[asterisk-users] Restricting Incoming SIP Calls Without "call-limit"

[Damien Gabrielson]

I have been trying to restrict incoming calls for some time and I have 
not had any luck yet so I hope someone may have done this already.

I receive calls from a SIP provider with whom I do not register. I 
merely accept the call to a certain DID and route the call elsewhere. I 
want to limit the amount of concurrent calls for a certain group of DIDs 
for example:

555-1111, 555-2222, and 555-3333 are all in one group which are allowed 
to have 2 concurrent calls.

I can always add logic to my dial plan to count the calls as they come 
in and hang them up if they are over the limit but I was hoping to find 
a more native way in Asterisk.

Thanks,
Damien