[Serusers] presence_b2b UA

[Curt Moore]

Vaclav,

The end goal is to have the SIP phones send a SUBSCRIBE to the SER
server acting as a presence server, which is also acting as a proxy
for presence requests.  The SER presence server will then send a
SUBSCRIBE request to multiple Asterisk servers which are acting as
PAs.

After altering my config, I now have the SIP phones correctly
receiving NOTIFY messages from the presence server based on the
registration state of the watched device.  The next challenge is for
the presence server to generate a SUBSCRIBE out to an Asterisk server
and then be able to relay that status back to the presence server via
a NOTIFY message.  From what you have described, the upcoming
modifications to the PA module may be what is needed.

Once the PA module allows for this behavior, how would I configure SER
so that whenever a SUBSCRIBE is received from a SIP user, the b2b UA
would then generate a SUBSCRIBE out to another SIP entity, such as an
Asterisk server?  Would this be done via a resource list and whenever
a SUBSCRIBE is received for a particular SIP user, the QSA would query
RLS to see if a resource list exists for that particular SIP user and
generate the necessary SUBSCRIBE messages out to all of the SIP
entities on the resource list?

Sorry if I've confused anyone, I'm still trying to understand how all
of the new presence functionality integrates into SER.

Also, great job to Vaclav and all those who have worked on getting
more robust presence support into SER! Thank you all!

-Curt


On 8/10/06, Vaclav Kubart <vaclav.kubart at iptel.org> wrote:
> Hi Curt,
> are presence subscriptions enough? PA module is prepared to generate
> internal (QSA) subscription when it is processing SUBSCRIBE request. But
> it still can not handle responses - this will be done soon. I think that
> this will be what do you need.
>
> I hope that I will have time for it and finish it till the end of
> August.
>
>         Vaclav
>
> On Wed, Aug 09, 2006 at 02:18:07PM -0500, Curt Moore wrote:
> > Hi Vaclav.
> >
> > Thank you for your reply.
> >
> > This sounds very close to what I'm trying to accomplish for presence.
> > I have 1 SER server setup as the main proxy/registrar.  If a SUBSCRIBE
> > message comes into this server, it is forwarded over to a second SER
> > server which maintains the watcher info, a presence server. This
> > currently works perfectly.
> >
> > What I'd like to happen is for the B2B UA on the presence server to
> > generate a new SUBSCRIBE message and send it out to an Asterisk
> > server, essentially having the SER presence server subscribe to the
> > presence of the SIP user on the Asterisk server.  If the presence
> > changes on the Asterisk server, it will send a NOTIFY back to the
> > presence SER server.  This should then, as you mention, trigger a
> > notification through QSA back to any watchers watching this particuar
> > resource.
> >
> > My confusion is how to get the outbound SUBSCRIBE generated through
> > QSA and sent to the Asterisk server from the presence server after the
> > initial inbound SUBSCRIBE comes into the SER presence server.
> >
> > How would I get the SER server to generate the outbound SUBSCRIBE?
> >
> > Thanks!
> > -Curt
> >
> > On 8/9/06, Vaclav Kubart <vaclav.kubart at iptel.org> wrote:
> > >Hi,
> > >presence_b2b processes INTERNAL subscriptions (through QSA - internal
> > >API for status querying) and generates SIP subscriptions according to
> > >them (now only presence subscriptions). Each arriving NOTIFY triggers
> > >notification through QSA.
> > >
> > >It works quite good with one SER as resource list server and another as
> > >presence server.
> > >
> > >        Vaclav
> > >
> > >On Wed, Aug 09, 2006 at 12:01:59PM -0500, Curt Moore wrote:
> > >> Hello all.
> > >>
> > >> I have been experimenting with the ser-0.10.99-xxx branch(es) and have
> > >> a question about the presence_b2b module.
> > >>
> > >> I realize that the module is not yet fully complete but according to
> > >> the documentation, when finished, the module should be able to take an
> > >> inbound SUBSCRIBE request and then create a new SUBSCRIBE request
> > >> outbound to another SIP entity or multiple SIP entities, ie Asterisk
> > >> servers, hence the back to back functionality.  What is the status of
> > >> this functionality?  Is anyone currently working to complete this
> > >> functionality?  I would be interested in helping complete or
> > >> sponsoring the completion of this functionality.
> > >>
> > >> My intent is to have a SER server act as the central watcher database
> > >> server and have all SUBSCRIBE and NOTIFY requests channeled through
> > >> this SER server.  This SER server will then generate new SUBSCRIBE
> > >> requests out to each server in a farm of Asterisk servers and the
> > >> Asterisk servers will then send NOTIFIES back to the SER watcher
> > >> server.  The watcher server will then take care of sending the NOTIFY
> > >> messages to the correct watcher(s), according to the data in its
> > >> watcher database.
> > >>
> > >> Is anyone currently doing anything similar to this using a different
> > >> method or is using the yet to be completed B2B UA the correct/only way
> > >> to accomplish this?
> > >>
> > >> Thanks,
> > >> -Curt
> > >> _______________________________________________
> > >> Serusers mailing list
> > >> Serusers at lists.iptel.org
> > >> http://lists.iptel.org/mailman/listinfo/serusers
> > >
>