With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cvpdnSessionAttrCallDuration
cvpdn Session Attr Call Duration
1.3.6.1.4.1.9.10.24.1.3.2.1.4
This object specifies the call duration of the current active session.
Back to CISCO-VPDN-MGMT-MIB MIB page.
IPHost Network monitor allows you to monitor cvpdnSessionAttrCallDuration 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.