With IPHost Network Monitor you can run simple snmp requests against a Nortel device in your network.
rtgTopControlBytesRx
rtg Top Control Bytes Rx
This attribute shows the total number of topology routing control packet bytes received by this node from other Passport nodes in the network.
Back to Nortel-Magellan-Passport-BaseRoutingMIB MIB page.
IPHost Network monitor allows you to monitor rtgTopControlBytesRx 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.