Research on Secure Authentication and Access Control for Device Access Based on Distributed Architecture

The rapid proliferation of the Internet of Things (IoT) and the increasing heterogeneity of connected devices have exposed the limitations of traditional centralized authentication and access control systems. These conventional approaches struggle to meet the demands of high concurrency, cross-domain interoperability, and decentralized trust. To address these challenges, this paper proposes a distributed security authentication and access control framework that integrates blockchain and edge computing technologies. The proposed model introduces Decentralized Identifiers (DID) and zero-knowledge proofs (ZKP) to enhance identity authentication privacy and integrity. Additionally, it adopts a hybrid access control mechanism that combines Attribute-Based Access Control (ABAC) with Role-Based Access Control (RBAC), enabling fine-grained and dynamic policy enforcement. The system is structured in a three-tier architecture, where smart contracts deployed on a consortium blockchain ensure tamper-proof policy execution and auditability. Experimental evaluations show that the model significantly improves authentication latency, accuracy, and resilience against various attack scenarios, while maintaining policy flexibility and scalability. This work provides a practical and effective solution for secure and trustworthy device access management in complex IoT environments.