Dummies, Wireless

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Part III: Installing a Wireless Network
No network security system is absolutely secure and foolproof. And, as we
discuss in this chapter, Wi-Fi networks have some inherent flaws in their
security systems, which means that even if you fully implement the security
system in Wi-Fi (WPA or especially WEP), a determined individual could still
get into your network. We’re not trying to scare you off here. In a typical residential
setting, chances are good that your network won’t be subjected to
some sort of determined attacker like this. Follow our tips, and you should be
just fine.
Assessing the Risks
The biggest advantage of wireless networks — the fact that you can connect
to the network just about anywhere within range of the base station (up to
300 feet, or even longer with the new 802.11n technology) — is also the
biggest potential liability. Because the signal is carried over the air via radio
waves, anyone else within range can pick up your network’s signals, too. It’s
sort of like putting an extra RJ-45 jack for a wired LAN out on the sidewalk in
front of your house: You’re no longer in control of who can access it.
One thing to keep in mind is that the bad guys who are trying to get into your
network probably have bigger antennas than you do. Although you may not
pick up a usable signal beyond a few hundred feet with that PC Card with a
built-in antenna in your laptop PC, someone with a big directional antenna
that has much more gain than your PC’s antenna (gain is a measure of a circuit’s
ability to increase the power of a signal) may be able to pick up your
signals — you would never know it was happening.
General Internet security
Before we get into the security of your wireless LAN, we need to talk for a
moment about Internet security in general. Regardless of what type of LAN
you have — wireless or wired or using powerlines or phone lines or even
none — when you connect a computer to the Internet, some security risks
are involved. Malicious crackers (the bad guys of the hacker community) can
use all sorts of tools and techniques to get into your computers and wreak
havoc.
For example, someone with malicious intent could get into your computer
and steal personal files (such as your bank statements you’ve downloaded by
using Quicken) or mess with your computer’s settings — or even erase your
hard drive. Your computer can even be hijacked (without your knowing it)
as a jumping off point for other people’s nefarious deeds; as a source of an