With IPHost Network Monitor you can run simple snmp requests against a D-Link device in your network.
swL3IpFdbInfoIpSubnetMask
Switch L3 Ip Fdb Info Ip Subnet Mask
1.3.6.1.4.1.171.11.70.5.3.2.2.1.1.2
A IP net mask for this interface.for which switch has forwarding and/or filtering information.
Back to SWL3MGMT-MIB MIB page.
IPHost Network monitor allows you to monitor swL3IpFdbInfoIpSubnetMask 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.