[OpenSER-Devel] [Serdev] Possible bug in the tm module in the presence of packet loss/branches

[Maxim Sobolev]

Dan Pascu wrote:
> Even if a CANCEL arrives, a call may still be setup with a 200 OK + and 
> ACK and then immediately closed by a BYE, which is a conceptually a 
> completely different beast that a simple CANCEL that terminates the call 
> without it being setup.

No, you are incorrect, it has been a possibility to get call setup with 
200 OK after CANCEL even with the previous behavior. When there are 
confirmed outgoing branches the proxy did not generate 487 locally, but 
instead relied CANCEL to them and waited for all of them to complete 
with either positive or negative final reply. The only case when local 
487 was generated before is when CANCEL arrives when all outgoing 
branched have not generated any provisional response yet.

Regards,
-- 
Maksym Sobolyev
Sippy Software, Inc.
Internet Telephony (VoIP) Experts
T/F: +1-646-651-1110
Web: http://www.sippysoft.com