Windows Server® 2008 TCP/IP Protocols and Services

Summary

RADIUS messages have a common structure consisting of a fixed-size portion and a variable-size portion. The fixed-size portion contains fields common to all RADIUS messages. The variable-size portion contains RADIUS attributes, which can be standard attributes or VSAs. RADIUS attributes carry data values that are used in authentication, authorization, and accounting of network access. An authentication exchange is one of the following: Access-Request/Access-Accept for a successful authentication and authorization, Access-Request/Access-Reject for an unsuccessful authentication or authorization, or Access-Request/Access-Challenge when the RADIUS server needs more information to evaluate authentication and authorization. An accounting exchange ...