What is the function of a captive portal in network security?

A captive portal serves a specific function in network security by requiring users to authenticate before they are granted access to the network. When a device connects to a network that uses a captive portal, the user is typically redirected to a web page where they must enter credentials, agree to terms of service, or perform some other verification. This process ensures that only authorized users can access the network and can help prevent unauthorized access, protect sensitive data, and manage user activity on the network.

For instance, captive portals are often used in public Wi-Fi networks to ensure that individuals using the network agree to certain usage policies or display advertisements before they can gain full access. This mechanism not only enhances security but also allows network administrators to control who is using their network and under what conditions.