3r3176. 3r3-31. In past material we talked about the prospects for quantum networks and the complexities that face their developers. Today we will tell you about which projects are engaged in domestic and foreign researchers. If you are interested in this topic, we invite under the cat. 3r3144.  3r3176. 3r3144.  3r3176. / CC BY-SA 3r3164.
3r3144.  3r3176. 3r3144.  3r3176. 3r3114. Where and why do we need quantum networks
3r3144.  3r3176. Data exchange in quantum networks occurs with the help of polarized photons, called qubits. Such networks cannot be “listened to”, since qubits are very fragile and change their meaning when read. As a result, parties exchanging data over secure channels can immediately identify the MITM attack. In this case, the phenomenon of quantum entanglement allows you to learn about the change in the properties of quantum particles at a distance. This feature can be used to generate random numbers at two points simultaneously. 3r3144.  3r3176. 3r3144.  3r3176. For these reasons, quantum networks have found application in distribution systems and the generation of cryptographic keys. 3r3144.  3r3176. 3r3144.  3r3176. 3r3114. Foreign development
3r3144.  3r3176. The development of quantum cryptographic key distribution systems is being carried out by many European countries, as well as the USA, China and other countries. 3r3144.  3r3176. 3r3144.  3r3176.
The first working draft of the quantum network was developed 3r348. DARPA
(Office of the US Department of Defense) back in 2001. It was created by the same organizations that previously engaged in the implementation of ARPNET. Now the quantum network is deployed in Massachusetts, where it connects several scientific and military organizations. 3r376. 3r3144.  3r3176. Some time later, the first commercial solutions appeared in the field of quantum cryptography. In 200? 3-33353. debuted
Navajo system from MagiQ Technologies 3r3-3160. which is used by NASA. The system uses the quantum key distribution protocol
BB84 3r33160. . This protocol assumes that the communication nodes have two connections: fiber-optic (quantum), over which the exchange of cryptographic keys, and the classical Internet connection for data transfer. This approach is used today. 3r3144.  3r3176. 3r3144.  3r3176. At the very beginning of zero, European researchers also carried out work on quantum cryptography technologies. An example would be the project 3r3633. SECOQC 3-333160. , created to maintain the state security of the European Union. In 200? the EU invested € 11 million in the project, and in 2008 the network was launched in Vienna. 3r3144.  3r3176. 3r3144.  3r3176. At that time, the main problem faced by the researchers was the difficulty of transmitting entangled qubits over long distances. In particular, the length of the MagiQ quantum network was limited to 30 kilometers. 3r3144.  3r3176. 3r3144.  3r3176.
The impact of the external environment destroys quanta (the effect is called 3r3744. Decoherence 3r3-360.). This effect is also the reason for the complexity of the long retention of the "entangled" state of quantum particles. 3r376. 3r3144.  3r3176. Today, there are active developments that address this difficulty. In particular, employees of the Delft Institute in Holland 3-3379. working on repeaters that should help increase the scale of networks. To conduct tests, they build a ten-kilometer quantum network between the city of Delft and the Hague. Later - by 2020 - it should connect four European cities. 3r3144.  3r3176. 3r3144.  3r3176. Also, some countries are working on implementing r3r385. satellite 3r33160. quantum cryptographic key distribution systems. For example, last year, Chinese engineers made the first in their history, 3r-387. quantum teleportation when transmitting data from space 3-333160. . 3r3144.  3r3176. 3r3144.  3r3176. Photons were transmitted to the ground using lasers. To reduce the effect of decoherence on the transmitted quantum particles, the satellite was taken to a 500-kilometer orbit. Thus, particles of light overcome a significant part of the path in a vacuum. At the same time, the influence of the atmosphere was reduced by locating the receiving station at a height of four kilometers above sea level in Tibet. At the beginning of this year, the staff of the Beijing Academy of Sciences used a satellite to carry out 3-33393. newsgroups 3-333160. using quantum communication. 3r3144.  3r3176. 3r3144.  3r3176. Jeremy Atkinson
/ CC BY 3r3164.
3r3144.  3r3176. 3r3144.  3r3176. 3r3114. How are things in Russia
3r3144.  3r3176. Experiments with quantum networks and the distribution of quantum keys are conducted in Russia. It is believed that the first in our country quantum network (and, more precisely, the line) was laid by researchers from ITMO University between the two buildings of the university. 3r3144.  3r3176. 3r3144.  3r3176. A couple of years later, the same specialists, together with colleagues from the Kazan Quantum Center, launched the first in Russia 3–3–3122. 3r3-33160 multi-node quantum network. . In total there were four nodes, they were located at a distance of 40 km from each other. Now researchers are working on laying a network from Kazan to Naberezhnye Chelny and are negotiating with 3r3124. by financial institutions 3-333160. interested in the adaptation of technology for the implementation of encrypted communications. 3r3144.  3r3176. 3r3144.  3r3176. Another development example - in 201? physicists from the Russian Quantum Center (RCC) laid the first quantum network in the conditions of the city. Fiber optic cables stretched between two bank branches in Moscow, located 30 kilometers from each other. Now experts from the RCC are working on a 250-kilometer line of quantum communication. It will run between the RCC office, the Skolkovo technology park and the Sberbank data center. The network is divided into ten sections with a length of 80 kilometers. Some segments of the network plan to transmit data using IR lasers. 3r3144.  3r3176. 3r3144.  3r3176. It can be expected that projects now sponsored by financial, scientific, and government institutions will, over time, make it possible to organize larger quantum networks. 3r3144.  3r3176. 3r3144.  3r3176. 3r3138. 3r3144.  3r3176. 3r3141. What else do we write on the blog on the website VAS Experts: 3r3144.  3r3176. 3r3144.  3r3176. 3r3146.  3r3176. 3r3158. 3r3149. Botnet "spamming" through routers - what you need to know
3r3161.  3r3176. 3r3158. 3r3154. Implementing IPv6 - FAQ for ISPs
3r3161.  3r3176. 3r3158. Firewall or DPI - protection tools for different purposes 3r3161.  3r3176.
3r3164. 3r3172. 3r3176. 3r3176. 3r3176.
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