High-Speed Quantum Encryption over a Classical Network

This SBIR Phase-II project further develops an exciting new invention in the field of quantum cryptography that will secure the physical layer of today's ubiquitous fiber-optic data networks. Unlike the techniques that are based on single-photon states which are confined to low bit rates and short distances, our approach is based on coherent states emitted by ordinary lasers that permits scaling to data-rates used in today's networks as well as deployment over realistic distances (>500 km). Our Phase-I project showed via simulations and experiments that operation of our data encryption technology in today’s WDM networks is possible. We demonstrated data rates of 622Mb/s over 500 km in a live WDM network. We also created a block-level design for a system that would operate at 2.5Gb/s. In this Phase-II, we propose to build and demonstrate such a 2.5Gb/s optical encryption system. In addition to the rate upgrade, several other improvements will be made to the system to increase its security level, performance, and practicality. For instance, we will use the Advanced Encryption Standard (AES) to generate the internal stream cipher, exploit FEC coding and balanced detection, as well as include a method for automatically synchronizing the encryptor with the decryptor.