With IPHost Network Monitor you can run simple snmp requests against a D-Link device in your network.
swSystemBootTime
Switch System Boot Time
1.3.6.1.4.1.171.12.10.10.3
The boot time of the switch is equal to subtract systemUpTime from swSNTPCurrentTime
Back to DLINK-TIME-MIB MIB page.
IPHost Network monitor allows you to monitor swSystemBootTime 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 switches right now.