Lecture 18: Fork Consistency, Certificate Transparency

The podcast explores Certificate Transparency (CT), an audit system designed to enhance web security by making certificate issuance public and auditable. It addresses the vulnerabilities of the pre-1995 web, susceptible to man-in-the-middle attacks, and how certificates, SSL, and HTTPS aimed to solve them. However, the proliferation of certificate authorities led to instances of bogus certificates, prompting the need for transparency. CT enforces that all certificates are public, enabling monitors to detect rogue certificates, and uses Merkle trees to ensure log integrity. The discussion covers proofs of inclusion and consistency to prevent deletion and equivocation, and gossip protocols to detect forking. Despite potential issues, CT improves security by ensuring that malicious certificates are eventually detected.