Deconstructing the Blockchain to Approach Physical Limits
This work addresses the fundamental performance bottlenecks in decentralized blockchain systems, offering a significant improvement over existing methods.
The authors tackled the problem of blockchain performance being far from physical network limits by introducing Prism, a new proof-of-work protocol that achieves optimal throughput up to network capacity and confirmation latency proportional to propagation delay with exponentially small error probability.
Transaction throughput, confirmation latency and confirmation reliability are fundamental performance measures of any blockchain system in addition to its security. In a decentralized setting, these measures are limited by two underlying physical network attributes: communication capacity and speed-of-light propagation delay. Existing systems operate far away from these physical limits. In this work we introduce Prism, a new proof-of-work blockchain protocol, which can achieve 1) security against up to 50% adversarial hashing power; 2) optimal throughput up to the capacity C of the network; 3) confirmation latency for honest transactions proportional to the propagation delay D, with confirmation error probability exponentially small in CD ; 4) eventual total ordering of all transactions. Our approach to the design of this protocol is based on deconstructing the blockchain into its basic functionalities and systematically scaling up these functionalities to approach their physical limits.