Comment at end.
Paul
[EMAIL PROTECTED] wrote:
Consider the following prepaid card application scenario::
Assuming party A and B are talking and following steps occur:
i) Party B hung up.
ii) B2BUA end the dialog with user B and connect user A to media server using REINVITE asking for another number.
iii) After A presses the digits, B2BUA initiates a new dialog for user C
iv) When party C is ringing, B2BUA sends 180 Ringing to agent A.
User A B2BUA User B Media Server
| |(1) BYE | |
| |<------------------| |
| |(2) 200 | |
| |------------------>| |
| | | |
| | | |
|(3) INV no SDP | | |
|<------------------| | |
|(4) 200 offer2 | | |
|------------------>| | |
| |(5) INV offer2 | |
| |-------------------------------------->|
| |(6) 200 answer2 | |
| |<--------------------------------------|
|(7) ACK answer2 | | |
|<------------------| | |
| |(8) ACK | |
| |-------------------------------------->|
|(9) RTP | | |
| (Connected to media server, user A dials digits) |
|...........................................................|
| |(10) BYE | |
| |-------------------------------------->|
| |(11) 200 OK | |
| |<--------------------------------------|
| |(12) INV no SDP | User C |
| |-------------------|-------->| |
| | (13) 180 Ringing | | | | (14)180 Ringing?? |<------------------|---------| |
|<------------------| | | |
| |(15) 200 offer3 | | |
| |<------------------|---------| |
|(16) INV offer3' | | | |
|<------------------| | | |
|(17) 200 answer3' | | | |
|------------------>| | | |
| |(18) ACK answer3' | | |
| |-------------------|-------->| |
|(19) ACK | | | |
|<------------------| | | |
|(20) RTP | | | |
|.......................................|.........| |
My question is what will happend for message F14.
Use agent A invite and reinvite transactions are already completed and the dialog is in cofirmed state. However as per application, the behaviour should be like calling party A is now initiating the call to user C and A should hear the ringback.
So if it receives provisional response, what should be the behaviour, is it mentioned somewhere in RFC?
I see one obvious problem with the above. It isn't valid to be sending a 180 at (14). There is no active transaction for it to be a response to. At best you could rearrange things, moving the (14) down or (16) up so the 180 is part of the reinvite transaction.
But no matter what you do, I don't think there is any defined way to get A to generate local ringback in this situation.
Paul _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
