Blockchain-Based Public Key Infrastructure Using Smart Contracts

Abstract

Certificate authorities are a massive point of weakness in traditional PKI. Blockchain technology offers an easy way to implement Certificate Transparency but existing blockchain-based PKIs lack either support for key updates, revocations, or privacy. This paper explores two existing solutions and merges their ideas to provide all of the aforementioned properties. The proposed system provides a Public Key Infrastructure based on Ethereum that supports traditional key registration and revocation, while also facilitating anonymous key updates. These key updates are chained from initial key registrations, allowing subjects to disclose their newest key on their discretion.