With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cvVoIPCallHistoryRemMediaPort
Cisco Voice Vo IP Call History Remote Media Port
1.3.6.1.4.1.9.9.63.1.4.2.1.29
Remote media end point listener port to which to transmit voice packets.
Back to CISCO-VOICE-DIAL-CONTROL-MIB MIB page.
IPHost Network monitor allows you to monitor cvVoIPCallHistoryRemMediaPort 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.