With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
ccmSIPDeviceInfoGroup
Cisco Call Manager SIP Device Info Group
1.3.6.1.4.1.9.9.156.3.2.23
A collection of objects which provide info about all SIP devices within the scope of the local CallManager. It comprises of the SIP Device table.
Back to CISCO-CCM-MIB MIB page.
IPHost Network monitor allows you to monitor ccmSIPDeviceInfoGroup on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco switches right now.