A “Captive Portal” is a web-page that a user must view and interact with before being given access to a Wi-Fi network.
“Captive Portal” is mainly used for authentication purposes and is usually used with free Wi-Fi “hot spots” such as those in business centres, airports, hotel lounges and coffee shops etc.
Our Application Note on Captive Portals discusses Captive Portal and how to implement on our Routers. click here