Big data cloud and the frontier of computer science and technology

The Special Issue of the Journal of Concurrency and Computation: Practice and experience presents the recent advances in cloud computing and software-defined network. Xu and colleagues focus on the big data storage problem in wireless sensor network with the nonuniform node distribution. To address this issue, they propose an efficient storage retrieval algorithm to estimate the real distribution of the sensor nodes and the real addresses of these nodes. Based on this algorithm, they further take the data redundancy among sensor nodes into account and exploit an efficient routing mechanism. Yao and colleagues study a VM migration problem with the goal of minimizing the total network cost, by making the decisions on which VM should be migrated and where the VM shall be migrated. Huang and colleagues study the performance degradation problem caused by the imbalanced data partition. They first propose a novel imbalance coefficient of data distribution. Tang and colleagues.propose a collaborative QoS prediction method with location-based data smoothing, for addressing the data sparsity issue and improving the QoS prediction accuracy.