Re: [Bitcoin-development] A statistical consensus rule for reducing 0-conf double-spend risk

2014-05-12 Thread Tom Harding
Sorry to run on, a correction is needed. A much better approximation requires that the rule-following minority finds the next TWO blocks, so the cost is (total miner revenue of block)*(fraction of hashpower following the rule)^2 So the lower bound cost in this very pessimistic scenario is

Re: [Bitcoin-development] A statistical consensus rule for reducing 0-conf double-spend risk

2014-05-06 Thread Tom Harding
Christophe Biocca wrote: it becomes trivial with a few tries to split the network into two halves: (tx1 before tx2, tx2 before tx1). before implies T=0. That is a much too optimistic choice for T; 50% of nodes would misidentify the respend. Tom Harding t...@thinlink.com wrote: -

Re: [Bitcoin-development] A statistical consensus rule for reducing 0-conf double-spend risk

2014-05-03 Thread Christophe Biocca
Unfortunately this could fork the network permanently, which is much worse than a double spend. There's no magic way to have a consensus, so it becomes trivial with a few tries to split the network into two halves: (tx1 before tx2, tx2 before tx1). Some nodes in the middle will accept either