Towards a Secure Fragment Allocation of Files in Heterogeneous Distributed Systems

There is a growing demand for large-scale distributed storage systems to support resource sharing and fault tolerance. Although heterogeneity issues of distributed systems have been widely investigated, little attention has been given to security solutions designed for distributed storage systems with heterogeneous vulnerabilities. To address this issue, we design a Secure Fragment Allocation Scheme called S-FAS to improve security of a distributed system where storage sites have a wide variety of vulnerabilities. In the S-FAS approach, we integrate file fragmentation with the secret sharing technique in a distributed storage system with heterogeneous vulnerabilities. Storage sites in a distributed system are categarized into a variety of different server types based on vulnerability characteristics. Given a file and a distributed system, S-FAS allocates fragments of the file to a set of nodes with various vulnerability characteristics. Data confidentiality is preserved because fragments of a file are allocated to multiple types of storage nodes. We built storage assurance and dynamic assurance models to evaluate the quality of the security offered by S-FAS.