| 1 Recommendation for a Cryptographic Communications Network Framework
| Preliminary approval as international standard ITU-T Y.3800
SK Telecom Develops Quantum Cryptography Switching Technology

Quantum cryptography technology is a next-generation communication security technology that makes wiretapping and eavesdropping impossible.

Quantum cryptography technology is also called 'quantum key distribution technology', which safely distributes an encryption key, or a one-time random number table, between a sender and a receiver in real time based on the laws of quantum mechanics, such as the impossibility of quantum cloning.

Recently, the three major domestic mobile carriers have shown a clear trend toward developing quantum cryptography technology.

The three major mobile carriers recently ushered in the 5G era. While 5G boasts ultra-high speeds, ultra-low latency, and hyper-connectivity, its structure, which processes data even at the base station level, presents security vulnerabilities. This problem will become more serious with 6G, which will be released within 10 years.

Accordingly, the three mobile carriers appear to have chosen quantum cryptography as a security measure.


Domestic quantum cryptography technology receives preliminary approval as an ITU international standard.
KT and LG Uplus announced on the 1st that one recommendation for a cryptographic communication network framework was tentatively approved as an international standard (ITU-T Y.3800) at the International Telecommunication Union Telecommunication Standardization Sector Study Group (ITU-T SG13) international conference held in Geneva, Switzerland from June 17th to 28th.

This is the world's first standard adopted in the field of quantum cryptography communication within the ITU, and it is expected to be circulated among member countries and ultimately adopted if there are no objections.

This standardization is the result of seven domestic organizations and approximately 20 member companies around the world actively participating in standardization activities following the proposal and development by KT, LG U+, the Korea Institute of Science and Technology (KIST), and the Electronics and Telecommunications Research Institute (ETRI).

The approved standard defines the layer model and functional components required to configure a quantum cryptography communication network, and is significant in that it sets a new standardization standard by considering all areas from the perspectives of operators and manufacturers in the still controversial field of quantum cryptography communication.

Through this standard development, we have confirmed the patent aspect and resolved the technological monopoly, thereby shifting the leadership in international standardization in the field of quantum cryptography from existing foreign equipment manufacturers to telecommunication service providers, thereby leading the market.
/> Accordingly, it is expected that domestic companies will be able to secure a technological advantage in competition with large overseas companies in the quantum cryptography communication market and also expand into overseas markets.

Future ITU standardizations will be based on this framework, with the ITU-T Y.QKDN_Arch (detailed structure), ITU-T Y.QKDN_KM (key management), ITU-T Y.QKDN_CM (network management/control), and ITU-T Y.QKDN_SDNC (SDN controller) tasks scheduled to be standardized by September 2021.

At this ITU-T SG13 meeting, a new standardization project (Y.QKDN_CM: Quantum Cryptography Communication Control and Management) jointly proposed by KT and ETRI was also approved.

Based on the quantum cryptography communication network configuration technology stipulated in Y.3800, a new standard is expected to be developed to ensure the stable supply and high-quality operation and management of quantum cryptography services.

KAIST Professor Choi Jun-gyun said, “This is a significant achievement in that Korea has taken the lead in standardizing quantum cryptography technology, so that the AI-based intelligent cyber society that will emerge in the future can move toward a safe and trustworthy cyber ecosystem.”

KT Convergence Technology Research Center Vice President Jeon Hong-beom said, “KT has been pushing for the reflection of domestic technology in international standards to achieve the world’s first ITU standard approval for this quantum cryptography communication network technology,” adding, “It will be one of the future technologies.”“We will continue to work to develop quantum cryptography network technology, a new security platform,” he said.

LG Uplus NW Development Group Leader Park Song-cheol said, “LG Uplus has presented a new network model for quantum information communication in collaboration with businesses, industries, and research institutes. We will continue to strive to secure a win-win ecosystem to provide better services to our customers.”


SK Telecom Completes Development of Quantum Cryptography Switching Technology
On June 28, SK Telecom, along with ID Quantique (IDQ), a quantum information and communication specialist, and the Institute for Information and Communications Technology Planning and Evaluation (IITP), completed the national quantum cryptography test network project, “Development of key elements for reliability verification technology and advanced distribution of quantum cryptography networks.”

Through this project, SK Telecom developed a quantum cryptography key "switching" technology. Switching technology transfers quantum cryptography keys in the opposite direction when a network failure occurs.

We have also successfully applied the quantum cryptography key 'routing' function to equipment connecting multiple networks. Routing is a function that sets one of several paths, and you can freely set the path through which the quantum cryptography key is transmitted.
SK Telecom completed the application of quantum cryptography technology to its 362km-long, figure-of-eight test network this year. This technological development suggests that quantum cryptography can be applied to networks of all structures.

In addition, SK Telecom passed the technical contents to be reflected in the standard, such as ▲ matters to consider in terms of encryption key request and transmission reliability when connecting quantum cryptography networks and existing communication networks ▲ contents related to automatic operation when quantum cryptography equipment is restarted, in the 'Quantum Cryptography Communication Network Framework', which is undergoing international standardization work at ITU-T SG13.

Park Jin-hyo, head of SK Telecom's ICT Technology Center, said, "SK Telecom is working with global operators and vendors such as IDQ, Telefónica, BT, and Toshiba to create a global quantum cryptography ecosystem," and added, "We will continue to participate in the global standardization of quantum cryptography centered around the ITU-T to increase the completeness of the standards."


What is the future of quantum cryptography technology in Korea?
The importance of communication network security is growing day by day in terms of protecting national, corporate, and financial confidential information and protecting individual privacy.

Quantum information processing and quantum information communication technologies, which began to be studied in earnest in the mid-1980s, can perform various tasks previously thought impossible with existing technologies by directly expressing and processing information in quantum states.

Among quantum information and communication technologies, quantum cryptography is the most fundamental and technologically mature. Currently, active research is being conducted globally, primarily in major countries like the US, Europe, and Japan. Now, we can look forward to the activities of Korean institutions and companies as well.