With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
csbCurrPeriodicStatsCongestionFailure
Cisco Session Border Curr Periodic Stats Congestion Failure
1.3.6.1.4.1.9.9.657.1.3.1.12
This object indicates the number of call setup failures due to congestion during this interval.
Back to CISCO-SESS-BORDER-CTRLR-CALL-STATS-MIB MIB page.
IPHost Network monitor allows you to monitor csbCurrPeriodicStatsCongestionFailure 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.