Subject: Re: [Sipping] Service Identification in SIP - Routing decissions based on Require/P-R

From: Adam Roach <[email-masked]>
Date: Tue, 13 Mar 2007 23:11:39 -0500

Christer Holmberg (JO/LMF) wrote:
> Hi Jonathan, 
>
>   
>> If you've got a situration where a SIP call *cannot be processed*
>>     
> without 
>   
>> going through application servers, then this is not something 
>> that is signaled with Accept-Contact. Its signaled with 
>> Require or Proxy-Require as appropriate.
>>     
>
> Just for my clarification, where is it said that Require and
> Proxy-Require are used, or at least more appropriate, for routing?

My understanding is that it's not really for routing.

The idea behind this whole service identification brouhaha, as far as I 
can tell, is to ensure that calls that may or may not work, albeit in a 
potentially degraded fashion under certain circumstances, just won't 
work at all.

The concept appears to be predicated on the belief that it's better for 
people to completely fail to communicate instead of merely communicating 
in a fashion that they didn't specifically request.

There appears to be a difference in philosophy here regarding whether we 
should be building robust networks and endpoints that can recover from 
suboptimal conditions or extraordinarily fragile ones that intentionally 
break things.

/a

_______________________________________________
Sipping mailing list  https://www1.ietf.org/mailman/listinfo/sipping
This list is for NEW development of the application of SIP
Use [email-masked] for questions on current sip
Use [email-masked] for new developments of core SIP