With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cpmCallCount
cpm Call Count
1.3.6.1.4.1.9.10.19.1.1.1.1.7
The number of calls that have occupied this DS0.
Back to CISCO-POP-MGMT-MIB MIB page.
IPHost Network monitor allows you to monitor cpmCallCount on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco multiplexers right now.