Cloud computing is the new trend in service delivery, and promises cost savings and agility for the customers. However, some challenges still remains to be solved before widespread use can be seen. This is especially relevant for enterprises, which currently lack the necessary assurance for moving their critical data and applications to the cloud. The cloud SLAs are simply not good enough. This...

Novel energy-aware cloud management methods dynamically reallocate computation across geographically distributed data centers to leverage regional electricity price and temperature differences. As a result, a managed virtual machine (VM) may suffer occasional downtimes. Current cloud providers only offer high availability VMs, without enough flexibility to apply such energyaware management. In ...

Cloud computing changed the way of computing as utility services offered through public network. Selecting multiple providers for various computational requirements improves performance and minimizes cost of cloud services than choosing a single cloud provider. Federated cloud improves scalability, cost minimization, performance maximization, collaboration with other providers, multi-site deplo...

The obligations that telecommunications providers have with their customers are nowadays clearly specified in SLA contracts. The offered availability during the contract period is one of the most relevant variables in SLAs. Modeling accurately the transient solution posed by the need of considering the interval availability is still an open challenge. A common policy taken to make simpler model...

This study is carried out in the framework of SUCCESS (Smaller Urban Communities in CIVITAS for Environmentally Sustainable Solutions), an European project funded by the European Commission under the CIVITAS program. These demonstration projects provide a means of testing out a wide range of projects in a number of cities and the results of the evaluation will assist in showing which were succe...

Cloud computing is a new paradigm and innovation in the technology service delivery. It is utilized for IT-enabled value creation. The capex-free nature of cloud service delivery renders it very attractive to many SMEs. But it is saddled with multi-tenancy issues; prominent under this study are concerns of privacy, trust and availability. How do end-users trust providers with their sensitive da...

The scientific applications of the fourth paradigm [1] of science deal with large amounts of data, which can be stored in various storage devices or systems taking into account the possibility of sharing and archiving. Some of the requirements posed to those storage systems may concern the Quality of Service (QoS) aspects. Examples of such requirements are: specifying the minimal data transfer ...

Previous research has addressed the scalability and availability issues associated with the construction of cluster-based network services. This paper studies the clustering of replicated services when the persistent service data is frequently updated. To this end we propose Neptune, an infrastructural middleware that provides a flexible interface to aggregate and replicate existing service mod...

this paper presents a new formulation for warehouse inventory management in a stochastic situation. the primary source of this formulation is derived from fp model, which has been proposed by fletcher and ponnambalam for reservoir management. the new proposed mathematical model is based on the first and the second moments of storage as a stochastic variable. using this model, the expected value...