With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cProxyCallHistoryTxAudioBytes
Cisco Proxy Call History Tx Audio Bytes
1.3.6.1.4.1.9.10.57.1.2.1.1.18
The number of audio bytes transmitted to the remote end for this call.
Back to CISCO-PROXY-CONTROL-MIB MIB page.
IPHost Network monitor allows you to monitor cProxyCallHistoryTxAudioBytes on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco firewalls right now.