With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cmLineStatusTable
cm Line Status Table
1.3.6.1.4.1.9.9.47.1.3.1
A collection of objects that describe the status of the modem.
Back to CISCO-MODEM-MGMT-MIB MIB page.
IPHost Network monitor allows you to monitor cmLineStatusTable on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco routers right now.
