With IPHost Network Monitor you can run simple snmp requests against a D-Link device in your network.
swPimRPSetTable
Switch Pim RP Set Table
1.3.6.1.4.1.171.12.52.3.8.2
The (conceptual) table listing PIM information for candidate Rendezvous Points (CRPs) for IP multicast groups. When the local router is the BSR, this information is obtained from received Candidate-RP-Advertisements. When the local router is not the BSR, this information is obtained from received RP-Set messages.
Back to PIM-SM-MIB MIB page.
IPHost Network monitor allows you to monitor swPimRPSetTable 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 access points right now.