Biblio

Cryptography is one of the important aspect of data and information security. The security strength of cryptographic algorithms rely on the secrecy and randomness of keys. In this study, bitwise operations, Fisher-Yates shuffling algorithm, and cipher text mapping are integrated in the proposed TRNG key generator for One-Time Pad cryptography. Frequency monobit, frequency within a block, and runs tests are performed to evaluate the key randomness. The proposed method is also evaluated in terms of avalanche effect and brute force attack. Tests results indicate that the proposed method generates more random keys and has a higher level of security compared with the usual OTP using PRNG and TRNGs that do not undergo a refining phase.

In cryptography, one-time pad (OTP) is claimed to be the perfect secrecy algorithm in several works if all of its features are applied correctly. Its secrecy depends mostly on random keys, which must be truly random and unpredictable. Random number generators are used in key generation. In Psuedo Random Number Generator (PRNG), the possibility of producing numbers that are predictable and repeated exists. In this study, a proposed method using True Random Number Generator (TRNG) and Fisher-Yates shuffling algorithm are implemented to generate random keys for OTP. Frequency (monobit) test, frequency test within a block, and runs tests are performed and showed that the proposed method produces more random keys. Sufficient confusion and diffusion properties are obtained using Pearson correlation analysis.

Quantum Key Distribution (QKD) is a technique for sharing encryption keys between two adjacent nodes. It provides unconditional secure communication based on the laws of physics. From the viewpoint of network research, QKD is considered to be a component for providing secure communication in network systems. A QKD network enables each node to exchange encryption keys with arbitrary nodes. However previous research did not focus on the processing speed of the key management method essential for a QKD network. This paper focuses on the key management method assuming a high-speed QKD system for which we clarify the design, propose a high-speed method, and evaluate the throughput. The proposed method consists of four modules: (1) local key manager handling the keys generated by QKD, (2) one-time pad tunnel manager establishing the transparent encryption link, (3) global key manager generating the keys for application communication, and (4) web API providing keys to the application. The proposed method was implemented in software and evaluated by emulating QKD key generation and application key consumption. The evaluation result reveals that it is capable of handling the encryption keys at a speed of 414 Mb/s, 185 Mb/s, 85 Mb/s and 971 Mb/s, for local key manager, one-time pad tunnel manager, global key manager and web API, respectively. These are sufficient for integration with a high-speed QKD system. Furthermore, the method allows the high-speed QKD system consisting of two nodes to expand corresponding to the size of the QKD network without losing the speed advantage.