Author: Ethan Heilman 2019-04-19 03:21:53
Published on: 2019-04-19T03:21:53+00:00
The email conversation between Ethan Heilman and ZmnSCPxj revolves around the security concerns related to using Simplified Payment Verification (SPV) in Bitcoin, especially when a chain split occurs. Ethan suggests that in such cases, SPV clients should download and validate the "longest chain" up to more than one block greater than the height of the losing chain. However, ZmnSCPxj points out that if a miner with >33% of network hashrate creates multiple 1-block chainsplits, it can disrupt SPV clients and force them to download every block, making them full nodes anyway.Furthermore, the discussion on the bitcoin-dev mailing list is centered around the potential for a minority miner to disrupt the SPV-using network. If an invalid block is created and only 10% of the miners are honest, it would take an average of 100 minutes for a valid block to appear. During this time, the SPV client would be following the invalid chain and see roughly 9 confirmations before the chain gets rejected. One participant raises the concern that a minority miner could deliberately ignore every other valid block and create a valid block at N+1, disrupting the SPV-using network if it has more than 10% of the network hashrate. This rule of thumb would give it the ability to disrupt the network on average. It is noted that 10% of network hashrate to disrupt SPV-using nodes would be a low bar to disruption, as without this rule, disruption would require over 50% network hashrate. The discussion concludes with the reminder that every rule imposed creates a potential loophole for a new attack, and caution should be exercised when implementing rules.In conclusion, the best case outcome to prevent malicious attacks on SPV clients is to have them slow down or become full nodes when a miner with significant mining power attempts to disrupt the network. The discussion highlights the need for caution and careful consideration of potential loopholes when implementing rules to prevent attacks on the Bitcoin network.
Updated on: 2023-06-13T18:17:54.118152+00:00