Consider the following before deploying a captive portal:
Take into account the number of wireless clients allowed, services provided, and deployment requirements when considering the benefits and disadvantages of various topologies in the network architecture design.
Captive portal authentication uses secure HTTPS to protect user credentials, but does not typically provide encryption for user data once the user has been authenticated. For private access applications, enable WPA2 (with a strong passphrase) to provide strong encryption.
Assign guest user traffic to a dedicated VLAN, separate from other internal networks.
Include firewall policies in guest access configurations. This ensures that logical separation is provided between guest and internal networks, preventing internal networks and hosts from being reachable through guest devices.
Define guest access services in such a way that end-user traffic does not cause network congestion.
Issue and install a valid certificate on all devices providing captive portal access to the WLAN and wireless network. Ensure the certificate is issued from a public certificate authority, allowing guests to access the captive portal without browser errors.