During 2020, ITU-T approved a suite of core standards for quantum key distribution networks across Study Groups 13 and 17. Study Group 13 approved Y.3801 (functional requirements, April 2020), Y.3804 (control and management, September 2020), and Y.3802 and Y.3803 (functional architecture and key management, both December 2020). Study Group 17 approved X.1710 (security framework for QKDN) on October 29, 2020, along with X.1702 (quantum noise random number generator architecture) and X.1714 (key combination methods for QKD networks).
X.1710 specified a security framework including threats, requirements, and countermeasures for QKDNs, addressing threats against QKD modules, key management links, control links, management links, and QKD links. Y.3801 defined the functional requirements for QKD networks. Y.3802 specified the functional architecture model with detailed functional elements and interfaces. Y.3803 described key management processes including key generation, storage, relay, synchronization, and supply. Y.3804 addressed QKDN control and management functions.
Together with Y.3800 (approved in October 2019), these standards formed the foundational reference architecture for QKD network standardization at ITU-T. A technical report on security considerations for QKD networks (X.STR-SEC-QKD) was also published in 2020.