Description:

We propose a set of changes to the original Bitcoin protocol (called Bitcoin 2) that allows Bitcoin to evolve into a system that is future-proof against developing threats to its original vision -- an alternative, decentralized payment system which allows censorship-resistant, irreversible transactions. Bitcoin 2 strives to be a minimal set that lays the foundations for a long-lived system capable of delivering the original Bitcoin vision, with enough room for growth to layer additional improvements on top of it. These changes include a sliding blockchain with fixed block sizes, the redistribution of dead coins with an unforgeable lottery, enforced mixing, and miner ostracism. The proposed changes require a proactive fork of the original Bitcoin block chain, but they allow final transfers of existing coins into Bitcoin 2 and a reuse of the existing Bitcoin infrastructure.