Connecting Blockchains to the Real World
Smart contracts are applications that execute on blockchains. Their strong security properties (transparency, tamper-resistance, and censorship-resistance) have attracted significant attention and investment ($31B thus far via ICOs), but most of their real-world uses, such as tokens, exercise little of smart contract's potential power. A key reason is a disconnection from the real world: There is currently no secure, decentralized way to faithfully convey real-world states to blockchains (or any distributed systems). Worse yet, smart contracts inherit blockchains' lack of confidentiality and poor performance.
My research in applied cryptography and system security aims to change this situation. In this talk, I'll start with my work on data oracles that enable the faithful representation of real-world states on blockchains. I'll present Town Crier and DECO, two systems that can convert widely deployed TLS-enabled data sources to authenticated data feeds. Then I'll present Ekiden, a system that endows smart contracts with privacy by storing secrets and performing computation in off-chain committees. Much of the work I'll present has seen industry uptake. Finally, I'll discuss future plans for leveraging systems I developed to enable secure systems that empower and protect their users from insecure and centralized infrastructure.
Fan Zhang is a Ph.D. candidate in Computer Science at Cornell University, advised by Prof. Ari Juels. His research interest is in building secure systems that empower and protect their users from insecure and centralized infrastructure, by leveraging cryptography, blockchains, and trusted execution environments (TEEs). His Ph.D. thesis focuses on a principled composition of on-chain and off-chain components to enable provably secure, efficient, and decentralized systems. His works have been featured in Forbes, MIT Tech Review, IEEE Spectrum, CoinDesk, BitcoinMagazine, and numerous blockchain news outlets. Several of his works have been adopted by industry and deployed in the wild. He is a member of IC3 and a recipient of an IBM Ph.D. Fellowship for 2018-2020. Before joining Cornell, he received his Bachelor's degree from Tsinghua University.