Virus Ya Ntivirus

VIRUS AND VIRUS

CONTENT

• Concept virus

• Classification virus

• Viruses

• Antivirus Concept

• Protective measures

CONCEPT OF VIRUS

Speaking of virus in the network, there are many unanswered questions, among which are the following opinions:

• They are computer programs

• Its main feature is the ability to self-replicate.

• They try to hide their presence, until the explosion.

• Harmful effects on the host.

Talking more deeply about it, and one referring to the point, a computer virus is a computer program, as could be a word processor, a spreadsheet or a game. Obviously that's the end all closely resembling the typical programs that most people have installed on their computers. A computer virus occupies a minimal amount of disk space (the size is vital to go unnoticed), it runs without user's knowledge and is dedicated to self-replicate, ie, makes copies of itself and infects files, partition tables or boot sectors of hard disks and floppy disks to expand as quickly as possible. As said before computer viruses bear resemblance to the biological and the second is that the infected cells in order to replicate the first use files for the same function. In some ways it is a kind of "technological mockery" to nature. As the virus replicates tries to pass unnoticed as you can, try to avoid the "host" to realize his presence ... Until it comes to the "explosion". It is the height that marks the end of the infection and when it is usually accompanied by the hard disk formatting, deletion of files or messages of protest. But the damage has been practicing throughout the process of infection, because the virus has been dealing in the computer memory, has slowed the process and has "fed" the files it has infected.

The propagation through these machines, may be performed in various ways, by means of diskettes or through communication networks that connect a number of computers.

They perform regularly in assembly language (asm), but not all programs can be considered made in asm virus, because there are some operating system programs written in this language.

CLASSIFICATION OF VIRUS

Classification

Depending on where you are staying, the replication technique or the platform on which they work, can be classified into different types of viruses:

• Boot sector viruses (boot)

• File viruses

• Direct Action Virus

• Overwrite virus

• Virus Company

o Macro viruses

o Bat Virus

o Mirc virus

o Virus mutants

o Timebombs

o Infectors executable programs

Described in each consisting of these viruses.

Boot sector viruses (boot). They use the boot sector, which contains information on the disc type, ie, number of tracks, sectors, faces, size of the fat, start sector, etc. To all this we must add a small program that checks boot disk to boot the operating system.

Virus file. Traditionally infected files and executable types. Com and. Exe have been most affected.

• Direct action virus. Those who are not resident in memory and replicate when an infected file is executed.

• Overwriting virus. Corrupt file which houses the overwrite.

• Virus company. They take advantage of a feature of the two, by which if we call to execute a file without specifying the extension, the operating system will look first type com. This virus does not modify the original program, but when it encounters an exe file creates another type of the same name containing the virus with com extension. So when you type the name first execute the virus, and then it passes control to the original application.

Macro virus. A family of newly emerging viruses and expansion. These programs are using the WordBasic macro language, through which can infect and replicate through MS-Word files (doc).

Virus bat. Such orders virus uses two batch files, and manage to replicate and make harmful effects like any other virus.

Mirc virus. Come to be part of the next generation Internet and shows that the network opens new form of infection. It consists of a script for mirc irc client. When someone accesses an IRC channel where someone is infected, dcc receives a file called "script.ini", infecting the computer.

Virus mutants. Infect Are you make changes to your code, to avoid being detected or removed (Satan, Michelangelo, to name a few).

Time bombs. Programs are hidden in the system memory or on disks, files or typed executable programs. Com or. Exe. Pending a certain date or time to "explode".

Infectors executable programs. These are the most dangerous virus because it spread easily into any program (such as spreadsheets, games, word processors).

Viruses

The virus can be anywhere. In that floppy leaves a friend in the last file downloaded from the Internet. Depending on the type of virus infection process varies considerably.

The disc may have a virus infected file in the file fichero.exe for example. The user inserts the disc into the computer (of course not an antivirus scan or if it does it with an outdated antivirus) and look at the contents of the disc ... Some text files, a. Dll's,. Ini ... Ah, there it is, an executable. Let's see what you have. The user runs the program. Just then the program instructions are read and processed by the computer, but also processes other instructions that should not be there. The virus checks for already installed in the memory. If you see that is not yet contaminated passes this and you can to stay resident in it. From that moment everything running program will be contaminated. The virus will run all programs, but then copy itself and "stick" to the program executed "engordándolo" a few bytes. To prevent advanced users realize those hidden infection bytes more to look like they still have the same size. The virus quickly contaminate system files, those that are in use at the time and they are the first to run when booting. So, when the user restarts the computer the virus will be loaded into memory when running the system boot files contaminated and again take control of it, contaminating all the files that are in its path.

Maybe the virus is also "boot sector", ie when the computer act

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