With IPHost Network Monitor you can run simple snmp requests against a D-Link device in your network.
swPimCbsrSubnetMask
Switch Pim Cbsr Subnet Mask
1.3.6.1.4.1.171.12.52.3.1.3.1.3
The IP netmask for this PIM interface.
Back to PIM-SM-MIB MIB page.
IPHost Network monitor allows you to monitor swPimCbsrSubnetMask 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 VPN routers right now.