Technology Applied in QKD-TELCO

● Polarisation-entangled QKD SystemImage
Key element in QKD-TELCO is a source of entangled photon pairs, which will be used in a portable QKD-system that distributed secret keys among end users. In the optimal case a “universal” narrow-band Sagnac source that is compatible for all network segments in the modern IT infrastructure provides a high delivered key rate and, in addition, the possibility to tune the optical emission frequency for the purpose of additional wavelength stacking. Reduced cost is obtained by reducing the number of required single-photon detectors to just a single one, while still retaining a high secure key rate.
The QKD system will be practically integrated into the IT infrastructure in combination with hardware encryption modules. Interoperability between QKD hardware and classic security modules will be facilitated through the developed QKD stack.

● Physical Robustness and Prevention of Attacks
QKD-TELCO introduces robust QKD technology laid out for co-existence of classical signals that introduce wideband noise, e.g. through Raman scattering at the optical distribution network. Support will be provided by an accurate analytical model that takes into physical channel parameters, subsystem imperfection (e.g. single-photon detector impairments) and the QKD stack used for secret key extraction. Optimal filtering and multiplexing schemes based on these predictions are then applied to guarantee high key rates in noisy environments.
Moreover, countermeasures and strategies against “side channel attacks” and “quantum hacking” are implemented in QKD-TELCO. Immunity against these attacks is obtained by redesign of typically vulnerable elements of the overall QKD system, such as single-photon detectors.

● Performance monitoring for QKD-upgraded telecom networks
In addition to classic means of link monitoring QKD-TELCO adopts performance monitoring for its quantum channels through a wideband single-photon spectrometer with utmost sensitivity to noise photons. Adaptation of the wavelength plan in view of different network conditions and load ensures that the highest possible key rate is distributed to the end users.