RFC 9370

RFC 8784 defines a Postquantum Preshared Key (PPK) method that mixes a static, out-of-band preshared key into the IKE key schedule to defeat 'harvest now, decrypt later' attacks without requiring new …

ML-KEM-768 keys are 25–50× larger than X25519, forcing IKE fragmentation for ML-KEM-768, but its compute cost is comparable to or lower than X25519, adding only about 1 ms to handshake time. The recom…