With IPHost Network Monitor you can run simple snmp requests against a Nortel device in your network.
sigChanEIsdnActiveVoiceChannels
sig Chan E Isdn Active Voice Channels
1.3.6.1.4.1.562.2.4.1.115.14.16.1.2
This attribute indicates the number of channels that are currently used by voice calls. This includes modem calls.
Back to Nortel-Magellan-Passport-VnetEuroIsdnMIB MIB page.
IPHost Network monitor allows you to monitor sigChanEIsdnActiveVoiceChannels on Allied Telesis device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Nortel switches right now.