Author: Kevin 2014-04-23 15:34:39
Published on: 2014-04-23T15:34:39+00:00
On the Bitcoin-development mailing list, Mike Hearn discusses the issue of Finney attacks, where a miner secretly works on a block containing a double spend, and proposes a solution to discourage blocks that perform such attacks. He suggests having honest miners refuse to build on them, but acknowledges that this has some problems, including the difficulty in automatically detecting Finney attacks and the possibility of converting it into a DoS on the network. He proposes a solution that involves identifying dishonest blocks out of band by having honest miners submit double spends against themselves anonymously using a separate tool, and allowing miners to vote to reallocate the coinbase value of bad blocks before they mature. This approach only applies to coinbases, not arbitrary transactions, thus it cannot be used to steal arbitrary users bitcoins. The identification of Finney blocks relies on miners taking explicit action, like downloading and running a tool that submits votes via RPC. It can be expected that double spending services would try to identify and block the sentinel transactions, which is why it's better to have the code that fights this arms race be out of process and developed externally to Bitcoin Core itself.
Updated on: 2023-06-08T20:49:55.841813+00:00