With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cmGroupIndex
cm Group Index
1.3.6.1.4.1.9.9.47.1.2.1.1.1
This object identifies the group containing the modems for which this entry contains information.
Back to CISCO-MODEM-MGMT-MIB MIB page.
IPHost Network monitor allows you to monitor cmGroupIndex on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco optical switches right now.