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Path: utzoo!watmath!watnot!watdcsu!rsellens
From: rsellens@watdcsu.UUCP (Rick Sellens - Mech. Eng.)
Newsgroups: net.micro.pc
Subject: Re: what's wrong with this protection?
Message-ID: <1571@watdcsu.UUCP>
Date: Mon, 29-Jul-85 15:51:00 EDT
Article-I.D.: watdcsu.1571
Posted: Mon Jul 29 15:51:00 1985
Date-Received: Wed, 31-Jul-85 01:43:25 EDT
References: <785@aluxe.UUCP>
Reply-To: rsellens@watdcsu.UUCP (Rick Sellens - Mech. Eng.)
Organization: U of Waterloo, Ontario
Lines: 58
Summary: 

In article <785@aluxe.UUCP> wrbull@aluxe.UUCP (bullman) writes:
>I think that instead of wasting their(software companies) money on some
>doo-dad the family Rover will inevitably chew up, they should have put their
>money into developing a small (2 inch maybe) removable optical disc(YES a CD
>ROM!) Transfer rates at winnie rates, cheap(look at your local record store),
>not reproducible(at least not yet!) and relatively immune to environmental
>factors(dogs excluded!). This is so-o-o-o-o obvious that there must be 
>something against really bad about it.
>
>			William R. Bullman
>			AT&T Bell Laboratories
>			Allentown, PA USA
>
>			...!aluxe!wrbull


One major flaw.......

a) What is to prevent you from copying the program from the CD to 
   something else and subsequently executing it on another machine?

b) If you solve (a) through some kludge similar to the usual floppy
   copy protection schemes you have something that:

	- is much more durable than a floppy 
	- costs about 10 times as much (My local supplier can sell
	  me ten floppies for C$13.99; a CD is substantially more
	  even if you discount the royalties to performers.)
	- requires that I puchase a special drive to read it 
	- still requires that I shuffle disks in and out of the
	  drive when I want to use a different piece of software

With these considerations, this scheme strikes me as not worth
the effort.

If you want to follow this tack (I don't particularly), you might
consider a ROM cartridge scheme. All of the newer processors have
humongous addressable memory spaces (68020, 32032, etc.) It should
not be difficult (or as expensive as a CD drive) to include about 
half a dozen ROM cartridge slots in a PC. ( I'm sure I don't use
more than six software packages on a *regular* basis. )

You could then execute your software directly from ROM. Anything
bigger than the cartridge capacity could be provided with only 
part of the program in ROM (some critical routine). The program 
could verify itself by testing that the program counter was pointing
into the ROM area during execution.

This scheme would provide a rugged, easily transferable medium that
cannot be copied nearly as easily as a floppy. You also have something
that is really just a glorified dongle, incorporating the program into
the key. 


Rick Sellens
UUCP:  watmath!watdcsu!rsellens
CSNET: rsellens%watdcsu@waterloo.csnet
ARPA:  rsellens%watdcsu%waterloo.csnet@csnet-relay.arpa