Key Encryption Through Quantum Optics

Morteza Ahmadian, Rafael J. Vicente, Juan P. Brito +7 more

Optical encryption using Quantum keys retrieved from real QKD and QRNG systems will be demonstrated. Retrieved keys are expanded to the required bitrate and then used to encrypt the input bit stream at line speed.

Mitsuru Matsui, Toyohiro Tsurumaru

Atsushi Taniguchi, Yasuhiro Mochida, Chikara Sakae +7 more

The advent of quantum computers has raised the risk of eavesdropping and made it essential to apply post-quantum security to most communication services. Encryption processing is not a single function as it includes key exchange functions (e.g., PQC and QKD) and encryption protocols (e.g., IPsec, MACsec, and L1 encryption), and it is necessary to combine these functions to suit the requirements of each service. However, the encryption protocols of existing optical & packet transport equipment are vertically integrated and cannot be altered easily. In this paper, we propose a disaggregation architecture of post-quantum security for optical and packet transport equipment. By separating key management functions from their implementation, the architecture enables more secure encrypted communication by using more secure key exchange methods and implemented encryption protocols. In addition, we also propose a key splitting method that eliminates the impact on communication in the event of a failure due to the functional separation provided by the method; it supports various encryption ciphers. By using this method, key update can be continued even after a communication break interrupts key exchange. We show that 96 Gbps traffic can be encrypted without error.

Niccolò Somaschi, Shane Mansfield

Luis Antonio Guisso Lopes luis.guisso

Kexin Wang, Xinke Tang, A. Wonfor +5 more

Data security plays an increasingly important role in modern telecommunications. The advent of quantum computational processors presents a significant threat to today's widely employed public key encryption algorithms, necessitating the adoption of new approaches to data encryption. Whilst quantum key distribution guarantees unconditional security for cryptographic key exchange in optical communication networks, the data rate is slow (Mbit/s), especially when compared to conventional optical communication. Here we present a highly secure encryption approach in which the encryption key, generated by quantum key distribution at a rate of up to 2.9 Mbit/s, was used to seed physical layer encryption performed using time domain spectral phase encoding (TDSPE). This allowed us to demonstrate encrypted 40 Gbit/s quadrature phase shift keyed data communications over 52.3 km of installed optical fiber, which cannot be eavesdropped using brute force computational attacks. Any attempt to eavesdrop the encrypted signal in the physical layer is highly time-sensitive – the phase states must be measured and decrypted prior to optical signal attenuation, which means that the attack procedure typically needs to be completed within a few milliseconds. This work represents the first example of quantum-enhanced physical layer encryption at realistic optical data rates that is fully secure from brute force computational attacks and the first demonstration of TDSPE using continuous-wave laser source and quadrature phase shift key modulation.