Nec Corporation

Eduardo F Mateo Rodriguez

Ryuji Aida

Philip N Ji

Yoshihisa Inada

A hybrid Quantum Key Distribution (QKD) protocol and method for secure transmission in optical communications systems and in particular long distance optical communications systems such as those in undersea environments. Our inventive method advantageously exploits fundamental security features of quantum-base encryption with the added intrinsic security of encapsulated and sealed equipment of undersea optical networks. Our method employs an intermediate node that generates an optical signal, and a pair of quantum state generators that respectively generate quantum states of the optical signal and transmit the generated quantum states to secure nodes, respectively. The secure nodes then communicate securely using a quantum key distribution (QKD) protocol.

Hybrid quantum cryptography protocol for optical communications

An optical transmission apparatus outputs a main signal. An optical transmission apparatus superimposes a monitoring signal on an optical signal and outputs it. A submarine branching apparatus includes a return unit configured to return the monitoring signal received from the optical transmission apparatus and is configured to switch an output destination of the main signal received from the optical transmission apparatus to an optical transmission apparatus or the optical transmission apparatus. The optical transmission apparatus is configured to detect the monitoring signal returned from the return unit and notifies the optical transmission apparatus of a result of the detection. The optical transmission apparatus instructs the submarine branching apparatus to switch the output destination of the main signal in accordance with the notification.

Submarine optical communication system and submarine branching apparatus

A method for data transport that includes providing a branch terminal between a first and second trunk terminal, wherein a branching unit is present at an intersect between the first and second trunk terminal and the branch terminal. The branching unit includes a reconfigurable add/drop multiplexers (ROADM) at least one attenuator. A signal is sent from a second terminal of the first and second trunk terminal to the branding unit. The signal may include a branch traffic component trunk traffic component. The branching unit includes at least one attenuator for attenuating the trunk traffic component so that the trunk traffic component of the signal cannot be detected at the branch terminal.

Growing community of inventors

Tokyo, Japan

Eduardo F Mateo Rodriguez