With IPHost Network Monitor you can run simple snmp requests against a Nortel device in your network.
appnDnaHgMAvailableChannels
appn Dna Hg M Available Channels
This attribute indicates the number of available channels reported to the hunt group in the Availability Message Packet (AMP). It is incremented by the application when a channel is freed and decremented when a channel is occupied.
Back to Nortel-Magellan-Passport-AppnMIB MIB page.
IPHost Network monitor allows you to monitor appnDnaHgMAvailableChannels 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.