DAON: A Decentralized Autonomous Oracle Network to Provide Secure Data for Smart Contracts

Blockchain, which originated with the Bitcoin system, has drawn intense attention because of its decentralization, persistence, and anonymity. The execution environment of blockchain is isolated from the external world and requires “blockchain oracles”: agents that fetch information from the outside world. However, there is always the risk of oracles providing corrupt, malicious, or inaccurate data. To overcome this issue, this paper analyses the existing oracle working patterns, then introduces a decentralized autonomous oracle network (DAON) and its consensus protocol and noninteractive reputation maintenance and payment scheme. Meanwhile, the reputation and security monitoring services of DAON are designed to ensure the DAON provide trustworthy data services in a complex byzantine environment. The proposed method is verified by experiments on three applications. Using the proposed network, smart contracts on future blockchains could have reliable, tamper-proof inputs and outputs.