I have a customer that currently has primarily Nortel PABX's connected to the PSTN via primary rate interfaces. On this PABX they have a large number of alarms being monitored, connected to analog interfaces on the Nortel.
I'm currently working on a project to install a number of Cisco 2900 series ISR's that will sit in between the PSTN and PABX's - I will configure the PRI on the Cisco gateway to emulate a network PRI and connect the Nortel into this, instead of directly into the PSTN, as shown below
PSTN PRI <----------------> Cisco ISR <------------> Nortel PRI
I'm don't have a lot of experience with alarm systems and I understand that they use a variation on DMTF codes - has anyone passed alarm signals through a Cisco gateway? Am I likely to encounter any problems?
This will be ISDN in and out so no IP transcoding will be happening
PS: We have implemented a Cisco Communications Server cluster, currently routing the calls through the Nortel. This will allow us to take the Nortel out of the path and help migrating users.
The next project will involve removing the Nortel entirely and the alarms will need to go via VG224's or ATA's - I've searched the discussions and see that managing alarms can cause a few headaches via IP - any suggestions welcome
Thanks in advance