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Windows: Network Connectivity Status Indicator (NCSI) will ping www.msftncsi.com on older versions (8.1 and lower) or www.msftconnecttest.com on newer versions
by zinekeller 6y ago
Windows: Network Connectivity Status Indicator (NCSI) will ping www.msftncsi.com on older versions (8.1 and lower) or www.msftconnecttest.com on newer versions (10), and then prompts to open the web browser. Since IE/Edge will be always there, it works.
macOS: same as iOS (a dedicated window pinging www.apple.com).
Firefox: Detects detectportal.firefox.com and asks the user if the want to access the captive portal.
Android: Detects connectivitycheck.android.com on Android 5 and connectivitycheck.gstatic.com on Android 6+. I don't know if it applies to all phones, but I'm sure (that except for phones on Android One or Nexus/Pixel) Samsung also does this for phones outside of China.