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Re: [LUG] BBC IPlayer - A U-Turn ?

 

On Fri, 16 Nov 2007 00:31:28 +0000
"Michael Mortimore" <nospamformike@xxxxxxxxxxxxxx> wrote:

> > You can actually provide DRM stuff using open source code without disclosing
> > how to circumvent it 'at the source code' level. Think GPG keys etc. But like
> > 'closed source' DRM its just not worth the effort.
> surely the program needs to decode the content and if you can modify
> the program (as would be the case with open source) you can send the
> output anywhere you want.

You can already modify the source of gnupg in any way you like but you
won't be able to modify it such that you could decrypt a message
encrypted with the standard program, without the secret key.

DRM isn't that strong but the principle is similar. Any form of
encryption that implements public and private keys means that the
having the source of the program that created the keys is not enough to
crack keys created by the standard program. The problem with DRM is that
the secret key (if any) has to be copied to masses of devices which
makes it less-than-secret.

Like any encryption, once the secret is known, the encryption is
useless (e.g. DVDs). Without the ability to recreate a new secret key
and push it to wherever decryption needs to occur, the entire mechanism
is useless. The only reason that gnupg continues to work is that a new
secret key can be generated - anything made with the old key cannot be
protected.

I encrypt very little nowadays, gnupg is far more useful to prove that
it is really me, via digital signatures. 

-- 

Neil Williams
=============
http://www.data-freedom.org/
http://www.nosoftwarepatents.com/
http://www.linux.codehelp.co.uk/

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