With IPHost Network Monitor you can run simple snmp requests against a Nortel device in your network.
traceSessionX25VcCallReferenceNumber
trace Session X25 Vc Call Reference Number
1.3.6.1.4.1.562.2.4.1.106.3.2.2.11.1.1
This attribute displays the call reference number which is a unique number generated by the switch.The same Call Reference Number is stored in the interval data (accounting record) at both ends of the call. It can be used as one of the attributes in matching duplicate records generated at each end of the call.
Back to Nortel-Magellan-Passport-X25TraceRcvrMIB MIB page.
IPHost Network monitor allows you to monitor traceSessionX25VcCallReferenceNumber 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.