ARPA Whitepaper

Abstract

We propose a secure computation solution for blockchain networks. The correctness of computation is verifiable even under malicious majority condition using information-theoretic Message Authentication Code (MAC), and the privacy is preserved using Secret-Sharing. With state-ofthe-art multiparty computation protocol and a layer2 solution, our privacy-preserving computation guarantees data security on blockchain, cryptographically, while reducing the heavy-lifting computation job to a few nodes. This breakthrough has several implications on the future of decentralized networks. First, secure computation can be used to support Private Smart Contracts, where consensus is reached without exposing the information in the public contract. Second, it enables data to be shared and used in trustless network, without disclosing the raw data during data-at-use, where data ownership and data usage is safely separated. Last but not least, computation and verification processes are separated, which can be perceived as computational sharding, this effectively makes the transaction processing speed linear to the number of participating nodes.Our objective is to deploy our secure computation network as an layer2 solution to any blockchain system. Smart Contracts[41] will be used as bridge to link the blockchain and computation networks. Additionally, they will be used as verifier to ensure that outsourced computation is completed correctly. In order to achieve this, we first develop a general MPC network with advanced features, such as: 1) Secure Computation, 2) Off-chain Computation, 3) Verifiable Computation, and 4)Support dApps' needs like privacy-preserving data exchange.The remainder of this paper is organized as follows: Section 1 introduces the real world motivations which inspired us to build a secure computation network. Following motivations, we highlight our contributions in section 2. We then cover the background of secure computation, along with a comparison of similar technologies. Our system overview is presented in section 4. There, we briefly describe our system design and implementation. In section 5-7, we discuss, in detail, the major components of our multiparty computation protocol, secure computation process, and considerations in cryptoeconomics. Lastly, we review the implications and applications of the real world; this includes ecosystem design, business cases, and milestones.