On Mon, Nov 04, 2013 at 11:24:33AM -0500, Ittay wrote:
> Yes - this is for the mailing list.
> 
> Regarding the algorithm - as we explain in the paper, as long as the
> attacker is way ahead - the others can mine on whatever they like. Doesn't
> really matter. Once they almost close the gap (and they will, because
> they're the majority), leaving only 1 block lead, the selfish miners
> publish their secret blocks, loose their lead, but win the entire secret
> chain. The honest miners thus loose all the work they did so far. It
> doesn't really matter how the honest miners waste their time.

Yes, they lose their work, but that's irrelevant: what's important is
eventually Alice runs out of secret blocks and then has no advantage
over the other miners.

In your paper Alice created her lead by exploiting the fact that not all
of the hashing power was working to extend the same block due to the
"first-wins" rule. With my solution that situation doesn't happen in the
first place: forks are resolved quickly because both sides have both
forks, and consensus on which one is the winner is achieved very quickly
by proving which side has the majority of hashing power through
near-target PoW solutions. With the majority of hashing power in
consensus and working to extend the same block there's nothing Alice can
do to get ahead, defeating the attack.

-- 
'peter'[:-1]@petertodd.org
0000000000000008adb581077dcfa0bf067a4ee010fbabb92d136292625b2299