

Proof of Computational Work - gubatron
http://www.kapsi.de/blog/index.php/2011/07/proof-of-computational-work/

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natch
Ah yes, another person new on the Internet. Welcome. The blogger doesn't seem
to be aware that this is an old idea, dating back to 1992 or earlier (well
before the also old 1997 date given in WikiPedia for HashCash). See the
references in this paper: <http://www.cl.cam.ac.uk/~rnc1/proofwork.pdf>

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drfuchs
The original "Pricing Via Processing or Combatting Junk Mail" paper by Dwork &
Naor from 1992 is
[http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.75....](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.75.798&rep=rep1&type=pdf)

And the follow-on "On Memory-Bound Functions for Fighting Spam" (which is
based on the notion that "since memory access speeds vary across machines much
less than do CPU speeds, memory-bound functions may behave more equitably than
CPU-bound functions") is:
[http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.85....](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.85.9764&rep=rep1&type=pdf)

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hollerith
>A novel idea to fight Spam in Distributed Systems with no or minimum State.

It is not novel. It has been discussed extensively in the context of email
spam.

