Design of quantum cryptography systems for passive optical networks

Quantum cryptography has been shown to be an effective technique for the secure distribution of cryptographic keys on point-to-point communication links. The authors describe adaptations of the existing quantum cryptography protocols and equipment configurations that allow secure key distribution to be performed on a variety of multiuser passive optical network (PON) architectures. These adaptations enable the network controller on the PON to distribute individual secret keys to each user on the network, and hence to securely encrypt and authenticate subsequent data transmissions broadcast on the network.