This item is available under a Creative Commons License for non-commercial use only
The work reported in this thesis commenced with a review of methods for creating random binary sequences for encoding data locally by the client before storing in the Cloud. The first method reviewed investigated evolutionary computing software which generated noise-producing functions from natural noise, a highly-speculative novel idea since noise is stochastic. Nevertheless, a function was created which generated noise to seed chaos oscillators which produced random binary sequences, and this research led to a circuit-based one-time pad (OTP) key chaos encoder for encrypting data. Circuit-based chaos systems, initialised with electronic noise, were simulated in a linear circuit simulator called PSpice. Many simulation problems were encountered because of the nonlinear nature of chaos but were solved by creating new simulation parts, tools and simulation paradigms. To identify chaos sources which would produce OTPs with maximum entropy, simulation data from a range of chaos sources was exported and analysed using Lyapunov analysis. This led to a two-chaos electronic encoding system which could generate unlimited, infinitely-long period, unique random one-time pad encryption keys for plaintext data length matching. The keys were studied for maximum entropy and passed a suite of stringent internationally-accepted statistical tests for randomness. A prototype containing two delay chaos sources initialised by electronic noise, was produced on a double-sided printed circuit and produced more than 200 Mbits of OTPs. According to Vladimir Kotelnikov in 1941 and Claude Shannon in 1945, OTP sequences are theoretically-perfect and unbreakable, provided specific rules are adhered to. Two other techniques for generating random binary sequences were researched; a new circuit element, memristance was incorporated in a Chua chaos oscillator, and a fractional-order Lorenz chaos system with order less than three. Quantum computing will present many problems to existing cryptographic system security when realised in hardware in the near future, and only the unconditionally-secure OTP key system encoding system will resist cryptanalysis by QC.
Tobin, P. (2018) On the Application of PSpice for Localised Cloud Security. Doctoral thesis, DIT, 2018.