Remote Authentication Dial-In User Service (RADIUS)

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Remote Authentication Dial-In User Service (RADIUS) is a AAA protocol used to manage remote and wireless authentication infrastructures.

• widely used for client device access over VPN
• wireless access point is configured as a client of the RADIUS server
  • WAP forwards credentials between the RADIUS server and the supplicant without being able to read it
• each RADIUS client must be configured with:
  • IP address of the RADIUS server
  • same shared secret
    • enables trust
• often used for network access control over end user devices
• allows the authenticator and authentication server to communicate authentication and authorization decisions
  • authenticator is a RADIUS client
  • authentication server is a RADIUS server
• several RADIUS server and client products
• uses UDP ports 1812 and 1813