Do you have any information in your computer that you would not want highlighted on the front page of a major newspaper? If you answered yes, you need a firewall. Without a firewall, anyone can access all the information in your computer.

A firewall is a software program or hardware that constructs an invisible barrier between your computer and the internet. It prevents unauthorized users from gaining access.

PING (Packet Internet Groper) is a  program that sends an ICMP (Internet Control Message Protocol) to test if a destination (your computer) is online. It sends out a packet that generates an echo
and waits for a response. This is how someone can see if you are online at any given time and is the basic idea behind “chat” and “messenger” services.

Zone Alarm is suitable for the personal computer. This type of firewall is called a Dual Host Gateway. It filters all communications, is user friendly, and lets you know when someone is trying to gain unauthorized access to your computer.

For network systems, there are two basic types of firewalls. The first is a  Demilitarized Zone Firewall that puts a buffer zone between the internet and a computer. All information passes through the buffer zone. This usually has a computer between the protected computer and the internet and is most suited for the small business. The second kind is a Screened Host Firewall System which is software that organizes a router (which is a way-station that collects and selects the best route to forward data packets). This filters every communication.
A Linux box (hardware) can be used as a firewall. For a comparative listing of intrusion detection software, see the June 2000 issue of SC Magazine.

So, you think your computer is safe from intrusion?
Take the Hacker Whacker test and see if your computer has an open back door.  If it does, you may want to check out Shields UP!.

Remember to maintain the most current version of your anti-virus program and the latest security patches for your browser.

If your intrusion detection software reports someone trying to get into your personal computer or your major computer network, you can report this to the United States Secret Service at 202-406-5850.

Firewall Articles

The Beginning of the End for Firewalls?

Rethinking the Firewall as a One-Way Mirror

Rising SSL Traffic to Degrade Firewall Performance

US Cracks China’s Firewall

Non-Congress States’ Firewall Send NCTC in Freezer

China’s ‘Great Firewall’ May Not Actually Isolate Internet Users

Disabled firewall leads to $400,000 HIPAA fine

Identity theft: What you need to know

Embedded firewall software protects against attacks

Free firewall configuration search tool

The Great Firewall of China

Check Point bakes anti-malware tech into firewall bricks

At last, a firewall for your car’s black box

Shutting down the internet: Thou shall not kill

The internet of things need firewalls too

Scaling the great firewall

What are the benefits of firewall security?

How does unauthorized data leave your agency?


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