User Manual for the NETGEAR 54 Mbps Wireless USB 2.0 Adapter WG121

802.11 Authentication

The 802.11 standard defines several services that govern how two 802.11 devices communicate. The following events must occur before an 802.11 Station can communicate with an Ethernet network through an access point such as the one built in to the WG121:

1.Turn on the wireless station.

2.The station listens for messages from any access points that are in range.

3.The station finds a message from an access point that has a matching SSID.

4.The station sends an authentication request to the access point.

5.The access point authenticates the station.

6.The station sends an association request to the access point.

7.The access point associates with the station.

8.The station can now communicate with the Ethernet network through the access point.

An access point must authenticate a station before the station can associate with the access point or communicate with the network. The IEEE 802.11 standard defines two types of authentication: Open System and Shared Key.

Open System Authentication allows any device to join the network, assuming that the device SSID matches the access point SSID. Alternatively, the device can use the “Any” SSID option (case sensitive) to associate with any available Access Point within range, regardless of its SSID.

Shared Key Authentication requires that the station and the access point have the same WEP Key to authenticate. These two authentication procedures are described below.

Open System Authentication

The following steps occur when two devices use Open System Authentication:

1.The station sends an authentication request to the access point.

2.The access point authenticates the station.

3.The station associates with the access point and joins the network.

This process is illustrated in below.

Wireless Networking Basics

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NETGEAR WG121 user manual Open System Authentication