Appendix D Wireless LANs

•Authorization

Determines the network services available to authenticated users once they are connected to the network.

•Accounting

Keeps track of the client’s network activity.

RADIUS is a simple package exchange in which your AP acts as a message relay between the wireless client and the network RADIUS server.

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

Sent by the access point requesting accounting.

•Accounting-Response

Sent by the RADIUS server to indicate that it has started or stopped accounting.

In order to ensure network security, the access point and the RADIUS server use a shared secret key, which is a password, they both know. The key is not sent over the network. In addition to the shared key, password information exchanged is also encrypted to protect the network from unauthorized access.

Types of EAP Authentication

This section discusses some popular authentication types: EAP-MD5, EAP-TLS, EAP-TTLS, PEAP and LEAP. Your wireless LAN device may not support all authentication types.

 

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VSG1432-B101 Series User’s Guide