L'objectiu del grup és la producció de contribucions rellevants en les àrees d'expertesa dels components del grup i la seva disseminació en revistes i conferències internacionals de prestigi reconegut. És voluntat del grup que les contribucions tinguin un impacte significatiu a llarg termini. La transferència de tecnologia és considerada com una conseqüència de l'excel·lència en la recerca i s'ha de portar a terme com un mitjà per incrementar l'impacte dels resultats, obtenir recursos per al grup i explorar nous temes per a la recerca en el futur.
Oda, T.; Sakamoto, S.; Barolli, A.; Spaho, E.; Barolli, L.; Xhafa, F. International journal of web and grid services Vol. 10, num. 4, p. 371-395 DOI: 10.1504/IJWGS.2014.064932 Data de publicació: 2014-01-01 Article en revista
Grid computing have emerged as scientific and technical work, where geographically distributed computers, are used to create virtual supercomputers of vast amount of computing capacity able to solve complex problems in less time than before. Thus, within the last years we have witnessed how grid computing has helped to achieve breakthroughs in meteorology, physics and other computing-intensive fields. Wireless Mesh Networks (WMNs) are particularly suited for providing the communications required for a robust, self-healing grid architecture. The good performance and operability of WMNs depend on placement of mesh routers nodes in the geographical deployment area. In this paper, we consider the grid topology and evaluate the performance of WMN-GA system for node placement problem in WMNs. We consider different distributions of mesh clients and different grid shapes. The simulation results show the effect of grid shapes in the performance of WMN-GA. The system performs better for normal distribution.
Xhafa, F.; Kolodziej, J.; Barolli, L.; Kolici, V.; Miho, R.; Takizawa, M. International journal of web and grid services Vol. 8, num. 2, p. 134-152 DOI: 10.1504/IJWGS.2012.048402 Data de publicació: 2012-08 Article en revista
Bessis, N.; Sotiriadis, S.; Xhafa, F.; POP, F.; Cristea , V. International journal of web and grid services Vol. 8, num. 2, p. 153-172 DOI: 10.1504/IJWGS.2012.048403 Data de publicació: 2012 Article en revista
Xhafa, F.; Paniagua, C.; Barolli, L.; Caballe, S. International journal of web and grid services Vol. 6, num. 2, p. 124-140 DOI: 10.1504/IJWGS.2010.033788 Data de publicació: 2010-06 Article en revista
Despite recent advances, grid and P2P systems remain difficult for many users to bring to real-world applications. One difficulty is the lack of schedulers for such systems. In this work, we consider the allocations of jobs to resources using batch mode methods. These methods are able to provide fast planning by exploring characteristics of distributed and highly heterogeneous systems. In evaluating these methods, four parameters of the system are measured: makespan, flowtime, resource utilisation and matching proximity. These methods were tested using the benchmark model of Braun et al. (2001) for distributed heterogeneous systems. Based on the computational results, we evaluate the performance of these methods with regard to the four considered metrics. Also, we evaluate the usefulness of batch methods when grid characteristics, such as degree of consistency of computing and heterogeneity of jobs and resources, are known in advance. We observe that batch mode methods are beneficial to grid scheduling services, for adaptively providing these services according to the grid infrastructure characteristics.
Computational Grids (CGs) are nowadays successfully responding to increasing needs for high computation power. A key issue in CGs is the scheduling, which demands for efficient methods. In this work, we consider the scheduling problem in immediate mode, in which jobs are allocated as soon as they arrive in the system. This type of scheduling arises in many grid-based applications, especially, in real-time applications. We have implemented five immediate scheduling methods and have measured their performance with respect to four parameters: makespan, flowtime, resource utilisation and matching proximity by using a simulation benchmark for heterogeneous distributed systems. The computational results showed the performance of the immediate scheduling methods and allowed us to evaluate the advantages of these methods if we knew in advance certain grid characteristics (consistency of computing, heterogeneity of jobs and resources). The usefulness of the presented methods in web and grid scheduling services is also discussed.