Virus Control
On the Internet the term Virus is used as a generic term to cover a number of different malicious programs or pieces of code that replicate themselves by attaching to shared programs. Some Viruses can be annoying yet harmless while others can delete files or seriously disable your computer.
Currently e-mail seems the most popular way Viruses are transmitted. Some Viruses can access an infected computers personal e-mail address book to transmit themselves from one machine to another. When accessing the Internet or any other network it is important to always use an AntiVirus Security Solution.
Brief History of Viruses
The first virus in the wild actually predated the experimental work that defined current-day viruses. It was spread on Apple II floppy disks (which contained the operating system) and reputed to have spread from Texas A&M. It was apparently named Elk Cloner and displayed a little rhyme on the screen.
The First Documented Experimental Virus was created in 1983 -
In Fred Cohen's paper Computer Viruses - Theory and Experiments from 1984, he defines a computer virus and describes the experiments he and others performed to prove that the concept of a computer virus was viable.
In the paper he states that on November 3, 1983, the first virus was conceived of as an experiment to be presented at a weekly seminar on computer security. The concept was first introduced in this seminar by the author, and the name 'virus' was thought of by Mr. Len Adleman. After 8 hours work, on a VAX 11/750 system running Unix, the first virus was completed. Within a week, permission was obtained to perform experiments, and 5 experiments were performed. On November 10, the virus was demonstrated to the security seminar.
The first MS-DOS PC virus was released in 1986, when two brothers from Pakistan analysed the boot sector of a floppy disk and developed a method of infecting it with a virus dubbed "Brain". That same year the first PC-based Trojan was released in the form of the popular shareware program PC-Write . Virdem was also found this year; and is often called the first file virus.
From relatively humble beginnings, Viruses have become a huge global threat. It's essential to remain on guard against these dangerous predators at all times.
Types of Viruses
Trojans and Worms are probably the most common Virus types. Below is a summary of each Virus type.
Trojan horse program
A Trojan horse program is a malicious program that pretends to be a benign application; a Trojan horse program purposefully does something the user does not expect. Trojans are not viruses since they do not replicate, but Trojan horse programs can be just as destructive. Many people use the term Trojan to refer only to non-replicating malicious programs, thus making a clear distinction between Trojans and viruses. The name "Trojan" is used for this type of program because the program appears benevolent at first, however it actually is dangerous.
Worms
The Worm type viruses are computer programs that replicate themselves. The name Worm is an abbreviation of Write Once, Read Many. Worm Viruses access an infected computers personal e-mail address book to transmit themselves from one machine to another.
Keeping your computer Virus Free
Here's some tips on how to keep your computer virus-free.
- Do not open any files attached to an email from an unknown, suspicious or untrustworthy source.
- Do not open any files attached to an email unless you know what it is, even if it appears to come from a dear friend or someone you know. Some viruses can replicate themselves and spread through email. Better be safe than sorry and confirm that they really sent it.
- Do not open any files attached to an email if the subject line is questionable or unexpected. If the need to do so is there always save the file to your hard drive before doing so.
- Delete chain emails and junk email. Do not forward or reply to any to them. These types of email are considered spam, which is unsolicited, intrusive mail that clogs up the network.
- Do not download any files from strangers.
- Exercise caution when downloading files from the Internet. Ensure that the source is a legitimate and reputable one. Verify that an anti-virus program checks the files on the download site. If you're uncertain, don't download the file at all or download the file to a floppy and test it with your own anti-virus software.
- Update your anti-virus software regularly. Over 500 viruses are discovered each month, so you'll want to be protected. These updates should be at the least the products virus signature files. You may also need to update the product's scanning engine as well.
- Back up your files on a regular basis. If a virus destroys your files, at least you can replace them with your back-up copy. You should store your backup copy in a separate location from your work files, one that is preferably not on your computer.
- When in doubt, always err on the side of caution and do not open, download, or execute any files or email attachments. Not executing is the more important of these caveats. Check with your product vendors for updates, which include those for your operating system web browser, and email. One example is the security site section of Microsoft located at http://www.microsoft.com/security
To help you keep your computer safe, Optus has made it possible for you to download anti-virus software at Security: Spam & Viruses.