With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
mgEndpointExtTable
mg Endpoint Ext Table
1.3.6.1.4.1.351.150.10.1.3.3
This table extends the mgEndpointTable. Objects that do not directly describe the endpoint but extend the rules to configure the mgEndpointTable can be added to this table. Each table entry describes an instance of an endpoint on a media gateway.
Back to CISCO-WAN-MG-MIB MIB page.
IPHost Network monitor allows you to monitor mgEndpointExtTable 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.