If you have a home network router, your computer and other computers
on the network (such as your spouse’s laptop and your children’s
computer) are protected from the outside world.
However, you are not protected from the computers inside the router.
So you might want to leave on the Windows Firewall or a two-way
firewall such as ZoneAlarm on your computer. Here’s why:
Maybe your children or roommates have their own computers and they regularly infect it with spyware or viruses.
A friend or family member sometimes comes over with an infected laptop and connects it to your home network.
You leave your wireless network unsecured and a wireless network
snoop connects and exposes your computers on the network to viruses,
spyware, or their own curiosity, “Wireless Network Snoops: Lock Down
Your Wi-Fi Network,”
Install a Hardware Firewall
For sheer firewall simplicity, I recommend installing a home network
router with built-in network address translation (NAT) firewall
capabilities.
Some things to keep in mind when it comes to a NAT firewall are
* It does not use any memory on your computer, so the firewall is invisible.
* It works silently to defend your network. You’ll never see pop-ups, alerts, or other annoyances.
* It stops inbound threats but won’t stop outbound nasties that might be on your computer.
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If you would like to check your firewall’s defenses, check out Steve
Gibson’s free firewall test called ShieldsUP! It’s an excellent and
well-documented online test available at [You must be registered and logged in to see this link.] that runs
tests against your computer or home network and explains in careful
detail where you are vulnerable.
To take advantage of a NAT firewall, you need to buy an
Internet-sharing device called a home network router from any one of
several well-known vendors, including
* D-Link—[You must be registered and logged in to see this link.]
* Netgear—[You must be registered and logged in to see this link.]
* Linksys—[You must be registered and logged in to see this link.]
* Belkin—[You must be registered and logged in to see this link.]
* SMC—[You must be registered and logged in to see this link.]
* Apple—[You must be registered and logged in to see this link.]

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If you choose a wireless connection, most new laptops have built-in
capabilities for this. You can, however, buy wireless adapter cards for
both a PC and laptop without built-in wireless.
These routers will cost you about $60 or less (unless you choose
Apple’s Airport Extreme and then you’re in for $200). A router connects
to your high-speed Internet modem from either your cable TV or
telephone company and shares that connection with several computers in
your home. Your computer(s) in turn connect to the router via network
cables or using a wireless connection (also known as Wi-Fi).
The router configuration is fairly straightforward. When you set the
device up, there is a walk-through wizard that configures your
computers and the router so they work together. Both Macs and PCs can
co-exist on a router together and even share files with each other.
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If the idea of setting up a router scares the ham out of your
sandwich, you should check out Mark Edward Soper’s excellent book
called Absolute Beginner’s Guide to Home Networking.
When you install the network, you need settings from your Internet
provider to input into the router during setup. To learn about wireless
network snoops and how to configure your router to be secure. After the
router is set up and running and you can connect to the Internet with
your computer(s), there’s nothing further to do. That NAT firewall runs
automatically.