A Secure Cloud-Edge Collaborative Fault-Tolerant Storage Scheme and Its Data Writing Optimization.

Fueled by the explosive growth of edge smart IoT devices, edge storage systems (ESS) have emerged as a new paradigm to support the efficient access of massive edge data. ESS can greatly alleviate the burden of cloud center and enhance the Quality of Experience (QoE) for users. However, despite the remarkable progress of ESS, it still faces the challenges of how to improve the systems fault tolerance ability and efficiency. Therefore, designing a secure and efficient text fault-tolerant storage scheme is urgent and indispensable. Unfortunately, existing text fault-tolerant schemes for ESS still retain various drawbacks, including: high edge storage overhead, hard to protect the edge data privacy and low data writing performance. Motivated by this, we propose a secure text cloud-edge collaborative fault-tolerant storage scheme and its data writing optimization method. Precisely, we first propose a Hierarchical text Cloud-Edge Collaborative Fault-Tolerant Storage (HCEFT) model to achieve system robustness, low edge storage overhead, and edge data privacy security. We further optimized the writing process of HCEFT by designing a data writing optimization method called ECWSS (Erasure Code data Writing method based on Steiner tree and SDN) to achieve a better text trade-off between the data writing time and traffic consumption. Finally, Comprehensive comparison and extensive experiments show that our scheme can achieve better data robustness, availability and security. Moreover, the writing optimization method can reduce 13%-67% data write time and 20%-62% network traffic consumption while providing better network load balance performance.