Newsgroups: comp.arch
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: Software Distribution
Message-ID: <1988Sep9.165744.12634@utzoo.uucp>
Organization: U of Toronto Zoology
References: <891@taux01.UUCP> <28200195@urbsdc> <5655@june.cs.washington.edu> <1076@cs.Buffalo.EDU>
Date: Fri, 9 Sep 88 16:57:44 GMT

In article <1076@cs.Buffalo.EDU> sher@wolf.UUCP (David Sher) writes:
>Out of curiosity since I've not seen this question asked, if the problem
>is that source code is too easy to play with, why not distribute encoded
>source...

Could be done, and I think it is being done by some groups.  It is a
weaker form of protection, though, because you can recover full source
by decrypting, and the compilers have to know how to do that.  Anything
that the compiler knows how to do can, in principle, be analyzed and
duplicated by a sufficiently determined programmer with a disassembler.
Especially if he can then sell his decrypter as a commercial product.
Look at how copy-protection schemes on PCs have fared.

This is especially a problem if we're talking about a vendor-independent
scheme, which of necessity has to be known to many people.

The advantage of the "intermediate"-form approach is that quite a bit of
information is lost during the transformation from source (e.g. one would
presumably lose the spellings of most identifiers), and this information
cannot be recovered just by being clever.
-- 
Intel CPUs are not defective,  |     Henry Spencer at U of Toronto Zoology
they just act that way.        | uunet!attcan!utzoo!henry henry@zoo.toronto.edu
