A Fine-Grained Access Control Mechanism Based on Search Trees

The security of cloud-based databases is a crucial topic in current research. The primary solutions are focused on access control and data encryption. A central challenge these solutions face is navigating the balance between system security and operational efficiency. However, individualized data privacy requires fine-grained data protection at columns/rows or individual elements. In existing fine-grained resource or policy protection methods, resource access predominantly uses a traversal method, leading to a linear growth in time overhead. In response to these issues, this paper presents a fine-grained access control mechanism based on search trees. This mechanism provides element-level resource protection and accelerates policy search using an index tree, thereby reducing the time overhead of the fine-grained access control system. Experimental results demonstrate that this mechanism achieves element-level resource protection while maintaining low-performance overhead.