Viruses, computer diseases

2002/11/15 Mendiburu, Joana - Elhuyar Zientziaren Komunikazioa | Waliño, Josu - Elhuyar Fundazioa

• Hardwarea

Viruses are not a mystery. Viruses are computer programs whose main objective is reproduction. When played, they hide within other programs and when this program is opened, the virus is also activated. Therefore, it is said that the file is "infected" because it carries a virus inside. Viruses reproduce in a hidden way and, as far as possible, without the user realizing them, extending them from one machine to another. However, because they are programs, they can aspire not only to proliferate but also to generate other problems.

Until network deployment, viruses spread through them.

Among other things, viruses can cause loss of information. Most of the time they just show special characters on the screen, but in many cases they can get to delete files, mix information from the hard drive or jam the computer.

Three types of viruses

There are as many types of infection as type of virus, but depending on the part that pollutes, three main types of viruses are distinguished: those that damage the file, those that alter the functioning of the macros and those that target the system.

Until recently, viruses that infect files were only located in files of programs with .COM or .EXE extension, as well as in .SYS, .OVL, .PRG and .MNU files. In this way, every time the program was started, the virus started. However, the improvement of common programs has generated another type of virus:

Macrobirus

Macro-viruses destroy small sections or program programs like Excel and Word, macros. For example, the Word spell checker depends on a macro. And, as already indicated, some viruses alter the role of these macros and can even alter or even delete the information contained in the document.

These systems have allowed to create cross-platform viruses that attack both PC and Mac platforms. So far most viruses attacked PCs, but as the infected Word document can be used as in the Word of Mac PC, the macrobirus is activated on one or another computer.

Since computers are connected viruses have spread a lot through email.

Finally, there are viruses that attack the system. Your goal is to control the essential information stored on the hard drive. That is, basic information for the correct ignition and use of the computer. These viruses infect some areas of the system found on the boot disk. Every time the computer is turned on, the virus is activated in memory, which is why they are especially dangerous. If they are located in the boot sector of the floppy disk, the playback system to another computer is simple.

However, do not think that a virus will begin to deteriorate after entering your system. Viruses are not activated as they are copied. Some are usually activated on a certain date (in the case of the well-known Friday 13th or Jerusalem viruses) and others are waiting for the user to take a specific action or to perform a number of actions (for example, those that are activated when opened in word 43 times).

There are also random activations. Many times, in addition, the damage caused by viruses is not a loss of information, but a waste of resources of our system, since they occupy a lot of space in the hard disk or in memory.

Antivirus...

The byte maps of virus infected files are usually modified and their detection is enough to know that the virus is there. However, this is not easy and, in addition, the change produced by some viruses is usually quite normal, but that of others does not, so there may be problems when detecting them.

It is recommended to use antivirus programs to minimize problems and damage. Antivirus detect the presence of viruses and remove or disinfect them from the system. They have a virus database that they know and compare their data with the byte map of the files. This system also allows to detect the presence of new viruses that do not appear in their databases.

Prevention is the best way of treatment, so most anti-virus programs apply permanent vaccine protection to our system. Thus, when entering a floppy disk, or when running any application, the antivirus performs a check to make sure that there is no virus and if found, displays a message to the user and blocks the computer.

In any case, viruses always find a slot to access the computer system and therefore watch for viruses all year round!

Basque antivirus?

Although viruses are extended to most systems, the world of PCs has been the most affected by virus aggression. There are more than 15,000 viruses and 5 new viruses are created every day. Mac has not suffered so much virus attack, as on this platform there are only 40 known viruses. However, special care should be taken with them. The most widespread antivirus on the PC market is the one developed by a Bilbao company, but without version in Basque. However, on each platform there are many anti-virus programs. Here we recommend some:

Antivirus for PC:

• Panda Antivirus . This antivirus also controls viruses that can reach you by email. It also works with Windows 98. ( www.pandasoftware.es). Fortunately it also has a version in Basque.
• Norton Anti-Virus . The known Norton antivirus does not need presentation either. ( www.symantec.com/avcenter/index.html).
• MacAfee Virus Scan. It is also a very popular antivirus. ( www.nai.com/default_mcafageasp).
• Dr. Solomon’s Software . This is the most widely used antivirus in the UK. ( www.drsolomon.com).
• IBM Anti Virus . The antivirus of the well-known IBM house also has its place in the market. ( www.av.ibm.com).

Antivirus for Macintosh:

• Although here there are also several antivirus, Disinfectant is the most used. Free pickup anywhere on the Internet.

A new self-executable e-mail virus appears: ‘Appix.B’

Computer security companies announce the emergence of a new email virus: PPP. The feature of this virus is that it is activated by just viewing the message.

The name of the attachment sent in the e-mail may be PamAnderson.scr, Jolie.scr, AnnaKournikova.scr, xxx.scr, FreeSex.exe, TvTool.exe, Flash Get.exe, WarezBoardAccess.exe or Undelivaremail.exe.

By activating this file, the virus reaches all addresses of your Outlook Express agenda. In addition, it creates in the Windows directory a copy of the virus, the APPBOOST.EXE file.

Panda Software has not yet reported the impact of this virus, but it seems that Appix.B spoils some of the applications in memory.

Buy new computer (I)

Starting the new course, many will need a computer at the request of your children or for your work. I will try to give some tips to help with the purchase.

Knowing for sure that you need a computer, the first question is always: what computer will I buy? Another question is answered to this question: Why do I need the computer?

95% of home computers are used to write texts, surf the internet and play. For the first two jobs it is enough with any computer, not of last generation, but an old one. The last generation computer will ask for it games. I write this text and will send it online with an old Pentium 133. With this I do not mean that you buy the old computer, but that to buy the pointer is useless. If your goal is to play, then yes, the games require a computer with the latest advances.

Many believe that buying a state-of-the-art computer will age later: Lie! The computer will be given to you whether it is 1500 Mhz or 800. For example, about five years ago, the store had to choose between Pentium 66 or Pentium 75. At that time it was normal to think that 75 would last longer, but it is ridiculous compared to current speeds.

Therefore, never go to the last generation computer, unless you are very clear. You buy the computer you buy, within three years will be an old junk. More in the next.

Posted in Zabalik.