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Title: Prism: Deconstructing the Blockchain to Approach Physical Limits
The concept of a blockchain was invented by Satoshi Nakamoto to maintain a distributed ledger. In addition to its security, important performance measures of a blockchain protocol are its transaction throughput and confirmation latency. In a decentralized setting, these measures are limited by two underlying physical network attributes: communication capacity and speed-of-light propagation delay. 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 the bandwidth-delay product CD; 4) eventual total ordering of all transactions. Our approach to the design of this protocol is based on deconstructing Nakamoto’s blockchain into its basic functionalities and systematically scaling up these functionalities to approach their physical limits.
Authors:
; ; ; ;
Award ID(s):
1651236 1718270
Publication Date:
NSF-PAR ID:
10145955
Journal Name:
ACM SIGSAC Conference on Computer and Communications Security
Page Range or eLocation-ID:
585 to 602
Sponsoring Org:
National Science Foundation
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