Just as you would secure your home with locks and a security system, you should also secure your home or small business computers with a firewall and anti-virus, anti-adware, and anti-virus software.
Firewalls, even the most basic ones, offer lots of protection from trespassers and bad guys. Firewalls come in all shapes and sizes, but a determined hacker may still be able to break in. With that in mind, you should configure your system to thwart attacks by making it as difficult as possible for an intruder to get in and access personal data. There are several ways to do this, and the
best one is to enable the firewall that comes with Service Pack 2 for Windows XP or the Firewall that comes with Windows Vista. You can also purchase a third-party hardware or software firewall, although Windows firewalls are pretty secure and is fine for most home users if you have it. If you have an always-on connection, you may already have a hardware-based firewall in the form of an external router.
Business networks require more protection than a home computer because they generally are larger, internal networks and have valuable data that must be protected. Because of this, businesses may use a second type of firewall called a network firewall. Network firewalls can be hardware or software based and can range from fairly inexpensive to extremely expensive. One common large-business firewall is Microsoft’s ISA Server, which watches traffic that enters and leaves the intranet and looks for uninvited or malicious data. Another popular firewall for businesses is the intrusion detection firewall that identifies attack patterns and uses routers to stop the connection to the source before harm can be done. These advanced firewalls offer protection that is far superior to the simple host-based firewalls like the one you get in XP SP2 or Vista. You can get plenty of information about these different firewalls—their capabilities, pricing, and configuration—from your local computer store and from Windows XP and Vista Help files.
Firewalls won’t protect your PCs from a virus, adware, spyware, or worm, so you’ll need extra protection that you can afford. If you have a single home computer that connects directly to the Internet and is not networked, you can probably get by fairly securely and cheaply using Windows XP’s firewall and a good anti-virus software program. If you have an external hardware router, or if your anti-virus software program comes with its own firewall, that may work just fine too. If you have two or three computers on a home network that shares an Internet connection the same is true.
It's also important to have firewalls if you have an always-on connection, although these days virtually all routers come with a very effective hardware firewall. Your local computer store certainly carries at least a few of these software firewall products and a number of routers, and larger computer retailers like CompUSA offer a bewildering selection.