Firewall Basics

A personal firewall can be a valuable defense against these online threats, keeping your computer and your personal information safe.

What a Firewall Can Do For You
Firewalls function like their namesake by providing a line of defense between computers that share information. The purpose of a personal firewall is to control the flow of information back and forth between your computer and your Web server. A firewall examines all traffic routed between your computer and the Internet to see if it meets certain criteria. If it does, it is allowed in. If it doesn't, it is stopped. Protecting your computer from intrusion, the firewall keeps your machine from getting burned by destructive intrusions that could result in data loss or file corruption.

A firewall can give you the tools you need to protect your private information while connected to a public network:


• You may select which information you would like to protect, such as a credit card number or password. If you attempt to send that number to an insecure site - such as one that doesn't support sufficient encryption -- the firewall will alert you.


• Firewalls can also prevent Web servers from getting access to other sensitive data, like your address, while you're browsing.


• Cookies, small text files stored on your computer by a Web server, can be useful for surfing because they help other sites remember you when you revisit, eliminating the need to enter login information with each visit and keeping your shopping basket current. But they may also raise privacy concerns since they could be used to track your web surfing unknowingly;. With Norton Personal Firewall, you can block cookies on a site-by-site basis.


• You can also block Java applets and ActiveX controls, both of which may endanger personal information and computer security.


• In addition to controlling information, firewalls can let you know if anyone has tried to access that information using intrusion detection that notifies you and analyzes the data for patterns that may point to a weak spot in your security system.

Do You Need a Firewall?
A personal Internet security solution, featuring intrusion detection software, will not only protect data from viruses and hackers, but will also provide additional levels of privacy and anonymity. Symantec's Norton Internet Security 2003 includes features to prevent Web sites from tracking online activities, keep personal information private, and block unwanted banner ads and pop-up windows to create a secure, private, and efficient online experience for both local and remotely connected workers.

The key component to intrusion detection and data security solutions is a personal firewall. This component acts as the gateway for incoming and outgoing data on all Internet connections. Norton Internet Security includes Norton Personal Firewall 2003, and this software is also available as a stand-alone solution. Firewall software protects data from unauthorized access and alerts users to attempted intrusions. Other benefits include the ability to block unauthorized Java or ActiveX components and cookies from unfamiliar sites. A firewall is particularly important to consider if a small business uses an "always-on" Internet connection such as DSL or cable, and if remote access is common.