With IPHost Network Monitor you can run simple snmp requests against a Nortel device in your network.
vrPpTbpIndex
Virtual Router Passport Tbp Index
This variable represents the index for the vrPpTbp tables.
Back to Nortel-Magellan-Passport-BridgeMIB MIB page.
IPHost Network monitor allows you to monitor vrPpTbpIndex 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 modems right now.