Blockclique: scaling blockchains through transaction sharding in a multithreaded block graph

Decentralized crypto-currencies based on the blockchain architecture are unable to scale to thousands of transactions per second. We define an architecture, called the blockclique, that addresses this limitation by sharding transactions in a block graph with multiple threads. A block in a given thread only contains transactions with input addresses assigned to this thread, and references one previous block of each thread as parents. When combined with a Proof-of-Stake node selection mechanism, the blockclique architecture reaches 10,000 transactions per second with a transaction time of less than a minute in our simulations, while being robust against known and projected attacks.