I wanna design an hardware device (ARM Microcontroller based) to find the availability of internet connection in an ethernet cable. The scenario is, a system connected to a network through an unmanaged network switch, from the switch i want to tap the connection and have to found the internet connection availability (by any LED indications, or..) Note that, the connected system is not accessible to me and the switch must be unmanaged switch that means the network connection is also not accessible and not configurable to the switch. But have to find the internet Link UP/ DOWN connectivity. Is it possible ??