Liaison statement
LS on work progress on Quantum Key Distribution (QKD) network in SG13 (as of July 2023)

ITU-T SG13 Working Parties 1/13 and 3/13 are pleased to inform you of our
progress on Quantum Key Distribution (QKD) topics.

SG13 has published 15 Recommendations and 3 Supplements on QKDN as follows:
- Recommendation ITU-T Y.3800 “Overview on networks supporting quantum key
distribution”; - Recommendation ITU-T Y.3801 “Functional requirements for
quantum key distribution networks”; - Recommendation ITU-T Y.3802 “Quantum key
distribution networks – Functional architecture”; - Recommendation ITU-T Y.3803
“Quantum key distribution networks – Key management”; - Recommendation ITU-T
Y.3804 “Quantum key distribution networks - Control and management”; -
Recommendation ITU-T Y.3805 “Quantum Key Distribution Networks - Software
Defined Networking Control”; - Recommendation ITU-T Y.3806 “Quantum key
distribution networks - Requirements for quality of service assurance”; -
Recommendation ITU-T Y.3807 “Quantum Key Distribution networks - QoS
parameters”; - Recommendation ITU-T Y.3808 “Framework for integration of
quantum key distribution network and secure storage network”; - Recommendation
ITU-T Y.3809 “A role-based model in quantum key distribution networks
deployment”; - Recommendation ITU-T Y.3810 “Quantum key distribution network
interworking - Framework”; - Recommendation ITU-T Y.3811 “Quantum key
distribution networks - Functional architecture for quality of service
assurance”; - Recommendation ITU-T Y.3812 “Quantum key distribution networks -
Requirements for machine learning based quality of service assurance”; -
Recommendation ITU-T Y.3813 “Quantum key distribution networks interworking –
functional requirements”; - Recommendation ITU-T Y.3814 “Quantum key
distribution networks - functional requirements and architecture for machine
learning enablement”; - Supplement ITU-T Y.Sup70 to Y.3800-series “Quantum Key
Distribution Networks - Applications of Machine Learning”; - Supplement ITU-T
Y.Sup74 to Y.3000-series “Standardization roadmap on Quantum Key Distribution
Networks”; - Supplement ITU-T Y.Sup75 to Y.3800-series “Quantum key
distribution networks - Quantum-Enabled Future Networks”.

1. The Recommendations consented at the July 2023 WP1/13 and WP3/13 meetings

The draft Recommendations ITU-T Y.3818 (Y.QKDN-iwac), Y.3815 (Y.QKDN-rsfr),
Y.3816 (Y.QKDN-qos-ml-fa), and Y.3817 (Y.QKDN-qos-iw-req) were consented.

Recommendation ITU-T Y.3818 (Y.QKDN-iwac) “Quantum key distribution networks
interworking - architecture” in TD300/WP3

For quantum key distribution networks (QKDN), Recommendation ITU-T Y.QKDN_iwac
specifies functional architecture for QKDNi.

Recommendation ITU-T Y.3815 (Y.QKDN-rsfr) “Quantum key distribution networks –
overview of resilience” in TD301/WP3

For quantum key distribution network (QKDN), this recommendation describes an
overview of QKDN resilience with models of QKDN protection and recovery.

Recommendation ITU-T Y.3816 (ex. Y.QKDN-qos-ml-fa) “Quantum key distribution
networks – Functional architecture enhancement of machine learning based
quality of service assurance” in TD461/WP1

For quantum key distribution network (QKDN), this recommendation describes
functional architecture enhancement of machine learning based quality of
service assurance.

Recommendation ITU-T Y.3817 (ex. Y.QKDN-qos-iw-req) “Quantum key distribution
networks interworking – requirements for quality of service assurance” in
TD463/WP1 For quantum key distribution network (QKDN), this recommendation
describes requirements for quality of service assurance in QKDNi.

2.Revised on-going work items after March 2023 SG13 meeting

Draft Recommendation ITU-T Y.QKDNi_SDNC “Quantum Key Distribution Network
Interworking – Software Defined Networking Control” in TD304/WP3

This draft Recommendation specifies the Software Defined Network control for
the interworking including the overview of the role of SDN control for the
interworking between QKDN providers, the functional entities of SDN control for
the interworking, the interfaces of SDN control for the interworking, the
functional requirements of SDN control for the interworking, and the security
considerations.

