[Asterisk-Users] RE: Shared line appearances

[David Gomillion]

> "Paul Rodan" wrote:
> 
> I don't think the nature of these phones would allow for such 
> a thing. It was designed for transfers and such, to be a real 
> PBX, not like having 4 phone lines from BellSouth and 
> multiple 4 line phones.

According to the admin manual, the phone supports "shared call
appearances (SCA) using the SUBSCRIBE-NOTIFY method in the 'SIP Specific
Event Notification' framework (RFC 3265).  The events used are: -
'call-info' for call appearance state notification - 'line-seize' for
the phone to ask to seive the line" (Polycom Administrator manual,
version 1.3.0, page 135)

The trick is that we don't offer shared lines, per se, but shared
extensions.  So, if there are 2 phones in the same office, they can
share the same 2 extensions, allowing transfers without transferring, if
that makes any sense.  Only one party can have the call at a time, but
any phone can see the status, and seize the line if the call is on hold
or ringing.

> 
> I couldn't imagine SER/Asterisk/any SIP proxy or program 
> doing what is needed.
>

This behavior is available from Cisco's Call Manager.
 
> 
> The only idea I had to get asterisk to do it would be have 
> the calling party thrown into a conference room right away, 
> and then have it ring all the other phones. Whoever answers 
> it would then be put into the conference room with the 
> calling party.  But I think the trick is, whenever a person 
> calls in, they get thrown put into a conference room, and 
> then the PolyCom's all have to auto-answer and place the 
> calls on silent hold, so that everybody is thrown into the 
> conference room. That shouldn't be TOO hard to rig, but how 
> do you get all the phones to ring as well until somebody 
> picks up, so that there is at least 1 active person in the 
> conference with the calling party. Then any other phone 
> should be able to bust in simply by taking that line off of hold. 
> 

That might work, but there has to be a more elegant solution.

>  
> 
> Good luck with that :-)
> 
>