Thread: Detect if a computer is behind a lan or Directly connected to the internet

Does anyone know to detect if a computer is directly connected to the internet or that its using a router etc, gotta be with code to

I'm not going to say absolutely no, because likely there is some protocol by which you could at least indirectly infer that (since your ISP can communicate with your router from outside, and I guess where there's a router, there's a LAN). Investigating this might be your best bet; while you will certainly run afoul of some authority by breaking into a remote router, there may be a legitimate means of querying to see if a router is there and if it can respond to such and such a protocol.

Outside of that, tcp/ip packet headers contain both the IP address (that of the router) and the computer specific MAC address (which allows the router to route correctly). Of course, this alone is indistinguishable from a lone computer...

You're ALWAYS connected to a router. What exactly do you mean by "directly connected?"