With IPHost Network Monitor you can run simple snmp requests against a Nortel device in your network.
vrBrTbStpBridgeId
Virtual Router Br Tb Stp Bridge Id
This attribute specifies the identifier value of this bridge, which serves to uniquely represent this bridge in the spanning tree topology. Thus, a bridgeId is unique only in the spanning tree instance the bridge in participating in. If multiple domain spanning trees exist then the same bridgeId can be re-used across these spanning tree instances.
Back to Nortel-Magellan-Passport-BridgeMIB MIB page.
IPHost Network monitor allows you to monitor vrBrTbStpBridgeId 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.