With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
rprClientCurrentOutMcastClassBEirFrames
rpr Client Current Out Mcast Class B Eir Frames
1.0.8802.17.1.1.1.4.1.1.30
The number of client to MAC classB EIR multicast and broadcast frames in the current interval.
Back to IEEE-802DOT17-RPR-MIB MIB page.
IPHost Network monitor allows you to monitor rprClientCurrentOutMcastClassBEirFrames on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco multiplexers right now.