🔐Cloudflare Builds Post-Quantum Certificate Authority, Cuts Handshake Time 9% in Chrome Test

Your TLS handshakes are about to get lighter

Cloudflare just built a public certificate authority for post-quantum web security, and the trick is getting rid of certificate chains entirely. Its Merkle Tree Certificates batch certificate data into an append-only tree, so clients verify with a compact inclusion proof instead of walking intermediates. Why you should care: post-quantum signatures are about 40 times larger than classical ones. That bloats every handshake. If you run TLS termination, this is the approach that could keep PQ migration from wrecking your bandwidth budget. Servers still have to keep a standalone MTC certificate as a fallback, so don't rip out your current setup yet. The numbers so far: a Chrome experiment showed a 9% faster median, but it used classical signatures, not PQ ones. The handshake now carries one public key, one signature, and an inclusion proof under 1 KB. Landmark relative certificates shave off even more data, and an independent mirroring cosigner keeps the tree honest. What to watch: Cloudflare still needs independent monitoring at production volume, a diverse set of CAs and cosigners, and browser support. Chrome inclusion is targeted for early 2027, and that's when this gets real.