With IPHost Network Monitor you can run simple snmp requests against a Nortel device in your network.
apsSdOnLines
aps Sd On Lines
This attribute indicates which lines (if any) are currently experiencing a Signal Degrade (SD). Description of bits: protection(0) working(1)
Back to Nortel-Magellan-Passport-ApsMIB MIB page.
IPHost Network monitor allows you to monitor apsSdOnLines 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.