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A Guardian Angel for Your Computer

Although antivirus software is necessary, it's not the answer to everything. You need a guardian angel in the form of a firewall to protect your computer from hackers.

We are all well aware of the risks that accompany Internet use. We know not to automatically open e-mail attachments and have installed antivirus software and update it regularly. But is that enough to prevent hackers from accessing your computer and stealing your passwords? It may not be. Although antivirus software is essential, it's not the answer to everything. Antivirus software only protects your computer from virus attacks but not from intrusion attempts, remote control or attacks attempting to block your computer. Using a firewall can eliminate these threats.
Firewalls are often considered necessary only for companies, and the general public is not particularly aware of their functions. According to the most recent studies, hackers are increasingly targeting home Internet users. Here are a few facts about firewalls.

What is a firewall?
The main role of a firewall is to act as a filter between your computer and the Internet. It is software that monitors all incoming and outgoing data. When it detects an unusual connection such as a hacker intrusion, it blocks it immediately.

Firewalls do more than just stop attacks from the exterior. They also prevent sensitive data from leaving your computer. You can decide to authorize or prevent access to certain sites or Web services. To do so, firewalls use a multi-level filtering system, which can filter by application, address or package. Certain applications like chat programs, instant message programs, and downloading and FTP exchanges pose a great security risk because they encourage virus propagation and hacker intrusions. You can configure your firewall to block access to these services if you do not want to take these risks or if you do not want members of your family to use these applications. Your firewall will then close ports these applications use to connect to the Web. Filtering by address allows you to monitor Internet use.

Filtering by package checks the "health" of data transmitted via TCP/IP ports (channels used for receiving and sending data on the web). Firewalls make sure data conforms with normal connections and block transfers of mass data to avoid saturating your computer and to prevent any intrusion attempts. Firewalls can also make your computer "invisible" on the Web. Your computer will not respond when hackers send data during a port scan or vulnerability check.

I have a modem connection. Do I need a firewall?
Risk is determined by the duration of the Internet connection, not the type. According to Symantec studies, Internet users with a modem connection who spend a lot of time on the Web are just as susceptible to risks as those who are connected all the time. Hackers can determine their IP addresses on forums or chats. If you are a "Web junkie," you need a firewall for protection.

The risk is even greater for broadband users, who are connected constantly. Their IP addresses hardly change or do not change at all, and the amount of bandwidth they use is more attractive to hackers. Firewalls are therefore essential.

Are firewalls difficult to use?
Most users are hesitant about installing a firewall because they do not want to slow down their computer or because they are afraid of the complexity of configuring the equipment. But these days, there are firewalls that are intended specifically for the general public and do not require any specialized technical knowledge. Intuitive interfaces often facilitate use. A smart configuration that only restricts those Web applications that actually pose a risk will not slow down your computer.