Radius Glossary

Throughout this document the following terms are used:

RADIUS: (All capitals) The Remote Authentication in Dial-In User Service protocol as described in RFC 2138, 2865 and 2866.
NAS: NAS stands for Network Access Server. It is a computer or a special device designed to provide access to the network. For example, it can be a computer connected to the network and equipped with several modems. Such NAS would allow the user connecting to one of its modems to access the network.
Service: A service, such as PPP, SLIP, telnet, etc., provided to a user by the NAS.
Session: Every single instance of a service. Session starts when the service was first provided and ends when the service is ended. A user may have multiple sessions active simultaneously if he is allowed to.
Session ID: Session Identifier. A string of characters uniquely identifying the session.
A/V pair: Stands for Attribute-Value pair section Attributes.
Dial-In or Dial-Up user: A user connecting to a service through the modem line.
User Database: A database in which Radius server keeps information about users, their authentication information, etc.
User's Profile: A record in the User Database describing a particular user. User's Profile keeps the authentication and authorization information for that user, i.e. it contains data describing how this user should be authenticated as well as which services he is allowed to be provided and parameters of these services.