[reSIProcate] Problem with UAC sending ACK automatically

[Adam Roach]

Kovar, William (Bill) wrote:
> Because even after a 200 OK is received, the call can still be rejected by the far end... i.e. Cust hangs up before ACK is sent.
>   

Right. But even in these cases, you need to send an ACK. It's not 
reasonable (or compliant) to decide to withhold the ACK as an indication 
that the call setup has failed. Under those circumstances, you need to 
send an ACK followed immediately by a BYE.

I reiterate once more that an ACK without an SDP body is a 
transport-level consideration and must, must, must not be of interest to 
the application. If it is, you've done something wrong with your design.


/a