windows - How does my computer know that it is connected to the Internet? -


sorry asking such mundane question, i'm curious. if open network connections dialog on windows machine, shows me cute little picture of computer connecting router , globe (labeled internet). windows trying connect in order decide computer has internet connectivity? assume there no ip4 address 'the internet', going? sending ping address @ microsoft home office? if address disappear, window's machine decide no longer has route internet? windows boxes 'close' address incorrectly report internet when couldn't.

i'll stop before gets silly. seriously, criteria windows box use determine has internet connectivity? i'm assuming linux , ios systems have equivalent feature. use same criteria?

the general ip address used 'the internet' 8.8.8.8 - or google.com.

if can ping it, , web page it, there's pretty chance can @ least some of internet.

but windows - network connectivity status indicator - uses different domain: dns.msftncsi.com

it (unless disabled gpo):

  • resolve name, , verify has 'right' ip (131.107.255.255 fd3e:4f5a:5b81::1 )
  • perform http address , check gets result. ncsi

presumably if different responses retrieved, can tell if has wi-fi login or similar.


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