With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
dlswDirNBCacheMisses
dlsw Dir NB Cache Misses
1.3.6.1.4.1.2011.2.34.4.1.7
The number of times a cache search for a particular NetBIOS name resulted in failure.
Back to DLSW-MIB MIB page.
IPHost Network monitor allows you to monitor dlswDirNBCacheMisses 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.