COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School COMPUTER AND INTERNET SECURITY LESSON 9

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School LESSON OVERVIEW  COMPUTERS & SECURITY  WHAT IS A VIRUS?  SECURITY TYPES AND WEBSITES  DEVELOPING AN EFFECTIVE ANTIVIRUS STRATEGY  SECURITY TERMS

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School COMPUTERS & SECURITY Need to protect  Data  Ability To Use Our Computers 1 of 3

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School COMPUTERS & SECURITY Major Sources Of Danger  Running malicious code on your machine due to system or application vulnerabilities or improper user actions  Carrying infected machines (laptops) in from off site Internet Is A Dangerous Place  We are constantly being scanned for weak or vulnerable systems; new unpatched systems will be exploited within minutes. 2 of 3

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School COMPUTERS & SECURITY  Computer Security is not an add-on or something external, it is part and parcel of everything you do with computers (analogy with ES&H)  Not “one-size-fits-all”, but appropriate for the needs and vulnerabilities of each system  In most cases, it is simply common sense plus a little information and care 3 of 3

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School WHAT IS A VIRUS? A virus is simply a computer program that is intentionally written to attach itself to other programs or disk boot sectors and replicate whenever those programs are executed or those infected disks are accessed. 1 of 3

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School WHAT IS A VIRUS? Viruses, as purely replicating entities, will not harm the system as long as they are coded properly. Any system damage resulting from a purely replicating virus happens because of bugs in the code that conflict with the system's configuration. In other words, a well-written virus that only contains code to infect programs will not damage the system. The programs will contain the virus, but no other harm is done. 2 of 3

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School WHAT IS A VIRUS? The real damage _ the erasing of files, the formatting of hard drives, the scrambling of partition tables, etc.--is caused by intentional destructive code contained within the virus. The destructive part of a virus is programmed to execute when certain conditions are met, usually a certain date, day, time, or number of infections. 3 of 3

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School SOME TYPES OF VIRUS  Boot Viruses  Program Viruses  Multipartite Viruses  Stealth Viruses  Polymorphic Viruses  Macro Viruses

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School SECURITY TYPES  Account Security  Server Security  Third Party Security  Software Security  Copyright

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School DEVELOPING AN EFFECTIVE ANTIVIRUS STRATEGY Who needs this? Anyone who does a lot of downloading, or accesses diskettes from the outside world on a regular basis should develop an antivirus strategy.

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School DEVELOPING AN EFFECTIVE ANTIVIRUS STRATEGY (1) The most important weapon in an antivirus arsenal is a clean, write- protected bootable system diskette.

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School DEVELOPING AN EFFECTIVE ANTIVIRUS STRATEGY (2) A second effective defence against viruses is a clean backup of the hard drive.

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School DEVELOPING AN EFFECTIVE ANTIVIRUS STRATEGY (3) The third part of an antivirus strategy should be antivirus software, preferably more than one package since no one product can do everything. There are many products out there to help guard against viruses.

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School SECURITY TERMS  Encryption  Digital Signature  Firewall  Hacker  Spam

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School ENCRYPTION  Symmetric Encryption  Asymmetric Encryption  Combination Symmetric And Asymmetric Encryption

COMPUTER SYSTEM FUNDAMENTAL Genetic Computer School FIREWALL TECHNIQUES  Packet Filter  Application gateway  Circuit-level gateway  Proxy Server