RADIUS (Remote Authentication Dial-In User Service) is a networking protocol providing centralized Authentication, Authorization, and Accounting (AAA) for network access. Operating on a client-server model, a Network Access Server (NAS) acts as the client, forwarding user credentials to a central RADIUS server for verification against a database. Using a shared secret for secure communication, RADIUS employs UDP (or TCP) and attribute-based messages to authenticate users, authorize network access based on predefined policies, and account for network usage, making it a crucial element for securing various network access methods like Wi-Fi (WPA-Enterprise) and VPNs.
WEP (Wired Equivalent Privacy): An older and highly insecure encryption protocol. It doesn't use a RADIUS server.
WEP-Enterprise: This is not a standard or commonly used term. WEP is inherently insecure and not suitable for enterprise use, even with RADIUS.
WPA-Enterprise (Wi-Fi Protected Access Enterprise): This mode uses 802.1X authentication, which requires a RADIUS server to authenticate users with usernames and passwords (or other credentials) before granting them access to the wireless network. This provides much stronger security than WPA-Personal (PSK).
WPS (Wi-Fi Protected Setup): A simplified method for connecting devices to a wireless network, often using a PIN or button press. It's known for security vulnerabilities and doesn't involve a RADIUS server. There is no "WPS-Enterprise" mode