With IPHost Network Monitor you can run simple snmp requests against a Nortel device in your network.
x25DteLcnCallingNetworkFax
x25 Dte Logical Channel Number Calling Network Fax
1.3.6.1.4.1.562.2.4.1.90.4.11.1.23
This attribute indicates the Calling Network facilities which were signalled in the call packet. A value of null (empty string) means no calling network facilities were signalled.
Back to Nortel-Magellan-Passport-X25DteMIB MIB page.
IPHost Network monitor allows you to monitor x25DteLcnCallingNetworkFax 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 multiplexers right now.