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The following is an essay that is aimed at helping you better protect your computer against the various threats that exist in the internet.

How can I be protected ?

As great as a tool, the internet is, it is also full of potential threats to your security and the data you store in your computer. There are many types of threats that exist and in many different forms.

As a first step we will try to explain (albeit very briefly) what each type of threat is.

  • Viruses : Viruses include a wide variety of threats but as a general rule a computer virus is considered as a program that can replicate itself to different machines and has the ability to cause harm on the computer that it is installed on. Viruses can infect computers wither via the execution of a file containing the virus code or via some vulnerability (exploit) in the operating system of target computer.
  • Trojans : These programs, known as Trojan Horses, usually come inside another application that many times is not even related to the Trojan itself. A trojan is a program that primarily grants some type of remote access to a computer to an outside party. Trojans are also known as backdoor programs because in effect they open up a door to a system allowing a malicious hacker to take either complete control of the machine or use it covertly without the knowledge of the person whose machine has been compromised.
  • Keyloggers : Programs that like trojans usually come bundled inside a different application and almost always run covertly on the infected machine. Keyloggers record all keyboard keystrokes and the information associated with the application or webpage that those keystrokes were made for. For instance if your computer is infected with a keylogger and you visit your favorite webmail website, the keylogger, will record your username and password as you enter them into the fields provided by the website to log in. After collection of the information, the keylogger will send this information over the internet to some pre-specified address.
  • Spyware/Adware : These are programs that can be installed in a system much the same way as any virus, but also come bundled in an ever increasing number of shareware/free applications. The main purpose of these programs is to record user activity on the internet (and subsequently mail this information to some collection agency) or to force the display of advertisements on the infected computer. Many of these programs do not carry any immediate harmful payload, but even those can easily destabilize the performance of any computer. Other spyware programs contain additional trojan/backdoor programs, making them an even greater threat.
  • Diallers : Nasty little programs that can take over your modem and initiate calls to dubious calling services that charge you by the minute or second for the time you are connected. If you are using a dial up connection (PSTN/ISDN) to connect to the internet you should ask your telephony provider to provide you with an itemized report of all your calling charges and then make sure to examine this report to determine if any unwanted calls have been made from your number. Diallers are treated mostly as viruses in terms or fixing them.
  • RootKits : Rootkits are similar to trojans. They difer from most viruses in the respect that they do not try to spread to other computers. Their foremost function is to grant unrestricted access to a compromised machine and hide their presense from any detection tool. Most rootkits are created in such a way as to hide within the operating systems core, and even make sure to shut themselves down in order to avoid detection during scans. Unfortunately there are very few tools that provide adequate detection of such programs and since many Kernel-mode rootkits can even hide the processes from the machines active process list, their detection is even more dificult.
    F-Secure has a comercial product (currently in Beta - and available to download) : F-Secure BackLight
    Also there exists an excellent freeware tool by SysInternals called RootKitRevealer. This programs results can be a bit complicated to understand for the non technical user.
    Both these programs are meant for Windows NT - 2000 - or XP (win98 is not supported).


The first step in securing your PC is and always should be to keep your operating system uptodate. Microsoft's various windows operating systems offer an online updating service, which should either be set to automatically check for newer versions or the user should manually make it a habbit to check for newer version on a very regular basis. There are security holes that no measure of protection will patch unless the operating system is updated.
Related Links : http://windowsupadte.microsoft.com

As a second step it is imperative to have a firewall installed in your computer. A firewall is a shield between your system and the outside world (i.e the internet), which can filter what data can move in or out of your system. The best solution is to have a hardware firewall. A hardware firewall is much more dificult to fall victim to an exploit or virus that manages to infect your system, but hardware firewalls are more complicated to configure and may not be best suited for users without extensive knowledge in computers. Today, many modems come with a built in firewall which helps protect the computer connected. Alternatively you can install a software firewall which is a program that can do the same job, software firewalls however are vulnerable to a malicious program that manages to get itself installed in a computer.
Related Links : http://www.zonelabs.com/

Thirdly you should have an antivirus running on your system. The antivirus installed should have realtime scanning capabilities, which essentially means that it scans memory, processes, programs and mails while the computer in operating and not just when you manually initiate a virus scan of the computer. Also the antivirus program needs to be updated on a very regular basis, an antivirus tool that is not getting updated is almost as bad as not having one. The best antivirus tools have automatic updating tools that scan on regular intervals or even every time you connect to the internet for updates from their respective vendor's websites. Keep in mind that different antivirus tools have different capabilities and sometimes it may be good practice to have more than one available. However please note that it is not advisable to have two antivirus tools protecting your system in real-time, rather have one as your primary antivirus tool and real-time protection, and also keep (an updated) second antivirus tool available with which you can run manual scans on a regular interval (like once a week).
Trojans are not always detected by antivirus tools and it may be necessary to have an additional anti-Trojan tool.
As antivirus tools (even the best of them) can only scan for viruses they know about, and in some cases use heuristic analysis to determine if an unknown file is a virus, they tend to miss on some new viruses which can make their way to your computer. It is imperative to never open an attachment even if it comes from someone you know well, unless you know what it is that you are receiving. Here is a list of very dangerous file extensions which you should shy away from almost always. Remember that its not worth risking a virus infection just to simply see what the attachment is.
If your Operating system and software is up to date the risk of getting a virus due to an exploit in the browser or mail client is rather minimal.

Related Links : http://www.grisoft.com/

Another Very important step in protecting your surfing experience is to protect your browser from the multitude of exploits that exist in various (albeit mostly dubious websites) that have been known to install malicious programs or highjack your homepage location. There are several tools that can help you protect your browser from such threats, but you will need also to manually adjust your settings to implement better security measures by going into your browsers internet options and under security sellect the highest level of security.
Related Links : http://www.javacoolsoftware.com/

Avoid using pirated copies of software as many virus and trojans come bundled inside pirated copies of software, where hackers have reverse engineered their own software inside the pirated copy.

Another source of danger is file-sharing networks, if you choose to use such networks it is highly advised to take the time and familiarize yourself with each of these networks that you will be using and basically educate yourself to the point where you are able to tell which files may be dangerous, before downloading them. Diving into using any filesharing network without the necessary knowledge almost guarantees that you will run into probelms with viruses.

As a lst tip always remember to update.... update everything, your operating system, software you use, antivirus or other protection measures. Keep your programs up to date is the most important part in preventing malicious programs from making your life dificult.