Network link

Occasionally,I get the message : the network link is down or has be come discontinuous.The code of the  event is1002.Why I get this message.What is a router problem and what can I do to identify the receipt of this message ?

Configuration : Windows8.

It means exactly what it says.   Your network link is not reliable.   Check the cables and the system into which it’s plugged.  

If it’s plugged into your router directly, does your router stay powered on 24x7?  If not, then that’s the reason.