[Sip-implementors] Timeout of INVITE- send BYE?

[Ulrich Prakash]

Hi,
I have some queries regarding Timeout of INVITE.

This is my understanding regarding what is to be done on INVITE timeout.
A UAC sends an INVITE through UDP to a UAS.
The destination(UAS) does not exists.
Hence, the INVITE is retransmitted till it gets timed out.
On timeout,send BYE and terminate the call.

UAC     -------INV-------->
        -------INV-------->
               ......
        -------INV-------->

On timeout of INVITE,
        -------BYE-------->
        -------BYE-------->
              ......
        -------BYE-------->

On timeout of BYE,
we clear up the call.

Query 1:
------------
Is this the correct interpretation?

This interpretation is based on the following extract from the draft(bis-09):
Section:12.2.1.2 Processing the Responses of Bis-09:(line 2007)
 A UAC SHOULD also terminate a dialog if no response 2007
at all is received for the request (the client transaction would inform the TU about the timeout.) 2008
For INVITE initiated dialogs, terminating the dialog consists of sending a BYE. 2009

Query 2:
------------
If the above interpretation is correct,then I require a clarification.
In the text quoted,it is said that " A UAC SHOULD also terminate a dialog ....".

In our case, a dialog is not created,since the other end has not responded.

Am I missing something or is something missed out here?

I am attaching the "Creation of a Dialog" text below:

12.1 Creation of a Dialog

   Dialogs are created through the generation of non-failure responses

   to requests with specific methods. Within this specification, only

   2xx and 101-199 responses with a To tag to INVITE establish a dialog.

   A dialog established by a non-final response to a request is in the

   "early" state and it is called an early dialog.

It would be very helpful, if someone could clarify my query.

Thanks & regards,
Ulrich Prakash.