With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cnatAddrBindTable
cnat Address Bind Table
1.3.6.1.4.1.9.10.77.1.2.2
This table holds information about the currently active NAT BINDs.
Back to CISCO-IETF-NAT-MIB MIB page.
IPHost Network monitor allows you to monitor cnatAddrBindTable 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.