Windows XP Unwired

Chapter 4. Communicating Securely

With no physical boundary, how can wireless networks be secure? Can they be locked down sufficiently to please security-conscious users? Because the initial wireless security standard was fundamentally flawed, the answer is complicated. In this chapter, I explain the security issues inherent in the 802.11 family and the various ways you can secure a wireless network.

Secure Wireless Computing

Before we start discussing the gory details of Wi-Fi LAN security, let me make one thing clear: Wired Equivalent Privacy (WEP), the security protocol used by most 802.11 networks at the time of this writing, is fundamentally flawed. Though I talk about WEP in much more detail later in this chapter, here is a quick rundown of WEP’s flaws:

• All users in a wireless network share the same secret key. (And a secret key is no longer a secret if more than one person knows it.)

• The implementation of WEP makes it very susceptible to attacks by hackers. It is not a matter of whether it can be cracked, but a matter of how soon. The flaws in WEP have been proven both in theory and practice.

Although WEP has its flaws, it’s worth using to discourage unauthorized users from connecting to your access point. If you need stronger security, you have to rely on other techniques to provide it. In the first part of this chapter, I assume that you are connected to a wireless network (with or without WEP), and that you want to securely access the network resources (including something ...