We need to fix the block withholding attack

Summary:

The discussion on bitcoin-dev mailing list revolves around the possibility of block withholding attacks and ways to prevent them. Some suggest that there are techniques that can be used to detect such attacks, but they are not revealed due to concerns of avoidance by attackers. Vigilante attackers who want to hurt only large pools may face issues in identifying which ones are too large as multiple small pools could masquerade themselves as a single large pool. However, it is noted that an attacker attacking all parts of the open pool proportionally to their size results in an identical outcome to that of attacking a single large pool.The conversation also touches on the idea of large, well-resourced pools using KYC and DRM tech to prevent block withholding attacks, which would not be a positive development for the ecosystem. While some believe that every open pool would implement identity checking, others think that the bigger pools will become more suspicious of signing up new hash power and small groups of people who have some reason for trusting each other will band together into small pools, leading to fantastic outcomes for decentralization. The tech behind DRM called "attestation" provides technical capability not possible by any other means and can ensure that a remote node is indeed running the code that it purports to be running. It is mentioned that yelling at large open pools will not scale and better mechanisms are needed for keeping pools in check. Miner's Dilemma (MD) attacks are deemed quite effective, and the loss of the biggest open pools would not be a bad outcome. Suggestions like having the pool pick a secret k for each share and committing to H(k) in the share require a change to the Bitcoin PoW, which is not easy to achieve. Overall, the conversation highlights the need for more robust measures to prevent block withholding attacks while ensuring a decentralized ecosystem.

Updated on: 2023-06-11T02:27:47.435969+00:00