With IPHost Network Monitor you can run simple snmp requests against a Nortel device in your network.
mpanlSigNetworkType
mpanl Sig Network Type
This attribute specifies whether this Frame Relay service is running on a public or a private network. This value is used solely in populating applicable information elements within those Q.933 messages that require a public or private network indication.
Back to Nortel-Magellan-Passport-MpaNetworkLinkMIB MIB page.
IPHost Network monitor allows you to monitor mpanlSigNetworkType 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.