Scientists from the Russian Quantum Center (RQC) managed to launch the first multi-node quantum network in Russia for data transmission. In the development of domestic specialists, two methods of information encryption are used simultaneously, which makes this method of data transmission extremely secure.
The first quantum networks began to appear in our country three years ago, and a working communication line was launched at ITMO University in 2014. This line connected two buildings of the university with a quantum channel. In June last year, the launch of the first "city" communication line between the two branches of the bank was announced, and in September 2016 the press service of Moscow State University announced the connection of two points in the cities of the Moscow region. In May this year, the first in Russia session of quantum "telephone" communication was held in Kazan. The current development of RCC employees is a quantum network consisting of three nodes and two quantum channels connected to each other. A quantum secure link itself can only be established directly between two points, and if the network has a complex structure,then the quantum network segments must be connected to each other by nodes with repeaters, which use "normal" data processing methods. These "normal" nodes create security holes that practically negate all the benefits of using quantum lines for secure data transmission. According to the employee of the RCC Alexey Fedorov,
“Methods of quantum data protection are well developed in laboratory conditions, but when they are transferred to the existing telecommunication and cryptographic infrastructure, many problems arise, in particular, when using real urban communication lines. We managed to successfully solve one of them - the use of two different methods of encoding information in the same network”.
To improve protection on a branched communication line, specialists used information encryption using quantum keys on "normal" sections of communication lines. On the basis of fiber-optic networks, 2 channels were created: 30 and 15 kilometers long, respectively. In the first of the sections, the data were encoded using the polarization of photons, in the second, in their phase. In the course of the experiment, the rate of generation of quantum keys in the first section was 0.1 kilobits per second, and the rate of generation of a secret key suitable for encryption was 0.02 kilobits per second.
“This key generation rate is sufficient to update keys in existing encryption devices. In future experiments, the generation rate can be increased. The use of two coding methods within one network makes it possible to use existing software solutions and platforms for data processing and encryption. This saves banks and other users of quantum networks from the need to develop new products, but simply makes it possible to embed quantum channels into the existing telecommunications infrastructure."
Based on materials from RIA Novosti
VLADIMIR KUZNETSOV