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Firewall software and Internet security

What are the threats?

There are over a billion people using Internet on daily basis. We are doing this from home and from our workplace; from our personal computers, laptops, mobile phones and TV sets; to search for information, to communicate with other people and to buy and sell goods and products. There is more - just think about the personal information that is stored on your computer - your e-mail messages, your personal photos and videos, chat logs, browser history, history of the all recent documents that you have read or created.

What happens if all this information falls in the wrong hands? Disaster. But how this could happen? The information is on your computer and you never send your personal information over the Internet. The dark truth is that there are countless ways for people with malicious intentions to invade your privacy. All they have to do is to place a small program (malware, trojan or virus) on your computer. The malware than will search for valuable information and will send it to its creators. After that they will most probably use your computer as a tool to infect other computers, to attack Internet sites for profit and to send spam messages.

How to protect your information? The best strategy is to create a multi-layer defense around your computer. The first important step is to remove and shred all private information that is not useful anymore but still can be dangerous if stolen. You can do this with the powerful privacy protection tool Mil Shield that will automatically clean all online and offline traces from your computer.

Click here to download the free trial version of Mil Shield 7.2
3.65 MB - 25 sec with broadband or 10 minutes with dial-up link

In order to understand the other precautions you can take, lets see which are the most common ways to steal information and get control over your computer:

  • Infecting of the computer through download of malicious program. One of the great advantages of the computers is the vast variety of programs that can be downloaded and installed. Most of these programs are genuine and can be trusted but more and more viruses, trojans and rootkits disguise themselves as useful programs. One special case are the modified versions of respected programs that are infected with malware and adware or the so called cracks for popular programs.
  • Infecting through files that are not looking like programs at first glance. For example you may download a song or a video file from the Internet and it may contain an executable file. Another common example are the screensavers, which are programs and are just as dangerous as any other program.
  • Using security "holes" in the operating system or popular applications. The so called exploits use the security problems or "holes" that are unintentionally left open in every major operating system and many popular applications. While most software companies are releasing security updates relatively quickly, most users never upgrade their software or it is too late - they are already infected and closing of the security "hole" does not remove the malware that is already on your computer.

In the first two cases above, you can prevent the infection if you are careful not to download programs from suspicious sources (always prefer downloading from the site of the author of the software or at least make sure that the download link points to its site). However, it the third case, you can not do anything to stop infection because there is no need to download and install anything - sometimes just a browsing of an infected Web page is enough to get you infected with malware.

The dedicated antivirus and anti-spyware programs help but they suffer from the same problem as the security updates - when the malware is included in their virus definition updates, it is already too late for the vast majority of infected PCs. Furthermore, they degrade the speed and usability of your computer (sometimes to a crawl) because the constant scanning of all files and processes is very demanding task.

Here comes the essential role of the firewall in the multi-layer defense of your computer. The firewall serves as a guardian, who monitors everything that your computer sends to or receives from the Internet (or the local network, if your computer is connected with other PCs from your house or your company). Mil Firewall is an easy-to-use personal firewall program, which makes sure that you are in full control of what goes in or goes out of your computer.

Click here to download the free trial version of Mil Firewall 2.2
2.8 MB - 20 sec with broadband or 6 minutes with dial-up link

In the next part of this article you will see exactly how the firewall protects your computer.

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How the firewall protects you?

So, how exactly the firewall protects your computer and the important private information on it? To answer this question, we will need some background information about how the Internet works. Although this is very big topic, we only need a simplified explanation. If you want a better understanding of all the inner workings, you can refer to Wikipedia or other online in-depth publications.

In general, the Internet is a global net of all connected computers. The structure of the Internet is not essential for our discussion. It is sufficient to say that the information between all connected computers is exchanged in small data units, called packets. Each packet can travel along a long and twisted route, passing though dozens or even hundreds of other computers, before reaching its destination. In order to understand each other, all computers use a common set of rules, called Internet Protocol (IP). Each computer on the Internet has its unique address, called IP address. For example the computer that contains (hosts) the Web site of CNN has IP address 157.166.226.26.

Lets see what happens when you go to the web site of CNN (www.cnn.com). Because it is not very convenient to remember such numerical addresses, there is another protocol - DNS, which is used to convert the name www.cnn.com to the IP address of the same computer. To do so, your computer sends a DNS request packet to another computer (called DNS server) and asks it for the IP address of www.cnn.com. The DNS server sends a DNS response packet with the requested information and our computer is ready to send another request packet to the computer of CNN and then waits for its response, which will contain the requested web page.

As you can see, in vast majority of cases, your computer acts like a client - it sends request packets to other computers (called servers) and waits for their response. Please note that in this case your computer initiates the connection and the connection is outgoing. This leads us to the simplest type of firewall - one that blocks incoming connections and allows all outgoing connections from your PC. Examples of such firewalls are the built-in firewalls in Windows XP and Vista. While this type of firewall provides some protection, it leaves a lot to be desired because it makes one dangerous assumption - that all programs or your computer are not malicious and can be trusted to create outgoing network connections as they want.

More advanced firewalls, like Mil Firewall, are inspecting both incoming and outgoing connections. Furthermore, they remember which program is initiating each connection and then use this information to do better job without getting in the way (also called stateful inspection). However, there is another drawback - the more advanced firewalls tend to use a lot of CPU and network resources and slow down your computer.

With the special firewall protection scheme, used in Mil Firewall, you do not have to sacrifice the speed of your computer in order to block hacker attacks and malware. Mil Firewall is the fastest firewall software and it is very flexible and powerful.

Click here to download the free trial version of Mil Firewall 2.2
2.8 MB - 20 sec with broadband or 6 minutes with dial-up link
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Conclusion

As we saw the firewall software is essential part of the computer defense against malware (viruses, trojans, rootkits, spyware, adware) and direct malicious attacks both from outside and inside of your computer. The good firewall software must be able to provide full network protection without sacrificing the speed of your computer and your network access. In order to be safe, keep in mind the following things:

  • Never install software from shady or suspicious sources. Always download the programs from the websites of their authors or from other respected sites on the Internet.
  • Use a firewall to monitor and block all attempts from programs on your computer to send information over the Internet if you have doubts about the need of network connection for the specific program purpose. For example, if a program that claims to be from Microsoft, tries to connect to website www.blackhat.co.tw, you should not allow it to happen. Mil Firewall will warn you about any such attempt and you will be able to choose what action to be taken.
  • Do not assume that you are protected because your computer is behind a corporate or hardware firewall. The firewall software must be installed on every computer because otherwise it only takes one PC to become infected and very fast all computers in the local network will be compromised.

If you follow the above simple rules, your online and offline computer experience will be much safer.

Click here to download the free trial version of Mil Firewall 2.2
2.8 MB - 20 sec with broadband or 6 minutes with dial-up link
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