[sr-dev] default config: do loose_route() for in-dialog NOTIFY as per new RFC 6665

[Iñaki Baz Castillo]

2012/8/17 Juha Heinanen <jh at tutpro.com>:
> regarding this:
>
>> Sure but, how to distinguish the *first* in-dialog NOTIFY and any
>> other later? No way.
>
> i would imagine that presence server does know when subscription is
> created and first notify is sent.

Sure.


> and of course one would use this feature only when sip proxy and
> presence server are both based on kamailio run by the same service
> provider.

So you suggest the presence module to insert a custom header/param in
the first NOTIFY of a subscription just to avoid the intermediary
proxi(es) to do record-routing, but at the same time all the default
script files for SER in sip-router sources call record_route() for
*every* requests (initial and in-dialog). And you really want to avoid
something that both RFC 3265 and 6665 suggest (adding RR for *every*
NOTIFY).

Honestly, I think adding the "feature" you propose is a waste of time
and a not needed complexity. The custom header check could be,
probably, more expensive than just adding RR to every NOTIFY.


> regarding obsoleted rfc, i don't see a big need to support it.  if rr
> missing from notifys would be a big problem, kamailio users would
> already have noticed it.

The problem takes place when a RFC 6665 strict compliant UAC expects
to create the dialog with the Record-Route headers retrieved from the
first NOTIFY. Taking into acount that this requirement appears in RFC
6665 which has been published in July 2012, I expect that no one
existing UAC will suffer it (but maybe new devices do). So Kamailio
users cannot noticed this problem (yet).


Regards.



-- 
Iñaki Baz Castillo
<ibc at aliax.net>