Google Brings Quantum-Hardened HTTPS To Chrome In Major Security Upgrade

Traditional cryptographic signatures that underpin HTTPS can be broken by a sufficiently powerful quantum computer using algorithms like Shor's, threatening the trust model of secure connections. To help protect against this threat, Google is rolling out a major upgrade to Secure HTTP in its Chrome browser. In a blog post published yesterday, the Chrome Secure Web and Networking Team outlined a new program to make TLS certificates resistant to future quantum attacks without imposing significant performance penalties on the web ecosystem.

The central innovation in Google's approach is the adoption of Merkle Tree Certificates (MTCs), a structure that replaces the long chain of signatures found in classic X.509 certificates with compact proofs that a given certificate is included in a public Merkle tree. Under this model, a Certification Authority signs a single "Tree Head" representing "potentially millions of certificates," and the browser verifies inclusion using a lightweight ...