A virus is a program that may or may not attach itself to a file and replicated itself. It may or may not corrupt the data of the file it invades. It may or may not try to use all of the computer's processing resources in an attempt to crash the machine. If that seems vague , it's because viruses are tricky. They may be simple notes that say "hello" or they may attack and corrupt the files at the core of the system, causing it to crash. Viruses cann be divided into classes according to such characteristics as environment and destructive capabilities.
according to the environment, viruses can be divided into:
a. File
File viruses either infect executables files in various ways(parasitic - the most common type of viruses), or create file doubles(companion viruses), or use file system specific features(link viruses).
b. Boot
Boot viruses either save themselves in disk boot sector, or to the master boot record, or change the pointer to an active boot sector.
c. Macro
Macro viruses infect document files, electronic spreadsheets and databases of several populer software packages.
d. Network
Network viruses use protocols and computer network or email to sp[read themselves. There's is a large number of combinations - for example file boot viruses infecting both files and boot sectors on disk. As a rule these viruses have rather complicated algorithms of work, often use unusual methods of intrusion into the system, use stealth ang polymorphic tecnologies.
by : omz herue
0 comments:
Posting Komentar