DEFGEN2.CVP 910707 What and What Not Having established that viral programs copy themselves, and before going on to related types of programs, let me list a few things that viri are *not*. Let me first say that computer viral programs are not a "natural" occurence. These are programs which are written by programmers. They did not just appear through some kind of electronic evolution. Viral programs are written, deliberately, by people. (Having studied the beasts almost from their inception, I was rather startled when a young, intelligent, well educated executive proposed to me that viri had somehow "just grown" like their biological counterparts.) The popular press has recently started to publicize the term computer virus, but without giving any details other than the fact that viri are to be feared. (Often the reports talk about "main storage destroyed" and other such phrases which have very little meaning.) This has given most people the impression that anything that goes wrong with a computer is a virus. From hardware failures to errors in use, everything is blamed on a virus. *A VIRUS IS NOT JUST ANY DAMAGING CONDITION.* Likewise, it is now considered that any program that may do damage to your data or your access to computing resources is a virus. We will speak further about trojan horse programs, logic bombs and worms, but it is important to note that viral programs have common characteristics that other damaging or security breaking programs may lack. Viri are not just any damaging program. Indeed, viral programs are not always damaging, at least not in the sense of being deliberately designed to erase data or disrupt operations. Most viral programs seem to have designed to be a kind of electronic graffiti: intended to make the writer's mark in the world, if not his or her name. In some cases a name is displayed, on occasion an address, phone number, company name or political party (and in one case, a ham radio license number.) On the other hand, viral programs cannot be considered a joke. Often they may have been written as a prank, but even those which have been written so as not to do any damage have had bugs, in common with any poorly written program. The author of Stoned abviously knew nothing of high density floppies or RLL drive specifications. In fact, it appears that the trashing of data by the Ogre/Disk Killer virus, one of the most damaging, was originally intended to be reversible, were it not for an error on the part of the programmer. Any program which makes changes to the computer system that are unknown to the operator can cause trouble, the more so when they are designed to keep spreading those changes to more and more systems. However, it is going to far to say, as some have, that the very existence of viral programs, and the fact that both viral strains and numbers of individual infections are growing, means that computers are finished. At the present time, the general public is not well informed about the virus threat, and so more copies of viri are being produced than are being destroyed. As people become aware of the danger, this will change. copyright 1991, Robert M. Slade DEFGEN2.CVP 910707 ============== Vancouver ROBERTS@decus.ca | "A ship in a harbour Institute for Robert_Slade@sfu.ca | is safe, but that is Research into rslade@cue.bc.ca | not what ships are User p1@CyberStore.ca | built for." Security Canada V7K 2G6 | John Parks