Subject: Re: [Sip] [Sipping] Pls clarify on session timer

From: "Avasarala Ranjit-A20990" <[email-masked]>
Date: Fri, 13 Mar 2009 19:52:57 +0800

Hi Prakash
 
The Server sends a 420 when it doesn't support "timer" option-tag. so
its working fine when you remove it from your request.
 
As per section 7.1 of RFC 4028, the UAC SHALL include a Require header
with option-tag as "time" in the initial INVITE when it wants the server
to support session timer - but this does not necessarily mean that UAC
wants the server to perform refresh - but only wants the server to
support the session timer.
 
but if the UAC includes a Proxy-Require header with value as "timer", in
the initial INVITE then the server MUST support "session-timer" in order
to process the request.
 
But again as per RFC Require and Proxy-Require headers are not
recommended to be used - but a UAC needs to include "Session-Expires"
header field to indicate to the server to apply Session Timer.

Regards 
Ranjit 

________________________________

From: [email-masked] [mailto:[email-masked]] On
Behalf Of Prakash Ganesan
Sent: Friday, March 13, 2009 5:08 PM
To: [email-masked]; [email-masked]
Subject: [Sipping] Pls clarify on session timer

Hi All,
I am facing a problem with the session timer.
 
The refesh re-invite contains header field Require: timer and my server
is rejecting the request with 420 bad extension. When I remove the
header field Reqire: timer, it is working fine. 
I am bit confused with the section 7.1 Generating an Initial Session
Refresh Request, in RFC 4028 it is referring to the first SIP invite or
the first session refresher (re-Invite)

-- 
Cheers
Prakash