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New Member

VoIP with PRI between Nortel Option 61 and Avaya Definity

I want to do 4 digit dial between several Option 61's and Avaya Definity's. My plan was to connect the PBX's to the Cisco router using NM-HDV-1T1's (3600 based Frame relay network). I wanted to implement PRI between the PBX and the Cisco router at the Nortel site and the Definity site to achieve calling station ID end-to-end. Someone told me that because Nortel and Avaya speak PRI "differently" (and therefore incompatible) that we would have to use T1 CAS instead. The downside here would be that we would lose calling station ID capability (we would only be able to do calling trunk ID then I believe). I thought that the NM-HDV's would be able to handle PRI compatibility since the NM-HDV's are converting the signal to IP. Can anyone shed some light on this type of config?


New Member

Re: VoIP with PRI between Nortel Option 61 and Avaya Definity

I could be wrong, but I think you are confusing the two technologies. Look at it from this perspective. Avaya using DCS trunks to connect to other Avaya switches and pass caller-id and other call information with its own proprietary solution. Using VoIP to transport this signaling is not fix for the incompatibility. It is simple a transport method.

We use transparent ccs to connect two Avaya switches across our frame relay network currently which is much cheaper than the point to point T1 that was required previously.

New Member

Re: VoIP with PRI between Nortel Option 61 and Avaya Definity

Caller-ID has always been a sticky issue when it comes to PRI and Cisco routers. The issue is with what portion of the QSIG standards does the Cisco router(s) and the Avaya/Nortel PBX's adhere to. Software version and hardware incompatibility has been a problem with this.. Also, the fact that Avaya and Nortel handles some signalling via proprietary protocols does not help.

What I've been able to gather is is that if you were wanting to off-load your PBXs to an IP backbone, then it is best to do it via the Avaya or Nortel IP-Trunk cards and H.323.