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

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