With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
portSecurityExtTable
port Security Ext Table
1.3.6.1.4.1.9.5.1.10.2
entries is determined by the number of ports in the system which support the Security feature and the number of MAC addresses learned/configured to be secured per port.
Back to CISCO-STACK-MIB MIB page.
IPHost Network monitor allows you to monitor portSecurityExtTable 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.