Newsgroups: comp.ai.alife
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From: trin0008@sable.ox.ac.uk (Rick Heylen)
Subject: Re: ALife Park
Message-ID: <1995May22.210042.20744@inca.comlab.ox.ac.uk>
Organization: Oxford University, England
References: <3o61j0$cbp@ns.cityscape.co.uk> <D8IyHB.4pA@runic.mind.org> <3p5kug$o1q@gap.cco.caltech.edu> <D8qMBK.LH@runic.mind.org>
Date: Mon, 22 May 95 21:00:42 BST
Lines: 56

There has been a spate of scaremongering posts declaring that a distributed
version of Tierra will evolve some sort of behaviour to disrupt computers
or overload the network. I would like to lay this misaprehension to rest.
There has also been some discussion about this topic being a fact free
science. I think that the problem is not so much that it's fact free as it's
thought free. Is there something mystical and profound about evolving 
programs (or creatures) in computer generated environments? No!
You would no more expect a computer-critter to infest your machine than you
would expect a computer simulation of a fire to melt the wires in your 
mainframe.
"Oh no!" I hear you say. 
"That's not the same at all! These computer creatures are fighting for 
their survival and will exploit any bug in the system to take total control
over your system and the network and probably the entire known world."
This is complete drivel.
The environment of tierra is simple enough to be provably secure. Not that
it needs anyone to bother to prove it. It's silly to think of an organism 
'escaping' the Tierran environment as the local 'laws of physics' 
prohibit it.
The 4*4*4 rubics cube has a large number of possible arrangements, 
probably several tens of orders of magnitude more arrangements than 
fundamental particles in the universe. Were I to suggest that there was 
some move which turned the entire cube to anti-matter and hence destroyed 
earth I would justifyably be ridiculed. 
"But" I would say " nobody can enumerate all the possible moves and prove 
that none of them perform this transformation. Indeed, there are so many 
moves that it's probable that one of them transforms the cube into a jar of
pickled olives and just imagine the furore if *that* happens!"
When Viruses first appeared on the scene I remember there was some 
speculation that they could occur spontaneously if you tried executing 
areas of memory filled with random numbers. The odds against this are 
inconcievably large. The same thing applies to Tierra except more so.
Interesting and complex behaviour has been observed in evolutionary systems
in the past. However such behaviour was consistent with the environment
the creatures inhabited. it is not possible for Tierra or a distributed 
version of Tierra to breed a legion of Hacking creatures to infest the net.

If however the computer generated environment was taylored to mimic a 
distributed system or if the distributed system itself was used as an 
environment to breed programs to propegate themselves then we would be 
playing an entirely different ball-game. Creatures would need a lot of 
help in the area of what packets to send, what ports to poll and which lines
to monitor etc but I guess that, in an environment expressly taylored to 
evolve hacking creatures, these creatures could evolve.
However using this method to hack would be inefficient for a number of 
reasons which are obvious after some thought.

There is no reason why some distributed Tierra or an equivalent cannot or
shouldnot be produced and used safely. Of course care must be used in the 
coding of such a server for the same reasons as the carefull coding of any
process that has internet access (eg ftpd, httpd, logind etc)

	Rick Heylen

Sysadmin and security adviser to Leeds University Computer Services.
  
