Which additional security component must be configured for WPA2-Enterprise on a WLAN?

WPA2-Enterprise requires a RADIUS server for authentication. Unlike WPA2-Personal, which uses a pre-shared key, WPA2-Enterprise leverages 802.1X to authenticate users or devices against a central database, typically managed by a RADIUS server. The RADIUS server verifies user credentials (e.g., username/password) and then authorizes access to the network. A PKI server is used for certificate management, which can be part of an EAP method used with RADIUS but isn't the primary authentication server itself. NTP servers synchronize time, which is important for security but not directly for WPA2-Enterprise authentication. TACACS+ servers are primarily used for device administration authentication and authorization, not for WLAN client authentication.