Ensuring the security of information exchange in optical communication systems has become one of the primary challenges in telecommunication networks. In current communication systems the security measures are mainly implemented by digital data encryption methods (such as AES). The strength of the security is determined by the computational difficulty of breaking the encryption algorithms, described as computational security. On the other hand, time domain spectral phase encoding (TDSPE) implements network security in the optical physical layer by rapid (bit-by-bit) encoding of the high-speed optical signal into a noise-like optical signal, which is referred to as physical level security.
In Phase 1 of the Quantum Communication hub, the academic teams (Heriot Watt and Cambridge) carried out a feasibility study of a hybrid system using quantum key distribution (QKD) and TDSPE to enable both computational and physical level security in an optical communication system. In this project, the academic groups will team up with industrial partner (BT) to integrate QKD for secure key distribution with TDSPE for physical layer high speed signal scrambling in one system and quantum level security in the key exchange and physical level security in data transmission. By using such physical layer encryption, we are able to provide ultra-high security whilst maintaining Gbps data transmission rates. We aim to develop a fully integrated system that acts as a “plug-and-play” security module, and apply this to higher data-rate optical communication and demonstrate in a series of field trials. Intellectual properties on the technology will be generated from this project.