With IPHost Network Monitor you can run simple snmp requests against a D-Link device in your network.
swMcastFilterVLANCurrentCount
Switch Mcast Filter VLAN Current Count
1.3.6.1.4.1.171.12.53.8.1.3
This object indicates the counter of registered groups within this VLAN.
Back to MCAST-FILTER-MIB MIB page.
IPHost Network monitor allows you to monitor swMcastFilterVLANCurrentCount on D-Link device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring D-Link switches right now.