Dictionary · Protocols and Ports
RADIUS
RADIUS — Remote Authentication Dial-In User Service
Identity · Intermediate
A protocol that lets a network device ask a central server to authenticate a user and record accounting data. Authentication commonly uses UDP 1812, and accounting uses UDP 1813.
A wireless controller or VPN gateway does not need a separate password list. It asks a central server whether the user may join, then can report when the session starts and stops.
Example: An access point forwards a person's login to a central server, which checks the directory and returns accept or reject.
Ports
- UDP 1812 — Authentication
- UDP 1813 — Accounting
Common misconception
- The server decides the authentication result. The access point is the client of that server, which is the reverse of everyday client language.