[Asterisk-Users] Intercom with Cisco SIP 796x phones?

[John Todd]

At 9:59 PM -0500 8/25/03, John Laur wrote:
>
>BTXML support for client applications is necessary to achieve this. The
>SIP images state that they support BTXML; however, they only use it for
>their internal screens and internal navigation. CMXML is the only
>language supported for client applications with the SIP loads currently.
>A little bird at Cisco told me that a future version of the SIP loads
>will support BTXML client applications. (and a less reliable bird told
>me that the next version of call mangler will be SIP-based)

Yes, the same bird has told me similar stories.  However, Cisco is a 
large organization, and there are lots of birds there, some of them 
singing songs that will never be heard by the rest of the world.

Cisco's phones are great (IMHO) and are already full of nice 
features.  However, a few more features in the SIP load would make 
them much more market-able.  Much of this delay has to do with 
internal Cisco politics (despite what they might admit or realize) 
which is somewhat disheartening.

>This will support all of the good stuff I really want to be able to do
>with this phone. For instance, we could forward a URL with the call to a
>BTXML app that causes the phone to display extended information about
>the caller, or the voicemail Services button could show the users a menu
>of their voicemails and choosing one would play the message directly
>over the speaker. Also, intercom would be supported. All this is
>documented in the BTXML guide and ready to go whenever they "open it
>up"..

That would be really useful.

>I suppose it might also be possible to find an "exploit" in the current
>firmware that causes the phone to execute some BTXML from a remote
>location.. we might be able to get in that way, too :)

My idea is to accept SIP NOTIFY messages, password-protected, that do 
certain things.  It's already part of the SIP spec.  An XML URL, as 
an example, would be perfect payload.  As would an INVITE to an 
auto-answer meta-extension (configurable from the phone) for intercom 
or paging.   I've made these suggestions through a feature request 
system within Cisco, and through what hopefully will be a clueful 
channel.  We'll see.

JT