Wireless networks can be vulnerable to a malicious outsider gaining access because of the default settings on some wireless hardware, the accessibility that wireless networks offer, and present encryption methods.
The concepts that are presented in his article are general suggestions, and may help make your wireless network more difficult for a malicious outsider to gain access. For more specific information about the implementation of these suggestions, see the documentation for your wireless network hardware or contact the hardware vendor.
The 802.11b standard permits Wired Equivalent Privacy (WEP) encryption. Depending on the manufacturer and the model of the network adapter and access point, there are two levels of WEP typically available: 64-bit encryption based on a 40-bit encryption key, and a 24-bit initialization vector, and 128-bit encryption based on a 104-bit key and a 24-bit initialization vector. In addition to enabling WEP, there are other steps that you can take to make your home local area network (LAN) more secure.
For more details, please see:
http://support.microsoft.com/kb/309369
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