With IPHost Network Monitor you can run simple snmp requests against a D-Link device in your network.
swPortSecPortMaxLernAddr
Switch Port Sec Port Max Lern Address
1.3.6.1.4.1.171.12.63.3.1.1.1.2
Indicates the allowable number of addresses to be learned on this port. The max entry range is (0..N). The value N means the max number and is determined by the project itself.
Back to PORT-SECURITY-MIB MIB page.
IPHost Network monitor allows you to monitor swPortSecPortMaxLernAddr 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.