The first in Russia multi-nod quantum network launched in Kazan
The main advantage of quantum communications is their absolute protection from channel eavesdropping. Single photons that serve as information carriers in optical quantum communications are changed irreversibly after any attempt of signal interception allowing user to know about any unauthorized listeners. Quantum communication technologies serve as a basis for the future network security and will be integrated into Internet of Things concept that will radically change the everyday technological life. That is why quantum technology is being developed by many leading scientists all over the world. The most significant quantum networks are already built in USA (DARPA), Europe (SEQOQC), Japan (Toshiba) and China.
(с) Photo: ITMO University
Pilot segment of Kazan quantum network connecting two of the four existing nodes was tested in August 2016; now the communication between all four nodes is fully functional. It utilizes the new communication protocol that has been optimized for the city network. The network is realized in the active optical fiber lines of the “Tattelecom” provider. Two of the nodes were located in the commutation stations of “Tattelecom” on the different banks of Kazanka river and the other two in the KNIRTU-KAI buildings. The nodes were 10 km from one another while the optical cable length between the nodes reached 30-40 km during the testing stage.
During the network launch the control sequences and the demo files as well as the audio data in the quantum telephone regime has been transmitted. The basis for that is side-bands quantum communication technology that during testing showed qubit transmission speed over 100 kbit/s across some network regions.
This project creates the basis for the national quantum communications infrastructure development. The technology is to lay ground for the new generation of the distributed secure networks: previously the network providers only provided the data delivery but now they will be able to also provide secure data transmission services, forming the multi-user trusted network. That will be achieved with the help of the scaling of our solution and development of the new standards in the field of quantum communications, – explains the chief of laboratory of quantum informatics of international institute of photonics and optoinformatics ITMO University and the Laboratory of quantum cryptography of Kazan quantum center Arthur Gleym. – Further development of Kazan network lies in two directions: firstly the improvement of the channel characteristics (e.g. speed, range) and secondly integration with other services starting with data processing centers and systems responsible for uninterrupted operation of the city economy and up to mobile communications for example messengers.
Arthur Viktorovich Gleym(с) Photo: ITMO University
Our collaboration with the ITMO is based on shared scientific interests and is very fortunate – comments the head of Kazan quantum center KNIRTU-KAI Sergey Moiseev. – The original scheme of quantum key distribution was created in Saint-Petersburg and we are helping to develop it. The laboratory KNIRTU-KAI has been working on quantum memory for more than 15 years, but our developments needed to have a practical implementation and our colleagues from ITMO needed quantum memory for the long-distance quantum communications. For more than two years now we successfully cooperate. In future we plan to create a quantum repeater (the signal amplifier that stores the quantum state and then transmits it through the channel, it allows one to increase the possible communication distance) and certify the network. Every day we conduct technical trials, develop the network, improve routing and stabilize the equipment.
Previously in Russia only two-node quantum networks were launched in urban conditions. The first one was developed in ITMO University in 2014: the scientists connected the two buildings via optical fiber cable. In the June of 2016 Russian quantum center announced the launch of the next city communication line between the two Gazprom bank buildings and in the September of 2016 MSU announced the launch of quantum communication line connecting two towns in Moscow region. The Kazan project is first to connect the network of several clients – developers say that multi-node network requires principally new approaches and solutions than a point to point systems.
Kazan quantum network is created within the framework of National technological initiative in the direction of SafeNet, that is oriented to the development of new personal safety systems and quantum communications in Russia with the support of Quantum technologies consortium.