Service Level Agreements (SLAs) are currently one of the major research topics in Grid computing. Among many system components for supporting of SLA-aware Grid jobs, the SLA mapping module holds an important position and the capability of the mapping module depends on the runtime of the mapping algorithm. With the previously proposed algorithm to optimize the execution time of the workflow, the mapping module may develop into the bottleneck of the system if many requests come in during a short period of time. This paper presents a parallel mapping algorithm to optimize the execution time of the workflow, which can reduce the runtime of the mapping algorithm without reducing the quality of the mapping solutions. Performance measurements thereby deliver evaluation results showing the quality of the method. The speedup of the algorithms and the quality of the solutions are significantly improved when using eight CPUs comparing to using one CPU.

Energy efficiency is increasingly important for future information and communication technologies (ICT), because the increased usage of ICT, together with increasing energy costs and the need to reduce green house gas emissions call for energy-efficient technologies that decrease the overall energy consumption of computation, storage and communications. Cloud computing has recently received considerable attention, as a promising approach for delivering ICT services by improving the utilization of data centre resources. In principle, cloud computing can be an inherently energy-efficient technology for ICT provided that its potential for significant energy savings that have so far focused on hardware aspects, can be fully explored with respect to system operation and networking aspects. Thus this paper, in the context of cloud computing, reviews the usage of methods and technologies currently used for energy-efficient operation of computer hardware and network infrastructure. After surveying some of the current best practice and relevant literature in this area, this paper identifies some of the remaining key research challenges that arise when such energy-saving techniques are extended for use in cloud computing environments.

Service level agreements (SLAs) are currently one of the major research topics in grid computing. Among many system components for supporting of SLA-aware grid jobs, the SLA mapping module holds an important position. To find a mapping solution, the mapping algorithms have to search over a large search space. This situation leads to a compromise between the runtime of the algorithms and the quality of the mapping solutions. This paper presents a way of using parallelized mapping algorithms based on the proposed algorithms to improve the quality of the mapping solutions while maintaining the runtime of the mapping module. Performance measurements thereby deliver evaluation results showing the quality of the method.

Service Level Agreements (SLAs) is currently one of the major research topics in Grid Computing. Among many system components for the supporting of SLA-aware Grid-based workflow, the SLA mapping module receives important positions. Optimizing execution time is an important task of the mapping module as it helps in finding out afeasible solution when the Grid is busy or by eliminating the negative effects of the error. With the previously proposed algorithm for optimizing the execution time of the workflow, the mapping module may, when many requests come in a short period of time, become the bottleneck of the system. This paper presents a parallel mapping algorithm for optimizing the execution time of the workflow, which can cope with the problem. Performance measurementsdeliver evaluation results on the quality of the method.

Service level agreements (SLAs) are currently one of the major research topics in grid computing. Among many system components for supporting of SLA-aware Grid jobs, the SLA mapping module holds an important position and the capability of the mapping module depends on the runtime of the mapping algorithm. With the previously proposed mapping algorithm, the mapping module may develop into the bottleneck of the system if many requests come in during a short period of time. This paper presents a parallel mapping algorithm to map heavy communication SLA-based workflow onto Grid resources which can cope with the problem. Performance measurements thereby deliver evaluation results showing the quality of the method.

Service level agreements (SLAs) are currently one of the major research topics in Grid Computing. Among many system components for supporting of SLA-aware Grid-based workflows, the SLA mapping module receives an important position. Mapping light communication workflows is one main part of the mapping module. With the previously proposed mapping algorithm, the mapping module may become the bottleneck of the system when many requests come in a short period of time. This paper presents a parallel mapping algorithm for light communication SLA-based workflows, which can cope with the problem. Performance measurements deliver evaluation results on the quality of the method.

The error recovery mechanism receives an important position in the system supporting service level agreements (SLAs) for the grid-based workflow. If one sub-job of the workflow is late, a group of directly affected sub-jobs should be re-mapped in a way that does not affect the start time of other sub-jobs in the workflow and is as inexpensive as possible. With the distinguished workload and resource characteristics as well as the goal of the problem, this problem needs new method to be solved. This paper presents a mapping algorithm, which can cope with the problem. Performance measurements deliver good evaluation results on the quality and efficiency of the method.

Service level agreements (SLAs) are currently one of the major research topics in grid computing resulting in a language definition for specification of SLAs and corresponding system architectures. However, previous work solely addresses problems for monolithic grid jobs. The description of a workflow (job flow) considers characteristics of correlated sub-jobs, thus the problem grows more complex in terms of management, SLA specification, fault reaction etc. Therefore, this paper presents system architecture to ensure SLAs for grid-based workflows and a corresponding language for the SLA specification.