Cryptography Research wants piracy speed bump on HD DVDs

[Ian G]

Adam Back wrote:

>>From what I recall from reading the CR paper a while back they can
>tolerate up to some threshold of colluding players.  However if you go
>over that threshold (and it's not too large) you can remove the mark.
>
>I would think the simplest canonical counter-attack would be to make a
>p2p app that compares diffs in the binary output (efficiently rsync
>style) accumulates enough bits to strip the disk watermark, p2p rips
>and publishes.  QED.
>  
>
If the p2p apps could collude, they could create
a pre-threshold image and share it amongst
themselves only, gradually combining it until
no more differences were detected.  When a
post threshold watermark was reached, the
final image could be released.  You would need
some way to know that the watermark had
been reached, according to the testing against
a sufficient sized pool or somesuch metric.

Add some reputation nyms to sign and that
should avoid the poisoning attacks as well.

-- 
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