Quantum cryptographic key distribution in multiple-access networks

The purpose of quantum key-distribution is for two or more correspondents, who share no secret information initially, to agree on random keys, which remain secret against attacks from more powerful analytic or computational tools. Quantum cryptography protocols can be designed to offer guaranteed security services in optical communication networks. The paper briefly outlines a general procedure for modeling and simulation of quantum key distribution protocols in multiple-access networks. Each communication network model is assumed to be composed of communication nodes (stations) that are connected by links. There are three basic communication node models, which are quantum transmission (QT), quantum reception (QR), and quantum transmission reception (QTR) nodes. In the models, fiber optic channels (links) are assumed to be used for connecting communication nodes