Special Issue: Cloud Computing 2011

This special issue of Journal of Computer and System Sciences is devoted to papers on Cloud Computing based on WMSC09 – The 1st International Workshop on Workflow Management in Service and Cloud Computing held in Chengdu, China in August 10–12, 2009, and WMSC10 – The 2rd International Workshop on Workflow Management in Service and Cloud Computing held in Hongkong, China in December 11–13, 2010. Cloud computing is positioning itself as a new emerging platform for delivering information infrastructures and resources as IT services. Customers (enterprises or individuals) can then provision and deploy these services in a pay-as-you-go fashion and in a convenient way while saving huge capital investment in their own IT infrastructures. It falls in the area of parallel and distributed computing and the area of computer modelling of complex systems in the context of Journal of Computer and System Sciences. It is becoming a dedicated area and has evoked a high degree of interest internationally with many challenges such as security and privacy remaining open. After a few years’ efforts and arguments since 2007, cloud computing is now really coming to the stage both in industry and in academia with huge potential applications in business. As such, this special issue is a timely and strategic one in the journey of this area. The eight papers in this special issue offer a view from different perspectives on current research in cloud computing. The first paper is related to resource management and Quality of Service provision in cloud computing and touches the service models of cloud computing of SaaS, IaaS and PaaS. The paper proposes innovative admission control and scheduling algorithms for SaaS providers to effectively utilise public cloud resources to maximise profit by minimising cost and improving customer satisfaction level. The second paper focuses on user job execution in cloud computing environment. The paper proposes a workflow system architecture which enforces QoS for the simultaneous execution of multiple scientific workflows over cloud environment. The third paper is related to service invocation cross-platform in cloud computing environment. It proposes a QoS-aware service composition with the invocation of service across platforms in cloud computing environment. The fourth paper addresses federation of multiple clouds. It proposes a federated architecture which can combine multiple clouds together to form inter-cloud platform. The fifth paper focuses on the security issue in cloud computing. It proposes a novel efficient Distributed Multiple Replicas Data Possession Checking (DMRDPC) scheme to secure multiple replicas. The sixth paper is about server side privacy protection in cloud computing environment. It presents a policy based authorisation infrastructure that a cloud provider can run as an infrastructure service for its users. The seventh paper is about client side privacy protection in cloud computing environment. It proposes a historical probability based noise generation strategy for client side privacy protection in cloud computing environment. The eighth paper is related to MapReduce – a popular programming model originally proposed by Google for large-scale parallel data processing in cloud computing environment. It proposes an adaptive MapReduce framework, called P2P-MapReduce, which exploits a peer-to-peer model to manage node churn, master failures, and job recovery in a decentralised but effective way, so as to provide a more reliable MapReduce middleware that can be effectively exploited in dynamic cloud infrastructures. While the authors were invited to submit their papers to this special issue, all papers went through the standard refereeing procedures of this journal. We would like to thank the authors and referees for their help in making timely publication of this special issue possible. This issue could not have been produced without them.