Author: Gregory Maxwell 2014-10-05 23:40:43
Published on: 2014-10-05T23:40:43+00:00
In an email conversation on October 5, 2014, Sergio Lerner shared a vulnerability in the Bitcoin protocol that could affect its future. He called it "The Freeze on Transaction Problem." To address this problem, some tools were discussed in the past that could be helpful. The first tool is the use of locktime on normal transactions, which is already in Bitcoin core git. This means users can locktime their transaction at a high point where they expect it to get included. If used well, it creates a base of fees that can only be collected by future blocks, creating an incentive to move forward. The second tool is having block commitments in transactions, where the data under signature in a transaction could commit to some recent block that must be in the chain, or the transaction's fee cannot be collected. This allows transacting users to vote with their fees on the honest chain and complicates strategy for forking miners as future transactions may have fees conditional on the honest chain. However, these tools do not completely address the concern.The third tool is fee forwarding, where miners get half the fees, and the rest are added to a pool that pays out half in every successive block. This prevents unusually high fees from making much reorg pressure and correctly models what people would like to pay for. However, miners can demand users pay fees out of band, and there are complexities regarding adjusting the difficulty of creating a block slightly.Sergio suggested formalizing the analysis of the proportion of the network that is rational versus honest or altruistic. If there is a significant amount of honest hash rate refusing to aid greedy behavior, even at a potential loss to themselves, then the strategy becomes a loser for purely greedy participants. It would be interesting to characterize the income tradeoffs for different amounts of altruism and any convergence problems that an attempt by altruistic participants to punish the forkers might create.
Updated on: 2023-05-19T19:21:37.252056+00:00