Author: Sergio Lerner 2014-04-28 14:32:33
Published on: 2014-04-28T14:32:33+00:00
The conversation between Mark Friedenbach and Sergio Lerner centers on the security assumptions of Simplified Payment Verification (SPV) nodes. The main issue is that SPV nodes trust that the most-work chain is a valid chain, based on economic arguments about the opportunity cost of mining invalid blocks. However, this assumption may not hold during an attack when someone gives you a fake block, and you lose the possibility to reach any honest node. In SmartSPV, the security assumptions are weaker, requiring that the attacker cannot control all your communications with the payment network for more than a fixed period of time and is rational. While NPPs use synchronized peers to choose the common ancestor, the linear scan is actually O(1). However, if one is connected to attacker nodes that are wildly divergent from each other, it is easy to create a massive fake history of difficulty-1 blocks. In contrast, back-link block-history commitments allow you to do a binary search to find common ancestors, and have trust that the intermediate links actually exist.
Updated on: 2023-06-08T21:47:40.005235+00:00