Leveraging Blockchain Technology for a Decentralized Public Key Infrastructure: A Blueprint for Secure Digital Identity Management

The current centralized model of Public Key Infrastructure (PKI) relies heavily on trusted Certificate Authorities (CAs) to authenticate digital identities. Still, this system faces significant security risks, including fraudulent certificate issuance and CA compromises. This thesis explores the potential of blockchain technology as a decentralized solution to these issues, proposing a distributed PKI framework that removes the single point of failure inherent in traditional systems. By leveraging blockchain’s immutability, consensus protocols, and transparency, this approach aims to enhance digital identity security and offer a more resilient infrastructure for managing certificates. A novel design is presented, incorporating a twophase Proof of Stake consensus mechanism, an account tree for domain owners’ public keys, and advanced certificate extensions for verifying identities within the blockchain network. The proposed framework not only improves the security of certificate issuance but also ensures tamper-proof logging and decentralized control, reducing the risks associated with CA vulnerabilities. This research lays the foundation for a more robust, scalable, and censorship-resistant PKI, providing an innovative solution to the challenges facing modern digital communications.