The longest transmission link of the Quantum Key Distribution technology in Europe has been launched as part of the NLPQT project. The infrastructure of the intercity link between Poznan and Warsaw is a direct extension of the earlier installed infrastructure of the NLPQT project – QKD links in Poznan – and the next stage of research and implementation of QKD systems. The QKD transmission system on the Poznan – Warsaw route uses dedicated PIONIER network fibers with the total length of all optical paths equal to 380 km. The system has been designed and built in the configuration of the so-called “trusted nodes” and has five intermediate transmission nodes, allowing for individual use of the services of the QKD system. This approach enables flexible system configuration and launching independent QKD services between selected intermediate nodes. In the case of the key transmission via intermediate nodes, the key handover is performed at the hardware level so as to ensure link and service integrity between the end nodes. The intermediate nodes serving as “trusted nodes” in the link topology are PIONIER network telecommunications objects with the full supervision and management conducted by the PSNC supervision center. The QKD Poznań – Warsaw link is based on the latest generation of IDQuantique devices – CerberisXG. The QKD transmission system is monitored and managed by a team of PIONIER network administrators.

The long-distance QKD Poznań – Warsaw link opens up new opportunities for the NLPQT consortium to carry out research and projects related to QKD technology networks and quantum communication. The infrastructure also enables conducting new research related to the integration of QKD links with the current network infrastructure and the implementation of a number of usage scenarios, applications and services based on QKD technology.