With IPHost Network Monitor you can run simple snmp requests against a Nortel device in your network.
vsrPeakActiveVoiceChannels
VoiceRoute Peak Active Voice Channels
1.3.6.1.4.1.562.2.4.1.117.16.1.7
This attribute indicates the peak number of B-channels that were active carrying voice during the previous polling period.
Back to Nortel-Magellan-Passport-VoiceNetworkingMIB MIB page.
IPHost Network monitor allows you to monitor vsrPeakActiveVoiceChannels 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 speech servers right now.