With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cdxCmCpeCmStatusIndex
Cisco DOCSIS Cable Modem Cpe Cable Modem Status Index
1.3.6.1.4.1.9.9.116.1.3.1.1.6
Pointer to an entry in docsIfCmtsCmStatusTable identifying status of the CM (which the CPE connects to.)
Back to CISCO-DOCS-EXT-MIB MIB page.
IPHost Network monitor allows you to monitor cdxCmCpeCmStatusIndex 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.