Microsoft publicly announces Penny Black PoW postage project

[Jim Gillogly]

Steve Schear wrote:

> http://news.bbc.co.uk/2/hi/technology/3324883.stm

Rather than proving that you've wasted a signficant amount of computing
resources, wouldn't it be preferable to prove that you've contributed
the same amount of power to a useful compute-bound project, such as
NFSNET.org or GIMPS or Folding at home or SETI at home?  It would require some
change on the qualifying cycle charities to issue "stamps": the spammer
or sender would send the cycle charity a hash of the message and the
completed assignment, and the charity would return a signature for the
message.  The receiver would pay only to verify the signature, including
the date and whatever headers are necessary for personalization.  Perhaps
something easy could deal with replay, but even without this addition
it's easier to deal with identical spams than random ones -- I suppose
one's mailer could keep track of the last few hashes it's accepted if
this turns out to be an issue.

It's more work for a cycle sink to become a recognized mail certifier,
but worth it -- in exchange for the signature mechanisms they get more
(potentially a lot more) contributors.
-- 
	Jim Gillogly

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