A Study on an ITS Security Framework Using an Optimized RNS Montgomery-Based Security Algorithm

Intelligent Transport Systems (ITS) are rapidly transforming modern transportation through real-time data exchange between vehicles and infrastructure. As these systems increasingly rely on seamless communication, ensuring both security and low latency is paramount. However, traditional encryption algorithms, such as RSA and ECC, often impose computational burdens that are incompatible with the stringent time and energy constraints of ITS environments. To address this challenge, we propose a novel security framework that integrates the Residue Number System (RNS) with Montgomery modular multiplication. This combination enables e cient modular arithmetic through parallel processing, reducing the overall computational complexity. The framework was implemented and evaluated within a simulated Vehicle-toEverything (V2X) environment using OMNeT++ and SUMO. The results demonstrate that the RNS-Montgomery approach reduces encryption time by approximately 34% and energy consumption by nearly 29% compared to traditional methods, while maintaining equivalent cryptographic strength. The proposed framework o ers a viable and scalable solution for secure ITS communications. Its efficiency and resistance to side channel attacks position it as a promising direction for future deployment in latency-sensitive and resource-constrained vehicular networks.