Abstract
As more and more enterprises and personal users move their data to cloud storage, performance and cost consumption are getting more and more important for user. Cloud service provides global infrastructures by building data centers at different locations. In addition, single replica can not handle user’s global access behaviors such as changing access pattern or sharing data across continents. A single platform which is capable to combine all of the cloud storage in different locations and benefit from global infrastructure to solve the global access problem is necessary. Furthermore, where should the replica be stored to make the system has higher performance and lower cost consumption should also be considered. In this paper, we develop a federated cloud storage system that combines multiple cloud storage into a single platform, and propose a dynamic replica placement algorithm that can decide the best replica placement according to different workloads and user behaviors.