Lightweight Pseudo Random Number Generator for Embedded Systems

A cryptography algorithm for data transfer encryption provides confidentiality, requires considerable computing power, and is not commonly implemented in embedded systems with limited computing power, such as Programmable Logic Controller (PLC).PLC is the core component for automation and control in industrial automation.For decades, PLC has prioritized speed over security; program execution in PLC must be as efficient as possible.The cryptography algorithm uses a seed, the initialization vector, to encrypt the data with the cryptography key to strengthen the encryption.Pseudo Random Number Generator (PRNG) can be used as the initialization vector.This paper proposes the XORasm PRNG algorithm, the lightweight XORshift-based algorithm with a modified seed from the system's clock.The applied methodology generates and visualizes PRNG, tests the randomness, and implements the PRNG on compact PLC.XORasm is evaluated statistically with runs-test in simulation by comparing the algorithm to one of the simulated compact PLC's PRNG implementations.The findings from this research are that p-values demonstrate that XORasm is statistically and significantly more random than the current implementation, and there is evidence that XORasm's generated data distribution is practically random at a 99.95% confidence level, suitable for implementation in embedded systems as a lightweight PRNG.