Search results for "Distributed computing"
showing 10 items of 622 documents
A Web-Based Coordination Infrastructure for Grid Collective Services
2004
Virtual Organizations (VO) consisting of heterogeneous institutions and individuals that share resources dynamically and in a coordinated way to support collaborative problem-solving are emerging in many fields. Consequently, new types of distributed infrastructures known as Grids have been proposed to cope with these new sharing requirements. Grids offer sets of collective services to support collaborative tasks which are distributed in nature and need asynchronous communication. Existing approaches to this problem lack of flexibility, adaptability and are tightly bound to the collective service that is provided. We present here a generic event model to build collective services that requi…
Mobile agents and grid computing
2004
Publisher Summary This chapter describes mobile agents as an effective solution for grid service provision. A short overview is first introduced on the grid paradigm and the most known research activities in the field. Then, mobile agents are discussed and a comparison with the remote procedure call (RPC) method is made as far as the most effective solution to minimize network overload and fault occurrences is concerned. The common feature of all grid architectures is a coordinated and controlled resource sharing between the members of a dynamic multi-institutional virtual community. Community members agree on a set of sharing rules and permissions, by which resources to be shared and membe…
Integrating Variability Management in Data Center Networks
2017
International audience; Data centers have an important role in supporting cloud computing services (i.e. checking social media, sending emails, video conferencing,..). Hence, data centers topologies design became more important and must be able to respond to ever changing service requirements and application demands. An ultimate challenge in this research is the design of data center network that interconnects the massive number of servers, and provides efficient and fault-tolerant routing algorithm. Several topologies such as DCell, FlatNet and ScalNet have been proposed. However, these topologies generally seek to improve the scalability without taking into consideration the energy usage …
A genetic approach for adding QoS to distributed virtual environments
2007
Distributed virtual environment (DVE) systems have been designed last years as a set of distributed servers. These systems allow a large number of remote users to share a single 3D virtual scene. In order to provide quality of service in a DVE system, clients should be properly assigned to servers taking into account system throughput and system latency. The latter one is composed of both network and computational delays. This highly complex problem is known as the quality of service (QoS) problem. In this paper, we study the implementation of a genetic algorithm (GA) for solving the QoS problem in DVE systems. Performance evaluation results show that, due to its ability of both finding goo…
Producing Routing Systems Flexibly Using a VRP Metamodel and a Software Product Line
2012
Routing problems occur in a wide variety of situations. Due to the heterogeneity of cases we do not yet know how to manage the complexity of addressing all the relevant aspects in logistic planning and solving the variety of different problem types in a cost-efficient way. In the last decade, we have witnessed an emergence of systematic approach into managing variation within a set of related software systems. This paper presents an application of these advances from software engineering into vehicle routing: we suggest the construction of a higher-level (meta-) model of routing problems and the application of a software product line approach. The proposed approach results in a flexible pro…
Intelligent Energy Management System
2009
Energy management is nowadays a subject of great importance and complexity. It consists in choosing among a set of sources able to produce energy that will give energy to a set of loads by minimising losses and costs. The sources and loads are heterogeneous, distributed and the reaction of the system, the choice of sources, must be done in real-time to avoid power outage. The goal of this paper is to present a system able to self-regulate a heterogeneous set of power sources and loads organised as a coherent group of entities that is called micro-grid, in order to optimize several criteria such as: cost and efficiency. This system is based upon the Multi-Agent Systems paradigm. Each micro-g…
The quest for bandwidth estimation techniques for large-scale distributed systems
2010
In recent years the research community has developed many techniques to estimate the end-to-end available bandwidth of an Internet path. This important metric can be potentially exploited to optimize the performance of several distributed systems and, even, to improve the effectiveness of the congestion control mechanism of TCP. Thus, it has been suggested that some existing estimation techniques could be used for this purpose. However, existing tools were not designed for large-scale deployments and were mostly validated in controlled settings, considering only one measurement running at a time. In this paper, we argue that current tools, while offering good estimates when used alone, migh…
Coexistence between IEEE802.15.4 and IEEE802.11 through cross-technology signaling
2017
When different technologies use the same frequency bands in close proximity, the resulting interference typically results in performance degradation. Coexistence methods exist, but these are often technology specific and requiring technology specific interference detection methods. To remove the root cause of the performance degradation, devices should be able to negotiate medium access even when using different technologies. To this end, this paper proposes an architecture that allows crosstechnology medium access by means of a Time Division Multiple Access (TDMA) scheme. In order to achieve cross-technology synchronization, which is required for the TDMA solution, an energy pattern beacon…
Coloring-based resource allocations in ad-hoc wireless networks
2011
It is well known that CSMA/CA protocols exhibit very poor performance in case of multi-hop transmissions, because of inter-link interference due to imperfect carrier sensing. We propose to control such an interference by preallocating temporal slots in which different sets of network nodes are allowed to contend for the channel access. The approach is based on distributed coloring algorithms with limited signaling overhead that can be customized as a function of the network topology and traffic load.
Logical Consensus for Distributed Network Agreement
2008
In this paper we introduce a novel consensus mechanism where agents of a network are able to share logical values, or Booleans, representing their local opinions on e.g. the presence of an intruder or of a fire within an indoor environment. Under suitable joint conditions on agents? visibility and communication capability, we provide an algorithm generating a logical linear consensus system that is globally stable. The solution is optimal in terms of the number of messages to be exchanged and the time needed to reach a consensus. Moreover, to cope with possible sensor failure, we propose a second design approach that produces robust logical nonlinear consensus systems tolerating a maximum n…