With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
isdnLapdPeerSabme
isdn Lapd Peer Sabme
1.3.6.1.2.1.10.20.1.3.4.1.3
The number of peer SABME frames received on this interface. This is the number of peer-initiated new connections on this interface.
Back to ISDN-MIB MIB page.
IPHost Network monitor allows you to monitor isdnLapdPeerSabme 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.