With IPHost Network Monitor you can run simple snmp requests against a D-Link device in your network.
swL2IGMPPortMap
Switch L2 IGMP Port Map
1.3.6.1.4.1.171.11.70.5.2.11.5.1.4
This object indicates which ports belong to the same multicast group, on a per-VLAN basis. Each multicast group has an octet string which is indicated by a port map. The most significant bit represents the lowest numbered port, and the least significant bit represents the highest numbered port. Thus, each port of the switch is represented by a single bit within the value of this object. If that bit has a value of '1' then that port is included in the set of ports; the port is not included if its bit has a value of '0'(Note that the setting of the bits corresponding to the port from which a frame is received is irrelevant). The 4 octets represent one unit port according to its logical port. If the unit is less than 32 ports, other ports are not affected and are replaced with zeroes.
Back to DES3552-L2MGMT-MIB MIB page.
IPHost Network monitor allows you to monitor swL2IGMPPortMap 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 routers right now.