With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
diffServQNextFree
Services Differentiated Services Services Q Next Free
1.3.6.1.2.1.97.1.7.1
This object contains an unused value for diffServQId, or a zero to indicate that none exist.
Back to DIFFSERV-MIB MIB page.
IPHost Network monitor allows you to monitor diffServQNextFree on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco wireless switches right now.