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experiment by the SECOQC was inaugurated in the pres-ence of researchers and press in Vienna. e average transmission distance was 30 km, and the speed of key generation was 1 kbps. e performance was sucient to encrypt voice data. In Japan, in October 2010, NICT suc-ceeded in encryption of video data transmission by QKD by establishing the most advanced quantum cryptography network “Tokyo QKD Network”. Toshiba Research Europe Ltd., ID Quantique, Austrian Institute of Technology and the University of Vienna as well as NICT, NEC, Mitsubishi Electric Corporation and NTT participated in the experi-ment. e transmission distance extended to 50 km, almost twice that of the SECOQC, and the speed of encryption improved almost 100 times aer only two years since the experiment of the SECOQC. Also, we have developed an advanced application interface for interconnection of QKD devices with dierent specication of each institute. We stimulated various know-how by operating the network.In the eld of quantum metrology, a technology to measure frequency with high accuracy was developed by improving the assurance of frequency standards by cooling two kinds of ions in a cavity together.3The Third Medium- to Long-Term Plan (FY2011-2015)During the ird Medium-to Long-Term Plan, we took on the challenge of developing a quantum receiver which is a basic component in quantum communication, using the world’s top-level photon resolving detector. is is a receiver that performs quantum computing for single opti-cal signal pulse and realizes the minimum bit error rate. NICT succeeded in verifying the principle of a quantum receiver for the rst time in the world in 2011. Also, in 2013, we veried our original idea of “quantum amplica-tion transmission” that transmits an input optical signal a far distance by noiseless amplication, that was an applied technology of the cat’s state generation. However, the performance of these technologies is still limited to certain conditions such as in a laboratory. e practical application of super Shannon limit communication is still a very dif-cult technology so that a drastic and new technology needs to be developed. Actually, it is limited to realizing it using only optical elements. It may be necessary to adopt a superconductive device to realize stronger non-linear interaction. In the latter of the ird Medium-to Long-Term Plan, a new study on strong coupling of magnetic quantum bits and microwave quanta on a superconductive device was started.In the eld of quantum cryptography, we took on the challenge of developing a new security application that works on the Tokyo QKD Network. At rst, the technol-ogy that supplies a cryptographic key generated by quantum cryptography to IP routers of two hubs to completely conceal each IP packet and to authenticate to prevent fal-sication was developed. is technology enables freely constructing a private network that is completely concealed between hubs for important communication through an open system on the internet. Also, a technology to com-pletely conceal wireless communication by supplying a cryptographic key to smartphones or drones was developed.e technology of quantum cryptography was trans-ferred to the related divisions of NEC and Toshiba. In 2015, test operation started within areas of users’ condition in Tokyo and Sendai city. Experiments to conrm reliability have been performed continuously.In the eld of quantum measurement standards, quan-tum theory spectroscopy was developed that controls or transcribes information between ions of time transition and ions of co-cooling and readout.4The Fourth Medium- to Long-Term Plan (FY2016-2020)e research and development of quantum ICT in NICT is the history of appearance of and development in this eld. Since the establishment of the laboratory in 2001, we have boldly moved to verify the new principles of quantum ICT and to research and develop practical use of it, which are two main axes of basic and applied research. Basic research has been heading to the next research phase in which we investigate new phenomena of integrated systems of several physical systems such as light, ions and superconductivity and to exploit applications in ICT. In the future, it will be possible to overcome the limit of conven-tional transmission capacity or measurement standards by introducing such integrated systems to nodes of a network and forming a “quantum node.” However, there still remain many problems for practical use so that long-term basic research is needed. Applied research is spreading wide and merger of quantum cryptography and present cryptography and application of elemental technology to moving bodies is progressing, exploiting new faces in the elds of cryp-tography and network technology. Especially, from the research conducted in order to overcome the limit of dis-tance or speed of quantum cryptography came a new region 31 Intoroduction