asterisk users - Mar 2004 - Routing NOTIFY Messages?

Is it possible to route SIP NOTIFY messages through * ?

Basically, I have an external VoiceMail application that needs the 
ability to send SIP NOTIFY messages to * users, in order to do MWI to 
the SIP phones. I realize the asterisk voicemail application does this, 
but does * have the ability to accept these SIP messages from another 
application. If so, will my application have to REGISTER then INVITE the 
phone then send the NOTIFY message?

Currently, my application can send NOTIFY messages directly to the 
phones in order to turn on and off MWI, but I would really like to be 
able to send these messages to * and have it handle the routing to the 
endpoints as * knows all the endpoints due to registration and proxy 
capabilities. Any input on if and how this can be done would be appreciated.

Thank you. -John

John J. Sawa wrote:
> Is it possible to route SIP NOTIFY messages through * ?
> 
> Basically, I have an external VoiceMail application that needs the 
> ability to send SIP NOTIFY messages to * users, in order to do MWI to 
> the SIP phones. I realize the asterisk voicemail application does this, 
> but does * have the ability to accept these SIP messages from another 
> application. If so, will my application have to REGISTER then INVITE the 
> phone then send the NOTIFY message?
> 
> Currently, my application can send NOTIFY messages directly to the 
> phones in order to turn on and off MWI, but I would really like to be 
> able to send these messages to * and have it handle the routing to the 
> endpoints as * knows all the endpoints due to registration and proxy 
> capabilities. Any input on if and how this can be done would be 
> appreciated.
Incoming NOTIFYs are not handled by Asterisk at all. Asterisk
sends outbound NOTIFY messages for MWI to SIP peers with
mailbox= definition in [peer] section of sip.conf.

The problem with routing incoming NOTIFY is how to handle them, as with
many other SIP non-call things in Asterisk,  Is the user part of
the URI an extension or a SIP peer? It's not obvious.
We can't easily have two name spaces, so today the default handling is
sending a NOTIFY to an extension. SUBSCRIBEs have more or less
the same problem, the implementation today allows SUBSCRIBE to
an Asterisk extension. Many Asterisk admins want to subscribe to
a SIP peer, which breaks the architecture somewhat.

The best solution today is to use a SIP proxy for doing this kind
of stuff.

/Olle

John,

Others have commented already relative to * not routing Notify messages
so I'll pass on that.
> Currently, my application can send NOTIFY messages directly to the 
> phones in order to turn on and off MWI, but I would really like to be 
> able to send these messages to * and have it handle the routing to the 
> endpoints as * knows all the endpoints due to registration and proxy 
> capabilities. Any input on if and how this can be done would be
appreciated.
As a side note, don't expect "both" systems to independently send
the
notify messages to a single phone. One system will turn it on while the
other will turn it off. (Sort of like a previous Snom phone problem when
two extns were defined; a vm message for one extn turned the indicator on
while no vm messages on the second extn turned it back off.)

I don't have a clue whether this would actually impact any other functions,
but one option might be to comment out the vm notify code within * and
let your second vm system send its notify messages directly to the phone.
(I'm likely way off base since I can't read C-code reliably. ;)

Rich