Author: Luke-Jr 2013-07-14 20:16:41
Published on: 2013-07-14T20:16:41+00:00
In a discussion about the issue of mining invalid blocks in merge-mined coins, Pieter Wuille brings up the concern that unless there is a cost to mining an invalid block, the merge-mined coin has little protection from miners who mine invalid blocks either maliciously or through negligence. Luke-Jr argues that invalid blocks are rejected by validating clients in all circumstances, but Wuille clarifies that this is not what John meant. The issue is that if a miner has hash power for the parent chain, mining invalid blocks for the merge-mined chain costs them nothing. This means that the "lesser" chain may not be able to trust Simplified Payment Verification (SPV), but trusting SPV was already a bad idea anyway.Wuille notes that merged mining is pretty much unavoidable in any case, and the basic assumption underlying mining security is that it is more profitable to collaborate with mining a chain than to attack it. However, in the case of merged mining, this assumption is not valid. The basic assumption of SPV is that more people will be assisting rather than making invalid blocks, and proper validating clients do not rely on an economic motive. The only real assumption behind mining is that the majority will not aim to reverse transactions with valid blocks.As an aside, Wuille suggests the idea of a Zerocoin with no-reward/PoSacrifice merged mining as well as (rewarded) Prime POW, without subsidy halving, to try a new economic idea.
Updated on: 2023-06-06T19:47:13.571466+00:00