Optimum design for BB84 quantum key distribution in tree-type passive optical networks

TL;DR

This paper investigates the optimal design of tree-type passive optical networks for BB84 quantum key distribution, balancing key rate and fiber length, and proposes a two-stage splitting architecture with optimal ratios under security considerations.

Contribution

It introduces a two-stage splitting architecture and derives the optimal splitting ratios for secure quantum key distribution in PONs.

Findings

Optimal splitting ratios depend on physical parameters and security attacks.

Tradeoff identified between key rate and fiber length in PONs.

Proposed architecture enhances secure quantum communication efficiency.

Abstract

We show that there is a tradeoff between the useful key distribution bit rate and the total length of deployed fiber in tree-type passive optical networks for BB84 quantum key distribution applications. A two stage splitting architecture where one splitting is carried in the central office and a second in the outside plant and figure of merit to account for the tradeoff are proposed. We find that there is an optimum solution for the splitting ratios of both stages in the case of Photon Number Splitting (PNS) attacks and Decoy State transmission. We then analyze the effects of the different relevant physical parameters of the PON on the optimum solution.