{
  "id": 19166749,
  "title": "Cloudflare Develops Public Certificate Authority for Post-Quantum Web Security",
  "url": "https://urgent.news/2026/11/09/cloudflare-develops-public-certificate-authority-for-post-quantum-web",
  "topic": "tech",
  "section": "Tech",
  "published": "2026-11-09T14:35:00.000Z",
  "source": {
    "name": "InfoQ",
    "slug": "infoq",
    "url": "https://www.infoq.com/news/2026/11/cloudflare-merkle-certificates/"
  },
  "original_language": "en",
  "account": "Cloudflare has developed a public Certificate Authority (CA) for post-quantum web security using Merkle Tree Certificates (MTCs). In a Chrome experiment, MTCs proved 9% faster than traditional certificate chains. This method groups certificate data into an append-only Merkle tree, allowing clients to verify certificates with compact inclusion proofs instead of full certificate chains. The experiment used classical signatures but laid the groundwork for future post-quantum signatures. Further improvements include landmark-based verification and independent transparency log cosigners, which support certificate issuance and verification at scale. Cloudflare tested billions of MTCs with 50% of Chrome Beta 146 on their free plan, with the experiment concluding in August 2026. The company plans to develop a public MTC-supporting CA for inclusion in Chrome's quantum-resistant Root Store in early 2027, pending evaluation. Cloudflare CEO Matthew Prince highlighted the challenge of upgrading web security before quantum computers can break it, emphasizing the scaling challenges of post-quantum cryptography. MTCs merge certificate issuance with transparency logging, reducing the need to sign certificates individually. Instead, a CA records certificate data in an append-only Merkle tree and signs a checkpoint. Clients verify certificate inclusion using cryptographic proofs. Cloudflare employs the Automated Certificate Management Environment (ACME) protocol for domain ownership validation, and an independent mirroring cosigner verifies and stores updated tree states. Landmark relative certificates further minimize TLS handshake data, with authenticated landmarks distributed to clients for verification. However, challenges remain regarding revocation, incident handling, and broader deployment requirements such as independent monitoring, diverse CAs and cosigners, and browser support.",
  "summary": "Cloudflare is developing a public certificate authority for Merkle Tree Certificates (MTCs) to reduce the bandwidth overhead of post-quantum cryptography. A Chrome experiment served billions of MTCs to 50% of Chrome Beta 146 for selected domains, reporting 9% faster median performance. Wider deployment depends on browser support, transparency, and production-scale validation. By Leela Kumili",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}