Many blockchain consensus protocols have been proposed recently to scale the throughput of a blockchain with available bandwidth. However, these protocols are becoming increasingly complex, making it more and more difficult to produce proofs of their security guarantees. We propose a novel permissionless blockchain protocol OHIE which explicitly aims for simplicity. OHIE composes as many parallel instances of Bitcoin's original (and simple) backbone protocol as needed to achieve excellent throughput. We formally prove the safety and liveness properties of OHIE. We demonstrate its performance with a prototype implementation and large-scale experiments with up to 50, 000 nodes. In our experiments, OHIE achieves linear scaling with available bandwidth, providing about 4-10Mbps transaction throughput (under 8-20Mbps per-node available bandwidth configurations) and at least about 20x better decentralization over prior works.1 Related observations on Conflux have also been independently made by Bagaria et al. [5] and Fitzi et al. [15].2 Note that the raw available bandwidth is only a rather crude upper bound, and hence in practice it is unlikely for the throughput to reach this upper bound. For example, this crude upper bound does not take into account factors such that TCP slow start, probabilistic block generation, probabilistic hot-spots in the P2P overlay network, overheads for determining which blocks to gossip, and so on.

No abstract

Many blockchain consensus protocols have been proposed recently to scale the throughput of a blockchain with available bandwidth. However, these protocols are becoming increasingly complex, making it more and more difficult to produce proofs of their security guarantees. We propose a novel permissionless blockchain protocol OHIE which explicitly aims for simplicity. OHIE composes as many parallel instances of Bitcoin's original (and simple) backbone protocol as needed to achieve excellent throughput. We formally prove the safety and liveness properties of OHIE. We demonstrate its performance with a prototype implementation and large-scale experiments with up to 50, 000 nodes. In our experiments, OHIE achieves linear scaling with available bandwidth, providing about 4-10Mbps transaction throughput (under 8-20Mbps per-node available bandwidth configurations) and at least about 20x better decentralization over prior works.

No abstract

No abstract