Byzantine consensus is a 40-year old field. Most protocols have been designed in the setting where there is a fixed set of permissioned nodes. The Bitcoin protocol, invented by Nakamoto in 2008, is a breakthrough as it solves the Byzantine consensus problem in a brand new permissionless setting where nodes are free to join and leave the network. However, Bitcoin's throughput is only 7 transactions per second and its confirmation latency is several hours. Previous solutions improve the throughput and latency of Bitcoin by electing a subcommittee of Bitcoin nodes to run a classcal permissioned protocol but this introduces centralization. Prism is the first protocol that provably retains all the decentralization and security properties of Bitcoin while scaling the throughput and latency to physical limits. Experiments on hundreds of EC2 nodes show that Prism achieves throughputs up to 70,000 transactions per second and confirmation latency of $10$'s of seconds. This talk explains the design principles of Prism.
This is joint work with Vivek Bagaria, Sreeram Kannan, Giulia Fanti and Pramod Viswanth.