This disclosure relates to secure optical communication links. In particular, this disclosure relates to data storage devices, random access memories, host interfaces, and network layers that comprise a secure optical communication link. A data storage device comprises an optical data port to connect to an optical communication link external to the data storage device and a non-volatile storage medium to store user content data received over the optical communication link. A controller controls access to the user content data stored on the non-volatile storage medium. A cryptography engine uses a cryptographic key to perform cryptographic operations on data sent and received through the optical data port. An optical key distribution device coupled to the optical data port performs quantum key distribution over the optical communication link to provide the cryptographic key to the cryptography engine.