With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
ctcConnectionClientPort
Cisco Transaction Connection Connection Client Port
1.3.6.1.4.1.9.9.144.1.5.1.6
Port number used on client machine for this connection.
Back to CISCO-TRANSACTION-CONNECTION-MIB MIB page.
IPHost Network monitor allows you to monitor ctcConnectionClientPort 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.