Re: [Bitcoin-development] The Bitcoin Freeze on Transaction Attack (FRONT)

[Gregory Maxwell <gmaxwell@gmail.com>]

On Tue, Oct 7, 2014 at 7:04 PM, Sergio Lerner <sergiolerner@certimix.com> wrote:
> Using the my previous terminology, automatic fee-sharing ("ORBS") is a
> solution to the freeze problem ("FRONT") but opens the windows to
> "CHAKIDO" double-spending. and CHAKIDO double-spending is a much worse
> problem than FRONT.

I'm not following this. Perhaps I'm getting lost in terminology here.

It's already to provide double spending bounties to greedy-rational
miners, via a simple approach that has been known since at least early
in 2011.    I pay someone then create a later fraudulent doublespend
which is nlocked at the height the original payment occurred, paying
large fees. Then I spend the output of the fraudulent spend nlocked
one block higher, and spend the output of that one again, nlocked one
block higher, and so on... each step paying fees.

A hypothetical purely greedy miner which considers all sequences of
acceptable forks and transactions would see that they have higher
expected returns assisting the theft (assuming the honest party
doesn't fight back by also adopting a similar strategy), at least if
the population of greedy miners is large relative to altruistic ones.

I don't see how miners being able to roll forward fees makes anything
worse, since the transactions themselves can also roll forward fees.