A Blockchain-Based Secure Architecture for Cyber-Physical Systems in Smart City Infrastructure

Abstract

The rapid evolution of smart cities has led to widespread deployment of Cyber-Physical Systems (CPS) for real-time monitoring and control of urban infrastructure, encompassing domains such as intelligent transportation, energy distribution, and public safety. However, the integration of heterogeneous devices and distributed control units presents significant challenges related to data security, system interoperability, and trust management. Traditional centralized architectures are increasingly vulnerable to cyber-attacks, data manipulation, and single points of failure, necessitating the development of secure and scalable alternatives.This study proposes a blockchain-based architecture designed to enhance the security, transparency, and resilience of CPS in smart city environments. The primary objective is to leverage the decentralized nature of Distributed Ledger Technologies (DLTs) to provide immutable data storage, secure device authentication, and verifiable access control through smart contracts. The proposed architecture is structured in a multi-layered model, comprising the IoT perception layer, an edge computing layer for localized processing and consensus participation, and a blockchain layer built on a permissioned ledger (Hyperledger Fabric) optimized for low-latency transactions.To validate the proposed framework, simulation-based case studies were conducted across three critical urban scenarios: intelligent traffic management, smart grid monitoring, and video surveillance. The implementation includes the deployment of edge nodes with integrated consensus logic, smart contracts for access policy enforcement, and secure data exchange protocols using cryptographic hashing and digital signatures.Key performance metrics such as latency, throughput, scalability, and resilience to cyber threats were analyzed. The experimental results show that the blockchain-enabled CPS architecture reduces average latency by 28%, enhances data integrity verification by 35%, and achieves over 95% accuracy in device authentication, compared to traditional centralized approaches. Additionally, the system demonstrated strong resistance to spoofing, tampering, and unauthorized access attacks under dynamic load conditions.In conclusion, this study establishes that blockchain-integrated CPS frameworks can significantly improve the security and operational reliability of smart city systems. Future work will explore the incorporation of federated learning for intelligent decision-making, cross-chain interoperability, and energy-efficient consensus mechanisms suitable for resource-constrained edge environments.