Improved Quantum Key Distribution Networks Based on Blom-Scheme

Abstract

With the mature implement of point-to-point quantum key distribution (QKD) system, QKD networks become the focal points of the research. In general, QKD network is a simple extension of point-to-point QKD systems. An N-user QKD network is constructed with \(O(N^2)\) point-to-point QKD systems, which consumes a great deal of resources. We first propose an improved QKD network based on Blom-scheme, which reduces the number of point-to-point QKD systems from \(O(N^2)\) to O(N) and maintains unconditional secure. Then we develop it to a multiple-centre network. Moreover, as denial-of-service is a normal and effective attack on quantum communication system, we creatively construct a network architecture based on block design against the attack. Our network architecture can reduce the cost of the quantum channels greatly and improve the survivability compared to the existing QKD networks.