With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cmsStsPortSGs
cms Sts Port S Gs
1.3.6.1.4.1.9.9.721.1.5.1.1.36
This object indicates the number of sources associated with the port identified by the indices
Back to CISCO-MLD-SNOOPING-MIB MIB page.
IPHost Network monitor allows you to monitor cmsStsPortSGs on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco switches right now.