DBDAA: Dual blockchain and decentralized identifiers assisted anonymous authentication for building IoT

Abstract

The rapid advancements in the Internet of Things (IoT) and blockchain have made building IoT a critical element in modern intelligent building management. However, with the increasing adaptability of building IoT systems, concerns about data security and privacy have risen. Traditional solutions often rely on a single user identity, which poses security risks. Additionally, these solutions overlook the security of user permission information in access control systems. As a result, users with elevated permissions become prime targets for attacks. Existing key management mechanisms also have shortcomings, especially in key recovery processes. To address these issues, this paper proposes an identity authentication mechanism leveraging dual-blockchain and decentralized identifier (DID) technology. In the proposed mechanism, we develop a lightweight authentication scheme for devices. We also create a multi-DID model for users and further propose an anonymous authentication scheme, to safeguard data privacy, identity, and permission information, striking a balance between anonymity and oversight. Moreover, we design a key backup and recovery scheme to safeguard against key loss or damage, increasing system reliability. Experimental results demonstrate that our scheme enhances security while reducing computational and communication overhead.