HACEC: Efficient and Auditable Anonymous Access Control for Edge Computing Services

In recent years, edge computing has undergone significant growth, but ensuring anonymity, efficiency, and auditability in service utilization remains challenging. This paper proposes HACEC, an efficient and auditable anonymous access control scheme for edge computing. HACEC utilizes a dual-token mechanism to achieve anonymity and efficient service utilization. It allows users to access services using temporary identities, without exposing their real identities. We integrate the Trusted Execution Environment (TEE) and threshold cryptography into this mechanism to prevent several attacks. This mechanism not only protects users' identity privacy but also avoids reliance on an always-online cloud, thereby addressing the issue of a single point of failure. Additionally, HACEC proposes an auditable Multi-Authority Attribute-Based Encryption (MABE) scheme and a hierarchical audit mechanism to achieve efficiency and security in audit. The system separates the audit process into data audit and identity tracing. Data audit would not expose users' identities and is performed efficiently through the MABE scheme. Once malicious behaviors are detected, identity tracing can be performed in a threshold manner to retrieve the identities. As a result, HACEC achieves a trade-off between efficiency, security, and auditability. We provide a comprehensive security analysis and performance evaluation to demonstrate the security and efficiency of HACEC.