Captive Portal Check

A captive portal is a login page in public WLAN networks to restrict Internet access to the approval of certain terms of use. When you see a login page on a public network, your device uses a captive portal check. This allows the device to find out whether you have direct Internet access or not. In Android, for example, your device sends a request to a Google server.

More useful links

• Captive Portal Wikipedia
• Source code
• Docker Image