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Basic PC Security
Learn to protect your computer!
 Chapter 5 - Basic PC Security
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 As more and more people get online and as more get high speed internet connections, the need for a basic knowledge of PC (Personal Computer) security is great. Just as you learn to lock your door at night you need to learn to lock that computer also. Here are some statistics showing why you need good security practices. There is an estimated 53,000 different viruses floating around the net right now. Just one of those can infect millions of computers as the infamous "I Love You" virus did. 45 million users are estimated to have fallen victim to that particular code. The most disturbing statistic which I think is too low is that there is a 1 in 4 chance that you have some form of virus or worm on your system right now as you read this. Let's learn a little more about these nasty little programs.

  A virus is simply a program that can "infect or "contaminate" other programs by modifying them to include a copy of itself. Malicious viruses are typically detrimental to data or system integrity. A worm is different as it is an independent program that replicates itself crawling from machine to machine across network connections ( etc. the Internet ). It often clogs networks as it spreads and multiplies. A worm can me acquired e-mail or, as in the case of the "Code Red" worm, can be completely automated and propagate throughout the net without the user ever opening an attachment or knowing their PC was infected.

  OK now that we know what these things are, let us discuss how people get "infected". Probably the most widely known way is through e-mail attachments. DO NOT OPEN ATTACHMENTS!!! Don't even open ones from people you know. Many of these viruses look for the "contacts list" in the infected computers e-mail program and automatically sends itself to all those e-mail addresses listed. So if your friend Sue sends you e-mails often she probably has put you in her contacts list. If Sue gets infected her computer will send you the virus e-mail without her knowing anything is happening. The point is do not trust anyone. When you do receive an attachment e-mail the sender asking if they sent this to you. If this one act was followed most e-mail viruses would be stopped dead in their tracks.

 A close second in the ways to get infected is growing rapidly. If you use a napster-like filesharing service, whether it's Kazaa, Morpheus, or whatever, you can easily unintentionally download a virus. Here's one way it happens. Someone will write a virus and name it something people are likely to search for in a filesharing program. Let's say you are wanting that new song "so and so" sings. You go online log into Kazaa and search for the song. You select one, complete the download, and try to click on your new song to give it a listen. Nothing happens, no music plays. You just figure oh well, and then go download another version of the song. You are unaware but the file you downloaded first happened to be a trojan horse named whatever.mp3.exe. Many times Windows is set not to show file extensions so you wouldn't see that it is in fact a .exe (executable) file not a .mp3 (music) file. Once the Trojan is executed it installs a backdoor on your machine. This backdoor is like a hacker only entrance that you will not even know exists. Once they waltz into your computer they can either view, delete, add files, or add more viruses to infect others.

  This leads to the last way I'll talk about getting infecting, the worm. The worm is apply named as it is asexual and quickly crawls from machine to machine across a network. Worms usually take advantage of a program currently running on your system. In the case of the "Code Red" worm it exploited vulnerabilities in Microsoft's IIS server on Windows NT/2000 systems. The worm would install itself, copy itself, and then, from your computer, scan the Internet for more vulnerable machines to infect. It would then crawl to that machine over the Internet and start the process over again. The purpose of this worm was at a certain date and time it would stop spreading itself and turn it's focus on one particular website or IP address and then launch a denial of service attack. A denial of service attack is like getting thousands of people to circle the block of a business you have a grudge against. All the traffic would overwhelm the store and shut it down temporarily. Ready to learn how to protect yourself and/or keep yourself from being a participant in all this madness?

  The number one thing you should do is have an up to date antivirus program. I recommend Norton Anti-virus, but no matter which program yo use it needs to be updated at least weekly. One good thing about Norton's product is that it can automatically go online and download the last virus definitions. Next I would tell you to update your software often. As much as I dislike Microsoft they did do something right by make "Windows Update" available. These virus writers love to teach big companies like Microsoft a lesson by exploiting one or more of the many security holes Microsoft products have in them. When you update your software you are downloading patches among other things that close these holes to the viruses. Don't get this confused with upgrading software. Upgrading is installing a newer version of a piece of software. Updating is just usually fixing problems that have been found in your existing software. Updating is usually free. The Windows Update program is located in your Start Menu for those of you who have never used it. I would also recommend doing this weekly. Finally and especially for those of you on always on high speed connections, install a firewall! When you're on dail-up modems it's like living in the country you can leave your door unlocked and probably get away with it. However, when you get broadband it's like moving to the big city with your driveway leading directly to the freeway. You better lock your door! Hackers love unprotected cable or DSL users! I recommend Zone Alarm. It's free and about the best out there.

  In closing, hackers and people who write viruses and worms are not really interested in getting into your computer to look at your personal files. The only time they would have anything to gain from that is if you had top secret information or you your financial data on your home PC. These people normally just want to either prove to their buddies that they can write a virus and see how far it goes on the net, or they want to use your computer to help attack others. Just use your common sense online.

List to safe and secure computing:

  • Use and update your antivirus program.
  • Update all your programs especially Microsoft products. (i.e. Windows and Office)
  • Install a firewall. This is a MUST for DSL/cable users!
  • Do not open attachments without confirming with sender.
  • Do not download programs from questionable sites.
 end of Chapter 5
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chapter - 1, 2, 3, 4, 5

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