# ARPA Whitepaper

## TL;DR

This paper presents a secure, privacy-preserving computation layer for blockchain networks that ensures correctness under malicious conditions, supports private smart contracts, and enhances scalability by separating computation and verification.

## Contribution

It introduces a novel layer2 solution using advanced multiparty computation and cryptographic techniques to enable secure, verifiable, and efficient off-chain computations on blockchain.

## Key findings

- Verifiable correctness under malicious majority using information-theoretic MAC.
- Supports private smart contracts with privacy-preserving data exchange.
- Achieves linear transaction processing speed with computational sharding.

## 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-of-the-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\cite{smartcontract} 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.