DWDM is a technology that makes it possible to increase the capacity of optic channels by a hundred times.

TTK has upgraded the network on the basis of dense wavelength division multiplexing (DWDM) technology, having created the largest fully geographically redundant DWDM-network in Russia with a total length of more than 30,000 km. Upgraded network capacity was increased by 20 times and now comprises 560 Gbps in the main backbones. Geographical distribution of routes provides complete signal redundancy throughout its length. In case of signal loss, the time for switching to a backup route is 38 milliseconds. This complies with the recommendations of the International Telecommunication Union.

One of the significant benefits of TTK DWDM network is its total homogeneity. Delivery of equipment, installation, and commissioning were carried out by one contractor - Huawei Company (Huawei Technologies Co., Ltd.). This ensures optimum consistency and balance of all network elements. The network development project provides the possibility of a subsequent increase in capacity up to 1600 Gbps without transmission interruptions.

The upgrade of the DBN enabled the release of additional resources for process needs of the TTK shareholder (OJSC RZhD), an increase in the scope of modern information technology implementation in the railway industry, and provision of a higher security level for train traffic, and will help to increase the transit capacity of Russian railways. Moreover, the DWDM network enabled TTK to expand the range and quality of its services in the Russian telecommunications market.