PBX TO PBX TOLLBYPASS

[a.gooding]

good day

ill be as brief as possible

scenario: two pbx systems connected to T1 CAS on 3640 routers. doing toll bypass in that if user dials for outside pstn and then pstn number the call is redirected to remote pbx and does off-net call from there.

that works fine. my question is if the remote site pbx or router becomes unavailable i dont have any fallback to the local side so the call can still go through. im not too sure on how to configure this or if the pbx itself should be able to perform the fallback. from what im seeing once the pbx sends the digits and its matched on one of my dial-peers then the pbx job is done. i may need to have a way to cehck to see if the port is available and then if it is not access the local pstn line in that area.

[dweiner]

You want to investigate Advanced Voice Buy Out (AVBO) or Local Voice Busy Out. AVBO sends what are essentially keep-alives to the remote router/gateway. If the keep-alives don't make it the local T1 port is busied out so the PBX will grab another trunk group. I've tested this where CallManager was acting as the Gatekeeper between multiple PBXs -

On ‘remote’ router with T1 to PBX -

!

call fallback monitor

!

voice-port 1/0:0

busyout monitor probe 10.1.13.254 (Router subnet interface to CallManager subnet)

busyout action graceful

On router near CallManager servers:

rtr responder

Your config will differ b/c you just have the point to point link and no CCM, but this is the feature set you use.

Don