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 ??

Pl Reply

  • By definition, you won't be able to query an unmanaged switch for information like port status.
    – Ron Maupin
    Oct 9, 2015 at 13:57
  • Did any answer help you? if so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you could provide and accept your own answer.
    – Ron Maupin
    Aug 12, 2017 at 19:21

2 Answers 2


There's no special way to see if you're connected to "The Internet" since it is just a collection of inter-networks. (as far as I'm aware)

Most methods just ping a server that is known to be on the internet, such as Google or an ISP server. The server you pick should be reliable, since connections (such as those between countries) go down from time to time.

Also I personally try to pick a server that isn't likely to be filtered or redirected by a network, as that could trick the result. For example the network might redirect any packets meant for Google or Facebook to an internal "You are not allowed" page. This will still give a positive ping result though.


As far as I understood your question you want to develop a device which is being placed between an internet uplink and an unmanaged switch and want to determine if the internet connectivity is being given or not. h.

You want to determine if a link is UP or DOWN. The problem is that you connect from the switch to your ISP that in return connects to other ISPs. You would only determine the state of the direct connection from the switch to the first active networking device within the ISPs network but not the end-to-end connectivity.

As NetMan pointed out it would be more reasonable to check the connectivity end-to-end because a low level check like interface UP/DOWN does not indicate if the connectivity is really given.

For example one could setup a script to ping a well known ip address that should be reachable at any given time.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.