The broadband explosion has provided Internet users with a better, faster solution than the traditional dial-up connections we've been used to over the years. That's the good news. The bad news is, broadband connections have some drawbacks, the most serious of which is the fact that they are "always on."

A connection that never shuts off is a hacker's dream. Why? Think of it like this. Would you leave your new sports car unlocked, with the keys in the ignition and the engine running all day long? Not if you don't want it stolen. Hackers like "always-on" connections like DSL, cable modems and T1 lines because they're always there and they're predictable. This isn't to say that broadband connections are bad. Quite the contrary. Broadband is a great technology. Users just need to make sure they're using the appropriate level of protection that a firewall solution can offer.

Hacking, whether it's into your company's network or your personal computer at home, can have serious consequences. For example:

• Lost Data - What if someone deleted data on your company's network? What if you didn't have that data backed up? How much would that cost you?
• Down Time - Don't you hate it when a customer calls and you have to tell them your server is down? Do you think that customer is going to buy from one of your competitors? Probably.
• Computer Jacking - Do you like impersonators? Well, hackers who get control of your computer can launch attacks against other networks using your computer. When the cyber police find out, guess who they're going to be looking for?

• Denial of Service (DoS) - Denial of Service attacks are designed to prevent users from accessing a service or resource like a company's public Web site on the Internet.
• Viruses - A virus is a computer program that attaches itself to another program and spreads from file to file when that program is run.
• Worms - Worms are similar to viruses, except that instead of spreading from file to file, they spread from computer to computer.
• Trojan Horses - Like the ancient Greek saga, a Trojan horse is a gift with a little something extra inside. Unfortunately this "gift" usually causes serious problems for your computer.

Firewalls are a great way to protect your business or home network against attacks from intruders. They're designed to defend against attack by implementing a series of rules that permit, or deny, traffic to pass between your network and the Internet. Based on the way these rules are set, the inbound and outbound flow of information maybe extremely tight or very relaxed. The trick is to maintain a balance between your company's need for security and your employees' need to get their work done without interference.

So what else do firewalls do besides screening email and Web requests? In general, firewalls should have the following functions at a minimum:

• Stateful Packet Inspection - Stateful Packet Inspection is a smarter form of packet filtering, which inspects headers of network "packets." It blocks any packet arriving at the firewall claiming to be a solicited response.
• Network Address Translation (NAT) - NAT is a technique that hides the IP addresses of your internal computers from prying eyes by replacing them with a single public IP address.
• Application Proxy - This service allows firewalls to inspect more than just packet headers before deciding whether or not to allow a packet to pass through.
• Monitoring and Logging - Keeping records of attacks is important. It will help you analyze your security needs and provide you with feedback on the performance of your firewall.

• Malicious Authorized Users - These are people on the internal network who are already behind the firewall, which makes this threat difficult to defend against.
• Social Engineering - Sometimes hackers obtain information by calling employees and posing as a co-worker or someone else in the company doing a routine check.
• Viruses, Worms and Trojan Horse Programs - Firewalls scan network traffic for these threats, however the programs are changing constantly, making them hard to detect.
• Poor Network Administration - A firewall is only as effective as its programming. It's up to the network administrator to determine which network traffic should be allowed to pass and which shouldn't.