With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
ctcConnectionTable
Cisco Transaction Connection Connection Table
1.3.6.1.4.1.9.9.144.1.5
A table containing connection information. Each row reflects a client connection that is active at this moment.
Back to CISCO-TRANSACTION-CONNECTION-MIB MIB page.
IPHost Network monitor allows you to monitor ctcConnectionTable 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.