ChainPKI-Towards Ethash-based Decentralized PKI with Privacy Enhancement

Public key infrastructure (PKI) is the most widely adopted framework aiming to protect the communications between servers and clients, by authenticating users and devices in the digital world. In order to mitigate the single point of failure (SPOF) posed by a centralized PKI architecture, decentralized PKI has received much more attention, which can decentralize the responsibility of certificate authorities. Many blockchain-based PKI systems are developed such as BlockPGP, Blockstack and NoPKI. However, it is found that some existing systems are susceptible to privacy leakage. In this work, we first compare the functionality between blockchain-based PKI systems and analyze the potential privacy issues. Then we focus on Luo's PKI system that adopts the concept of neighborhood and propose a privacy-Aware blockchain-based PKI called ChainPKI, by enhancing the privacy. Our experimental results indicate the effectiveness of our enhanced system auainst notential nrivacv leakaoe,