Draft Recommendation ITU-T Y.QKDNf_fr “Framework of Quantum Key Distribution
Network Federation” in TD305/WP3

This draft Recommendation specifies the framework of Quantum Key Distribution
Network Federation (QKDNf) including the overview of QKDNf, reference
architecture for enabling QKDNf, functional entities of QKDNf, reference points
for the QKDNf, functional requirements of the QKDNf, overall operational
procedures of QKDNf and security considerations.

Draft Recommendation ITU-T Y.QKDN-AMC “Quantum key distribution networks -
Requirements and architectural model for autonomic management and control" in
TD306/WP3

Autonomic Management and Control (AMC) is about Decision-making-Elements (DEs)
as autonomic functions (i.e. control-loops) with cognition introduced in the
management layer as well as in the control layer. Cognition in DEs, enhances DE
logic and enables DEs to manage and handle even the unforeseen situations and
events detected in the environment around the DE(s). As the number and
diversity of devices that make up the individual QKDNs continue to grow,
automating QKDN control and management tasks becomes ever-more important to
improve the quality of services (QoS).

To cope with the challenges of QKDN control and management, while minimizing
human intervention towards full automation of QKDN, this draft Recommendation
specifies the requirements and architectural models for AMC in QKDNs including
the overview, requirements, consideration for cognition process and
architectural model.

Draft Technical Report ITU-T TR-QN-UC “Use cases of quantum networks beyond
QKDN” in TD307/WP3 Based on the deliverable (D1.2) of the ITU-T Focus Group on
Quantum Information Technology for Networks (FG QIT4N), this Technical Report
sorts and analyses use cases of quantum networks beyond QKDN collected from FG
QIT4N in the context of networking technologies as the mandate of ITU-T SG13.

The uses cases which are only applied by quantum networks beyond QKDN are
collected, investigated and summarized; all use cases are analysed by current
bottlenecks, application scenarios, technical requirements and solutions. This
Technical Report also provides analyses for future applications and potential
standardization requirements.

Draft Supplement ITU-T Y.supp.QKDN-UC “Use cases of quantum key distribution
networks” in TD308/WP3

Based on the deliverable (D2.2) of the ITU-T Focus Group on Quantum Information
Technology for Networks (FG QIT4N), this Supplement consolidates the QKDN use
cases collected from the ITU-T FG QIT4N in the context of networking
technologies as the mandate of ITU-T SG13.

Through a comprehensive analysis, the QKDN uses cases are classified into
several classes and this Supplement highlights the competitive advantage of the
use cases brought by QKDN and provides suggestions for future standardization
efforts in ITU-T SG13.

Draft Recommendation ITU-T Y.QKDN-TSNfr “Framework for integration of quantum
key distribution network and time sensitive network " in TD310/WP3

This Recommendation specifies the framework for integration of quantum key
distribution network (QKDN) and time sensitive network (TSN) including the
overview and scenarios of QKDN and TSN integration, the network capabilities to
support QKDN and TSN integration, the conceptual structure and basic functions
of QKDN and TSN integration, and its overall operational procedures and
security considerations.

Draft Recommendation ITU-T Y.QKDN-rsrq “Requirements for quantum key
distribution network resilience” in TD309/WP3

For quantum key distribution networks (QKDN), Recommendation ITU-T Y.QKDN-rsrq
specifies the general requirements for resilience, and separately specifies the
supporting requirements for protection and recovery.

Draft Technical Report on "Overview for integration of quantum key distribution
network with non-quantum cryptographies” in TD311/WP3

This report provides the overview for integration of quantum key distribution
network with non-quantum cryptographies under three categories as follows:

- QKDN’s relation to end-to-end cryptography service
- Service Scenarios for the integration with non-quantum cryptography (e.g.,
PKI architecture) - Implications for standardization activity on Study Group 13

3. New work items agreed at the July 2023 WP3/13 meeting
Proposed amendments to ITU-T Y.3802: “Functional architecture of quantum key
distribution” in TD316/WP3

This WI will develop an amendment to Y.3802 as follows;
- to add a reference point of Mx in clause 8.4 Reference points on a QKDN
manager; - to revise Figure 1 – A functional architecture model of QKDN in
clause 6 Functional architecture model to include the Mx reference point and an
editorial correction on key relay. Proposed amendments to ITU-T Y.3803:
“Quantum key distribution networks – Key management” in TD317/WP3

This WI will develop an amendment to Y.3803 as follows;
- to revise Figure 2 of Y.3803 – A functional architecture model of QKDN in
clause 7 Functional elements of key management to include the Mx reference
point and an editorial correction on key relay.

