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Re: [reSIProcate] 200 OK for SUBSCRIBE


On Wed, 2005-11-30 at 10:53 -0600, Robert Sparks wrote:
> There's a lot of background that led to this design decision, and the  
> code _is_ doing this on purpose.
> 
> Here's an attempt to capture that background in a nutshell:
> 
> Because proxies can only return one final response to a non-INVITE  
> request, RFC3265 mandates an
> initial NOTIFY to each subscription. If a SUBSCRIBE forks, the  
> NOTIFYs are the only way the subscribing
> client finds out about all the places the subscription was accepted.  
> Further, even in the scenario where
> there is no forking, or even no proxies, the NOTIFY is enough to let  
> you know the subscription has been
> created. So to unify the code, DUM only pays attention to the NOTIFYs  
> for creating subscription usages.
> The 2xx to the SUBSCRIBE itself is ignored (it will always be  
> redundant with the immediate NOTIFY from
> one branch).

And in many cases the NOTIFY will arrive first anyway...

-- 
Scott Lawrence  tel:+1-781-938-5306;ext=162 or sip:slawrence@xxxxxxxxxxx
  Consulting Engineer - Pingtel Corp.  http://www.pingtel.com/
  sipXpbx project coordinator - SIPfoundry  http://www.sipfoundry.org/sipX