ZyXEL G-170S User’s Guide

2.2.5 WPA(2) with RADIUS Application Example

You need the IP address of the RADIUS server, its port number (default is 1812), and the RADIUS shared secret. A WPA(2)-RADIUS application example with an external RADIUS server looks as follows. "A" is the RADIUS server. "DS" is the distribution system.

1The AP passes the wireless client's authentication request to the RADIUS server.

2The RADIUS server then checks the user's identification against its database and grants or denies network access accordingly.

3The RADIUS server distributes a Pairwise Master Key (PMK) key to the AP that then sets up a key hierarchy and management system, using the pair-wise key to dynamically generate unique data encryption keys to encrypt every data packet that is wirelessly communicated between the AP and the wireless clients.

Figure 11 WPA(2) with RADIUS Application Example

2.3 Authentication Type

The IEEE 802.11b/g standard describes a simple authentication method between the wireless stations and AP. Three authentication types are defined: Auto Switch, an Open system mode and a Shared key mode.

•Open system mode is implemented for ease-of-use and when security is not an issue. The wireless station and the AP do not share a secret key. Thus the wireless stations can associate with any AP and listen to any data transmitted plaintext.

•Shared key mode involves a shared secret key to authenticate the wireless station to the AP. This requires you to enable the wireless LAN security and use same settings on both the wireless station and the AP.

•Auto Switch authentication mode allows the G-170S to switch between the open system and shared key modes automatically. Use the auto mode if you do not know the authentication mode of the other wireless stations.

Chapter 2 Wireless LAN Network

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