Routing and wavelength assignment in hybrid networks with classical and quantum signals

TL;DR

This paper introduces heuristics for routing and wavelength assignment in hybrid classical-quantum networks, aiming to optimize quantum key distribution performance by minimizing interference from classical signals.

Contribution

It presents a novel heuristic method tailored for hybrid networks that enhances quantum channel quality by reducing classical-quantum interference, outperforming traditional RWA approaches.

Findings

Heuristics reduce shared paths between classical and quantum channels.

Improved signal-to-noise ratio in quantum channels.

Enhanced quantum key rate compared to classical RWA methods.

Abstract

Quantum Key Distribution has become a mature quantum technology that has outgrown dedicated links and is ready to be incorporated into the classical infrastructure. In this scenario with multiple potential nodes, it is crucial having efficient ways to allocate the network resources between all the potential users. We propose a simple method for routing and wavelength assignment in wavelength multiplexed networks in which classical and quantum channels coexist. The proposed heuristics take into account the specific requirements of quantum key distribution and focus on keeping at bay the contamination of the quantum channels by photons coming from the classical signals by non-linear processes, among others. These heuristics reduce the shared path between classical and quantum channels and improve the signal-to-noise ratio in the quantum channels, improving their quantum key rate. We compare the results to the usual classical RWA approach.