[Asterisk-Users] ChanIsAvail and SIP

[Olle E. Johansson]

B. J. Bomar wrote:

> Hello all.  Has anyone had any success using ChanIsAvail with only SIP 
> channels?  Is there another, better way to check if an extension is busy 
> without dialing it?

Well, SIP devices live their own life and should really handle this signalling
themselves. That's why ChanIsAvail does not really work with SIP channels,
Asterisk does not control what is happening out there in the wild. The SIP
channel is really a compromise from a business PBX point of view, where you
want to know what is happening out there, which lines are occupied etc etc.

I think that you can use incominglimit and outgoinglimit to limit the number of
calls asterisk place to a SIP device and force busy if there's already a call
going on.

Remember that this limits the number of connections to/from Asterisk, not necessarily
the number of calls on the SIP device.

/O