Time and Logic Bombs

Logic and Time Bombs are designed to harm a computer at a specific time or day and only when a certain condition is met. Mail Bombs when triggered begin to mass mail a person’s email account causing it to overflow while either slowing the computer down or causing it to crash. Software that is inherently malicious, such as viruses and worms, often contain logic bombs that execute a certain payload at a pre-defined time or when some other condition is met. This technique can be used by a virus or worm to gain momentum and spread before being noticed. Many viruses attack their host systems on specific dates, such as Friday the 13th or April Fool’s Day. Trojans that activate on certain dates are often called “time bombs“. A couple of different packages to prevent these are AVG Anti-virus and Kapersky Anti-virus which i would highly recommend.

AVG Antivirus	Kaspersky Anti-virus
Size11.4MB	Size23.61MB
LicenseShareware30 day trial	LicenseShareware30 day trial
PlatformWindows 98, Windows NT, Windows 2000, Windows XP, Windows Vista	PlatformWindows 2000, Windows XP, Windows Vista
DeveloperAVG.co.uk	DeveloperKaspersky

Different kinds of Anti-Virus software

There are two kinds of anti-virus software, stand alone and memory resident. Stand alone has to be run and the user chooses a file, part of the pc to scan for threats. If a threat is found the user can then delete the problem file or quarantine the file and then try to repair it to return it to it’s original state. Memory resident software does the same as stand alone but is constantly running to protect the users pc, if a threat is found a screen will come up and prompt the user to take action. Most resident anti-virus packages will also scan email and webpages for threats. The anti-virus packages can be constantly updated to ensure that they are protecting against the newest and most recently discovered threats.