[SIPForum-discussion] no response for Invite Request

[Kevin P. Fleming]

On 09/10/2010 09:11 AM, Yellow wrote:
> What shall UAC do if no response received for Invite Request  even after
> retransmission time out ?
> 
> According to my understanding It is not proper for sending CANCEL or Bye?
> 
>  
> 
> Can anybody tell me the answer and which RFC should I refer to.

This is documented in RFC3261. If the UAC has never received a response
to the INVITE, even after the prescribed number of retransmissions, then
it must assume the UAS is not operating, not listening at the
address/port expected, or some other serious error has occurred. The UAC
can do nothing in this situation except drop the INVITE attempt. There
is no place to send a CANCEL to, and a UAC never sends BYE for its own
INVITE until after it has gotten a final response to it.

-- 
Kevin P. Fleming
Digium, Inc. | Director of Software Technologies
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
skype: kpfleming | jabber: kfleming at digium.com
Check us out at www.digium.com & www.asterisk.org