With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
diffServMultiFieldClfrSrcAddr
Services Differentiated Services Services Multi Field Clfr Source Address
1.3.6.1.2.1.97.1.2.6.1.5
The IP address to match against the packet's source IP address. This may not be a DNS name, but may be an IPv4 or IPv6 prefix. diffServMultiFieldClfrSrcPrefixLength indicates the number of bits that are relevant.
Back to DIFFSERV-MIB MIB page.
IPHost Network monitor allows you to monitor diffServMultiFieldClfrSrcAddr 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.