Comparison of 4 Multi-User Passive Network Topologies for 3 Different Quantum Key Distribution

The purpose of this paper is to compare the performance of four passive optical network topologies in implementing multi-user quantum key distribution, using 3 protocols proposed by quantum cryptography (B92, EPR, and SSP). The considered networks are the passive-star network, the optical-ring network based on the Signac interferometer, the wavelength-routed network, and the wavelength-addressed bus network. The quantum bit-error rate and sifted key rate for each of these topologies are analysed to determine their suitability for providing quantum key distribution-service to networks of various sizes. The efficiency of the three considered protocols is also determined.