Spacemint: A Cryptocurrency Based on Proofs of Space.

摘要: Since its introduction in 2009, Bitcoin has become the most successful cryptocurrency ever deployed. However, currency’s dramatic expansion also raised serious concerns about long-term sustainability: (1) mining dynamics have shifted away from decentralization, as dedicated hardware and entry of governments energy producers gradually placed power hands a select few, (2) network’s growth spurt come with accompanying, vast amounts constantly “wasted” solely for purpose sustaining currency. In this work, we propose SpaceMint, based on proofs space instead wasteful work. Mining SpaceMint is designed to low setup overhead costs, yielding fairer reward structure small large miners. Miners dedicate disk rather than computation. our design, adapt proof-of-space setting, new block chain format transaction types that prevent attacks exploit inexpensiveness (from which alternative non-proof-of-work-based proposals suffered). Our prototype shows initializing 1 TB takes day (a oneoff cost), miners average spend just fraction second per mined. We provide formal game-theoretic analysis modeling ∗In previous version, proposal was called “Spacecoin” “SpaceMint”, but been changed due name conflicts. an extensive game, prove following protocol equilibrium, thereby arguing stability consensus.