To use certificate-based authentication, you need a trusted Certificate Authority (CA) that issues certificates to both the client devices and the RADIUS server.
This can be an external CA (e.g., VeriSign, Let’s Encrypt) or an internal enterprise CA for organizations that want to manage their own certificates.
Steps:
Set up a CA that can issue both client certificates and server certificates.
Ensure that both the client and RADIUS server are configured with certificates signed by the CA.
Issue certificates to users (client devices) that will connect to the Wi-Fi network.
Configure the RADIUS Server to Support EAP-TLS:
The RADIUS server must be configured to use EAP-TLS for authentication.
The server needs a server certificate signed by the CA and must be able to validate client certificates during the authentication process.
Steps:
Install the RADIUS server certificate signed by the CA.
Configure the RADIUS server to authenticate users using EAP-TLS by validating the client's digital certificate.
Configure the RADIUS server to handle certificate revocation lists (CRL) or use Online Certificate Status Protocol (OCSP) to check the status of client certificates.
Example configuration for FreeRADIUS (a popular open-source RADIUS server)
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Configure the Wi-Fi Access Point for WPA2/WPA3-Enterprise:
The Wi-Fi AP must be configured to use WPA2-Enterprise (or WPA3-Enterprise) security mode.
The AP should also be configured to use the RADIUS server for authentication and EAP-TLS as the supported authentication method.
Steps:
Set the Security Mode on the AP to WPA2-Enterprise or WPA3-Enterprise.
Specify the RADIUS server IP address and shared secret on the AP, so that the AP can forward authentication requests to the RADIUS server.