Post-quantum IPsec interoperability with third-party devices
Cloudflare IPsec now supports post-quantum key agreement with compatible third-party devices, including Cisco and Fortinet routers. The implementation uses ML-KEM hybrid key exchange combined with classical Diffie-Hellman to protect against harvest-now, decrypt-later attacks.
Cloudflare IPsec now supports post-quantum key agreement with compatible third-party devices. Cisco ↗ and Fortinet ↗ are the first third-party vendors validated to interoperate with Cloudflare IPsec using ML-KEM (Module-Lattice-Based Key-Encapsulation Mechanism).
Post-quantum IPsec uses RFC 9370 ↗ and draft-ietf-ipsecme-ikev2-mlkem ↗ to negotiate hybrid key agreement during the IKEv2 IKE_INTERMEDIATE phase. This combines classical Diffie-Hellman (Group 20) with ML-KEM-768 or ML-KEM-1024 to protect against harvest-now, decrypt-later ↗ attacks.
Key details:
- Compatible with Cisco 8000 Series Secure Routers with IOS XR Release 26.1.1 and Fortinet FortiOS 7.6.6 and later.
- Uses ML-KEM-768 or ML-KEM-1024 as an additional Key Exchange to DH Group 20.
- Follows RFC 9370 and draft-ietf-ipsecme-ikev2-mlkem standards.
- No additional licensing required.
Post-quantum IPsec with third-party devices is now generally available with confirmed interoperability for the platforms listed above. Cloudflare intends to support interoperability with more vendors as they build out support for draft-ietf-ipsecme-ikev2-mlkem. Contact your account team to discuss support for additional vendors.
For supported key exchange methods and the list of validated platforms, refer to GRE and IPsec tunnels.
Source: original entry ↗
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