[Asterisk-Users] Astersk as AVAYA IVR

[Matt]

I'm thinking about using asterisk as an IVR system with an existing avaya index system.  

I've got 2x PRI 30 lines coming in to the Index, and I have 4 spare PRI cards in the Index.  I was thinking about using a QUAD PRI card from Digium and having the calls come into the Index then transfer to Asterisk for IVR then back to the Index.   That way if we get 60 inbound calls we'd in essence be using all 6 PRI cards in the Index.  (2 for termination to PSTN, 2 for outbound calls from Index to Asterisk and 2 for calls back from Asterisk to Index).

Is this feasible?  Can anyone offer some tips/advice based on their experience?  I've had a look around and I can't find anything relating to tromboning or anti-tromboning so I suppose each call will have to take the path of:

PSTN
|
Index
|
Asterisk
|
Index
|
Agent


Regards

Matt