Reference Manual for the 54 Mbps Wireless Travel Router WGR101
D-4
Wireless Networking Basics
February 2005 (202-10034-03)
WEP Wireless Security
The absence of a physical connection between nodes makes the wireless links vulnerable to
eavesdropping and information theft. To provide a certain level of security, the IEEE 802.11
standard has defined two types of authentication methods, Open System and Shared Key. With
Open System authentication, a wireless computer can join any network and receive any messages
that are not encrypted. With Shared Key authentication, only those computers that possess the
correct authentication key can join the network. By default, IEEE 802.11 wireless devices operate
in an Open System network. Recently, Wi-Fi, the Wireless Ethernet Compatibility Alliance
(
http://www.wi-fi.net
) developed the Wi-Fi Protected Access (WPA), a new strongly enhanced
Wi-Fi security. WPA will soon be incorporated into the IEEE 802.11 standard. WEP and WPA are
discussed below.
WEP 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 WGR101:
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 WEP
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 to associate with any available access point within range, regardless of its SSID.
