ZyXEL Communications 5 Series - Manual (Page 200)

ZyWALL 5/35/70 Series User’s Guide
200 Chapter 10 Wireless LAN
10.9 802.1x Overview
The IEEE 802.1x standard outlines enhanced security methods for both the authentication of
wireless stations and encryption key management. Authentication can be done using the local
user database internal to the ZyWALL (authenticate up to 32 users) or an external RADIUS
server for an unlimited number of users.
10.9.1 Introduction to RADIUS
A RADIUS (Remote Authentication Dial In User Service) server enables user authentication,
authorization and accounting. RADIUS is based on a client-sever model that supports
authentication and accounting, where access point is the client and the server is the RADIUS
server. The RADIUS server handles the following tasks among others:
• Authentication
Determines the identity of the users.
• Accounting
Keeps track of the client’s network activity.
RADIUS user is a simple package exchange in which your ZyWALL acts as a message relay
between the wireless station and the network RADIUS server. See RFC 2138 and RFC 2139
for more on RADIUS.
10.9.1.1 Types of RADIUS Messages
The following types of RADIUS messages are exchanged between the access point and the
RADIUS server for user authentication:
• Access-Request
Sent by an access point requesting authentication.
• Access-Reject
Sent by a RADIUS server rejecting access.
• Access-Accept
Sent by a RADIUS server allowing access.
• Access-Challenge
Sent by a RADIUS server requesting more information in order to allow access. The
access point sends a proper response from the user and then sends another Access-
Request message.
The following types of RADIUS messages are exchanged between the access point and the
RADIUS server for user accounting:
• Accounting-Request