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I always assumed that Windows assumes that it is on the Internet when there is a default gateway.

Turns out this is not the case!

How does it judge, it is on the Internet? Does it "phone home"?

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Why not use a passive tap (or monitoring port on the switch) and use wireshark to watch what flows in and out of the machine? Seems a lot better than guessing. – John Gardeniers Oct 12 '10 at 3:00
@John Gardeniers, yes - but then I would not give the kind people on serverfault a chance to express themselves on this matter, right? :) – Prof. Falken Oct 12 '10 at 7:59
up vote 11 down vote accepted

As documented at

nslookup followed by HTTP GET

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wget: unable to resolve host address `' Isn't that weird then? – Prof. Falken Oct 11 '10 at 14:57
That is strange, works for me – Chris S Oct 11 '10 at 15:04
Works for me too now. OK, weird, but then DNS always had a touch of black magic over it: – Prof. Falken Oct 12 '10 at 7:57

A simple "ping" could tell if it is online. This is a usual way and there are no privat datas transmitted.

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While that certainly is A way, is it THE way? That's the question the OP is asking. – joeqwerty Oct 11 '10 at 14:42
No, ping tells you if is online and that ICMP traffic is working between you and them. If is down, I'm not necessarily offline... – ceejayoz Dec 8 '11 at 23:12

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