Proposed amendments to ITU-T Y.3804: “Quantum key distribution networks –
Control and management” in TD318/WP3

This WI will develop an amendment to Y.3804 as follows;
- to add a reference point of Mx in clause 8.4 Reference points on a QKDN
manager; - to revise Figure 1 – A functional architecture model of QKDN in
clause 6 Functional architecture model to include the Mx reference point and an
editorial correction on key relay.

Proposed amendments to ITU-T Y.3805: “Quantum key distribution networks –
Software-defined networking control” in TD319/WP3

This WI will develop an amendment to Y.3802 as follows;
- to revise Figure 1 of Y.3805 – Functional architecture for SDN control in
QKDN in clause 8 Functional architecture for SDN control in QKDN to include the
Mx reference point and an editorial correction on key relay.

Proposed amendments to ITU-T Y.3811: “Quantum key distribution networks –
Functional architecture for quality of service assurance” in TD320/WP3

This WI will develop an amendment to Y.3811 as follows;
- to revise Figure 1 – Functional architecture of QoS assurance for QKDN to
include the Mx reference point and editorial corrections.

Proposed amendments to ITU-T Y.3814: “Quantum key distribution networks –
Functional requirements and architecture for machine learning enablement” in
TD321/WP3

This WI will develop an amendment to Y.3814 as follows;
- to revise Figure 8-1 – Functional architecture model of QKDNml to include the
Mx reference point and an editorial correction.

4. Conclusion

SG13 will study the network aspects of QKD. Q16/13 and Q6/13 look forward to
close cooperation with ITU-T SG2, SG11, SG15, SG17, ETSI ISG-QKD, ISO/IEC
JTC1/SC27, WG14, AG4, IETF/IRTF, and relevant groups for future standardization
on QKD networks.

Attachments:
1) The consented draft Recommendation ITU-T Y.3818 (ex Y.QKDN-iwac) “Quantum
key distribution networks interworking - architecture” (TD300/WP3); 2) The
consented draft Recommendation ITU-T Y.3815 (ex Y.QKDN-rsfr) “Quantum key
distribution networks – overview of resilience” (TD301/WP3); 3) The updated
draft Recommendation ITU-T Y.QKDNi_SDNC “Quantum Key Distribution Network
Interworking – Software Defined Networking Control” (TD304/WP3); 4) The updated
draft Recommendation ITU-T Y.QKDNf_fr “Framework of Quantum Key Distribution
Network Federation” (TD305/WP3); 5) The updated draft Technical Report ITU-T
TR-QN-UC “Use cases of quantum networks beyond QKDN” (TD307/WP3); 6) The
updated draft Supplement ITU-T Y.supp.QKDN-UC “Use cases of quantum key
distribution networks” (TD308/WP3); 7) The updated draft Recommendation ITU-T
Y.QKDN-AMC “Quantum key distribution networks - Requirements and architectural
model for autonomic management and control" (TD306/WP3); 8) The updated draft
Recommendation ITU-T Y.QKDN-TSNfr “Framework for integration of quantum key
distribution network and time sensitive network " (TD310/WP3); 9) The updated
draft Recommendation ITU-T Y.QKDN-rsrq “Requirements for quantum key
distribution network resilience” (TD309/WP3); 10) The updated draft Technical
Report on "Overview for integration of quantum key distribution network with
non-quantum cryptographies” in (TD311/WP3); 11) The consented draft
Recommendation ITU-T Y.3817 (ex Y.QKDN-qos-iw-req) “Quantum key distribution
networks interworking - Requirements of quality of service assurance"
TD463/WP1); 12) The consented draft Recommendation ITU-T Y.3816 (ex
Y.QKDN-qos-ml-fa) “Quantum key distribution networks: Functional architecture
enhancement of machine learning based quality of service assurance" (TD461/WP1).