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From: JOHNC%CAD2.DECnet@GE-CRD.ARPA.UUCP
Newsgroups: mod.computers.vax
Subject: Copy Protection
Message-ID: <8702180018.AA14239@ucbvax.Berkeley.EDU>
Date: Tue, 17-Feb-87 16:50:00 EST
Article-I.D.: ucbvax.8702180018.AA14239
Posted: Tue Feb 17 16:50:00 1987
Date-Received: Wed, 18-Feb-87 22:13:22 EST
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I'd like to add my voice to Mike Porter at U. Delaware (and I hope many others)
to say to the person inquiring about copy protection....  "Please DON'T!"

Copy protection is _always_ a pain in the proverbial to legitimate users, and
_always_ hackable by someone who wants to.  

Mike P had two examples of problems incurred by system managers dealing with
copy protected software.  I'd like to add a third.  

If the protection mechanism depends on CPU id (SID Number) then any ECO 
(engineering change order) affecting the cpu or cpu upgrade (780 -> 785
for example) will invalidate the copy protection becuase it will change
the SID.  Some VAX CPUs have unique SIDs, some don't.  In addition some
CPUs SIDs are partially implemented as DIP switches, furthering the confusion.