC where UA can terminate 
> all the early* 
> *>> dialogs created if it receives final response.* 
> *>> I think same issue will be there for confirmed dialogs if *
> *>> UA receives multiple 2xx responses (may be due to forking proxy) 
> having different *
> *>> To-tags, resulting in establishment of different confirmed dialogs.* 
> *>> Is it UA-specific behaviour to deal with this situation and pick the 
> first 2xx response* 
> *>> and terminate the other dialogs by either sending BYE or CANCEL. *
> 
> 
> On 4/20/05, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
> >
> >
> > I have a question in the below sceanrio in Service-examples draft,
> > What will be the behaviour of Alice user agent on receiving messages F5,
> > F10 and F13.
> >
> > These responses have same Via branch parameter but different To tag 
> hence
> > it will result in different dialog creation. How will UA deal with these
> > dialogs? And if multiple dialogs are created, then will the first dialog
> > created by F5 terminate after timeout?
> >
> > 2.8 Call Forwarding - No Answer
> >
> > Alice Proxy User B1 User B2
> > | | | |
> > | INVITE F1 | | |
> > |--------------->| INVITE F2 | |
> > |(100 Trying) F3 |------------->| |
> > |<---------------|180 Ringing F4| |
> > | 180 Ringing F5 |<-------------| |
> > |<---------------| | |
> > | Request Timeout |
> > | | | |
> > | | CANCEL F6 | |
> > | |------------->| |
> > | | 200 OK F7 | |
> > | |<-------------| |
> > | | 487 F8 | |
> > | |<-------------| |
> > | | ACK F9 | |
> > | |------------->| |
> > |(181 Call is Being Forwarded) F10 |
> > |<---------------| | INVITE F11 |
> > | |--------------------------------->|
> > | | | 180 Ringing F12 |
> > | 180 Ringing F13|<---------------------------------|
> > |<---------------| | 200 OK F14 |
> > | |<---------------------------------|
> > | 200 OK F15 | | |
> > |<---------------| | |
> > | ACK F16 | | |
> > |--------------->| | ACK F17 |
> > | |--------------------------------->|
> > | Both way RTP Established |
> > |<=================================================>|
> > | BYE F18 | | |
> > |--------------->| | BYE F19 |
> > | |--------------------------------->|
> > | | | 200 OK F20 |
> > | 200 OK F21 |<---------------------------------|
> > |<---------------| | |
> > | | | |
> >
> >
> > F5 180 Ringing Proxy -> Alice
> >
> > SIP/2.0 180 Ringing
> > Via: SIP/2.0/TLS 
> > client.atlanta.example.com:5061<http://client.atlanta.example.com:5061/>
> <http://client.atlanta.example.com:5061/>
> > ;branch=z9hG4bK74bf9
> > ;received=192.0.2.103 <http://192.0.2.103/> <http://192.0.2.103/>
> > Record-Route: <sips:ss1.example.com <http://ss1.example.com/> <
> http://ss1.example.com/>;lr>
> > From: Alice <sips:[EMAIL PROTECTED]>;tag=1234567
> > To: Bob <sips:[EMAIL PROTECTED]>;tag=3145678
> > Call-ID: [EMAIL PROTECTED]
> > CSeq: 1 INVITE
> > Contact: <sips:[EMAIL PROTECTED]>
> > Content-Length: 0
> >
> > F10 (181 Call is Being Forwarded) Proxy -> Alice
> > SIP/2.0 181 Call is Being Forwarded
> > Via: SIP/2.0/TLS 
> > client.atlanta.example.com:5061<http://client.atlanta.example.com:5061/>
> <http://client.atlanta.example.com:5061/>
> > ;branch=z9hG4bK74bf9
> > ;received=192.0.2.103 <http://192.0.2.103/> <http://192.0.2.103/>
> > From: Alice <sips:[EMAIL PROTECTED]>;tag=1234567
> > To: Bob <sips:[EMAIL PROTECTED]>
> > Call-ID: [EMAIL PROTECTED]
> > CSeq: 1 INVITE
> > Content-Length: 0
> >
> > F13 180 Proxy -> Alice
> > SIP/2.0 180 Ringing
> > Via: SIP/2.0/TLS 
> > client.atlanta.example.com:5061<http://client.atlanta.example.com:5061/>
> <http://client.atlanta.example.com:5061/>
> > ;branch=z9hG4bK74bf9
> > ;received=192.0.2.103 <http://192.0.2.103/> <http://192.0.2.103/>
> > Record-Route: <sips:ss1.example.com <http://ss1.example.com/> <
> http://ss1.example.com/>;lr>
> > From: Alice <sips:[EMAIL PROTECTED]>;tag=1234567
> > To: Bob <sips:[EMAIL PROTECTED]>;tag=765432
> > Call-ID: [EMAIL PROTECTED]
> > CSeq: 1 INVITE
> > Contact: <sips:[EMAIL PROTECTED]>
> > Content-Length: 0
> >
> >
> > Regards,
> > Udit
> > _______________________________________________
> > 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
> >
> >
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