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In many distributed computing systems, aspects related to security are getting more and more relevant. Security is ubiquitous and could not be treated as a separated problem or a challenge. In our opinion it should be considered in the context of resource management in distributed computing environments like Grids and Clouds, e.g. scheduled computations can be much delayed because of cyber-attacks, inefficient infrastructure or users valuable and sensitive data can be stolen even in the process of correct computation. To prevent such cases there is a need to introduce new evaluation metrics for resource management that will represent the level of security of computing resources and more broadly distributed computing infrastructures. In our approach, we have introduced a new metric called reputation, which simply determines the level of reliability of computing resources from the security perspective and could be taken into account during scheduling procedures. The new reputation metric is based on various relevant parameters regarding cyber-attacks (also energy attacks), administrative activities such as security updates, bug fixes and security patches. Moreover, we have conducted various computational experiments within the Grid Scheduling Simulator environment (GSSIM) inspired by real application scenarios. Finally, our experimental studies of new resource management approaches taking into account critical security aspects are also discussed in this paper.

A method of solving the scheduling problems associated with multi-mode resource constrained project, which generate positive discounted cash flows, is presented. Four different payment models are considered for the project. Simulated annealing and tabu search are suggested for solving the problems associated with scheduling.

Three local search metaheuristics were evaluated in terms of addressing discrete-continuous scheduling problems. Computational experiment revealed that the tabu search, the simulated annealing and the genetic algorithm were able to outperform the random sampling technique. The tabu search, meanwhile, was found to be the best metaheuristic in terms of generating the biggest number of optimal solutions and the smallest optimum deviation for all problem sizes.

In this paper, we consider the problem of scheduling network tasks that have to be performed in a given computer network. Each network task consists of the transmission of data files between two nodes of the network and has to be performed in an a priori known time window in such a way that the energy consumed by the network equipment during the transmission of all the considered tasks is minimized. The entire mathematical model of this scheduling problem is proposed. Some results of computational experiments are also presented to show energy savings achieved through implementation of the proposed model in the interdata center network. [ABSTRACT FROM AUTHOR]

We consider the problem of scheduling preemptable, dependent tasks on parallel, identical machines to minimize the makespan. The computational complexity of this problem remains open if the number of machines is fixed and larger than 2. The aim of this paper is to compare two heuristic algorithms on a basis of a computational experiment. The solutions generated by the heuristics are compared with optimal solutions obtained by a branch-and-bound algorithm. Computational results show that the heuristic based on node ordering finds optimal schedules for 99.9% of instances with the maximum relative deviation from optimum of 4.8%. [ABSTRACT FROM AUTHOR]