11-03-2011, 04:32 PM
Submitted by:
Sunil Sahu
presentation about viruses.pptx (Size: 515.85 KB / Downloads: 121)
Computer Viruses
What are computer viruses?
Computer programs which invade a computer and try to take over its functions, rather like biological viruses do with human cells.
Most of us must have dealt with computer viruses from time to time.
What is a virus?
A virus is a program that self-replicates
It is not data
You can only catch a virus by running a program
Your computer runs all kinds of programs
spread of Computer Viruses
Basic virus terminology
Virus
Self-replicating
Also called a worm
Trojan Horse
A program which appears to be valuable but has an unexpected consequence
Examples of risky file types
The following file types should never be opened:
.EXE
.BAT
.VBS
.COM
Worms
Worm - is a self-replicating program, similar to a computer virus. A virus attaches itself to, and becomes part of, another executable program; however, a worm is self-contained and does not need to be part of another program to propagate itself.
The TROJAN HORSE Virus
Boot Sector Viruses
Boot sector viruses reside in the part of the disk that is read into memory and is executed when your computer first boots up. Once loaded, the virus can then infect any other disk used by the computer
Typical things that some current Personal Computer (PC) viruses do
Erase files
Scramble data on a hard disk
Cause erratic screen behavior
Halt the PC
Many viruses do nothing obvious at all except spread!
Prevention
Anti-Viruses
Updates
More secure operating systems
e.g. UNIX
Anti-virus warnings
Notify the help desk when you receive a virus warning from Norton Antivirus, Mcafee Antivirus etc.
Most of the time, the virus software will detect and prevent the infection. However, the help desk can better tell you what to do.
Basic virus defense
Install antivirus software.
Make sure updates are current: No more than one week old.
Don’t open e-mail attachments.
Install a firewall on your workstation. (XP’s firewall blocks intruders but doesn’t block already installed viruses from going out. Good software firewall: Zone Alarm has a free version) Learn file extensions.
Scan your system regularly.
Don’t install new programs without first notifying IT.
Don’t visit unauthorized Web sites.
Sunil Sahu
presentation about viruses.pptx (Size: 515.85 KB / Downloads: 121)
Computer Viruses
What are computer viruses?
Computer programs which invade a computer and try to take over its functions, rather like biological viruses do with human cells.
Most of us must have dealt with computer viruses from time to time.
What is a virus?
A virus is a program that self-replicates
It is not data
You can only catch a virus by running a program
Your computer runs all kinds of programs
spread of Computer Viruses
Basic virus terminology
Virus
Self-replicating
Also called a worm
Trojan Horse
A program which appears to be valuable but has an unexpected consequence
Examples of risky file types
The following file types should never be opened:
.EXE
.BAT
.VBS
.COM
Worms
Worm - is a self-replicating program, similar to a computer virus. A virus attaches itself to, and becomes part of, another executable program; however, a worm is self-contained and does not need to be part of another program to propagate itself.
The TROJAN HORSE Virus
Boot Sector Viruses
Boot sector viruses reside in the part of the disk that is read into memory and is executed when your computer first boots up. Once loaded, the virus can then infect any other disk used by the computer
Typical things that some current Personal Computer (PC) viruses do
Erase files
Scramble data on a hard disk
Cause erratic screen behavior
Halt the PC
Many viruses do nothing obvious at all except spread!
Prevention
Anti-Viruses
Updates
More secure operating systems
e.g. UNIX
Anti-virus warnings
Notify the help desk when you receive a virus warning from Norton Antivirus, Mcafee Antivirus etc.
Most of the time, the virus software will detect and prevent the infection. However, the help desk can better tell you what to do.
Basic virus defense
Install antivirus software.
Make sure updates are current: No more than one week old.
Don’t open e-mail attachments.
Install a firewall on your workstation. (XP’s firewall blocks intruders but doesn’t block already installed viruses from going out. Good software firewall: Zone Alarm has a free version) Learn file extensions.
Scan your system regularly.
Don’t install new programs without first notifying IT.
Don’t visit unauthorized Web sites.