My customer is running a Nortel Option 81/81C with release 19 software (single location). We are adding a cisco IPT solution to the mix. Initially, there will be a small number (approx 50) of phones on the Cisco side with the rest (about 700) staying on the Nortel side. Each system has its own voice mail. The PSTN will be connected to the Nortel switch only and a PRI (tie trunks from switch to switch) will connect the cisco and nortel systems. Inbound PSTN calls to the cisco side will therefore come in via T1s/PRIs connected to the Nortel switch and then over the PRI that connects the cisco and nortel switches. It is also expected that Cisco or Nortel users will be able to dial, transfer, or forward calls across the tie-PRI to each other, although because QSIG isnt supported on the Nortel side we know that path replacement (anti-tromboning) will not take place. We would like to have a 4 digit universal dialing plan such that a Cisco or Nortel user could simply dial the 4 digit internal extension and reach the called party, regardless of what switch that phone is connected to. Outbound calls from the cisco side will have to go over the PRI and out the Nortel as well.
The nortel vendor is saying that this will be difficult/impossible to implement because the Nortel switch does not have the coordinated dialing plan (CDP) feature. At the time of release 19 for the Nortel, CDP was optional and the customer didn't choose to get it. Now, since release 19 is old, the nortel vendor is saying that the cdp features can't be added without an exensive upgrade to the latest nortel software.
Im looking to validate what the nortel vendor is saying, i.e. is it correct. Beyond that it would be helpful if I could get a quick outline of my options of how to do this along with any caveats, i.e. features I listed above that would not be supported.
Does anyone have any experience integrating with the older nortel switches?