ML-KEM is NIST’s standardized post-quantum key-establishment scheme, derived from the CRYSTALS-Kyber design. The name stands for Module-Lattice-Based Key-Encapsulation Mechanism. It is used to establish shared secret keys, not to encrypt bulk data directly. In practice, a client and server use ML-KEM to agree on a session key that can then protect traffic or stored data with symmetric encryption.
Its security value is that it is designed to resist attacks from large quantum computers, which are expected to weaken widely used public-key systems such as RSA and elliptic-curve cryptography. Defenders use ML-KEM in hybrid TLS, VPNs, secure messaging, and cloud services to reduce long-term exposure of encrypted data. The main risks are implementation bugs, weak randomness, and side-channel leaks, so “post-quantum” should be understood as a cryptographic property, not a complete security guarantee.