US 11,750,379 B2
Secure optical communication link
Daniel Bedau, San Jose, CA (US)
Assigned to Western Digital Technologies, Inc., San Jose, CA (US)
Filed by Western Digital Technologies, Inc., San Jose, CA (US)
Filed on Jun. 11, 2020, as Appl. No. 16/899,536.
Prior Publication US 2021/0391988 A1, Dec. 16, 2021
Int. Cl. H04L 9/08 (2006.01); H04B 10/27 (2013.01); G06F 13/42 (2006.01); G06F 21/60 (2013.01)
CPC H04L 9/0858 (2013.01) [G06F 13/4282 (2013.01); G06F 21/602 (2013.01); H04B 10/27 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A data storage device comprising:
an optical data port configured to connect to an optical communication link external to the data storage device;
a non-volatile storage medium configured to store user content data received over the optical communication link;
a cryptography engine configured to use a cryptographic key to perform cryptographic operations comprising encrypting and decrypting data sent and received through the optical data port;
an optical key distribution device coupled to the optical data port and configured to perform quantum key distribution over the optical communication link; and
a controller configured to:
perform a protocol stack for managing storage commands received as digital data through the optical communication link to a host;
execute operations for quantum key distribution using digital data messages at a top layer of the protocol stack, wherein the operations for quantum key distribution include receiving a discovery message from the host indicating key exchange capability; and
initiate, responsive to receiving the discovery message and using the optical key distribution device, quantum key distribution through a physical layer of the optical communication link to the host, wherein:
the cryptography engine is further configured to receive the cryptographic key based on the quantum key distribution; and
initiating quantum key distribution includes switching the optical key distribution device to use the physical layer of the optical communication link to transmit quantum information for determining the cryptographic key.