Search results for "Scalability"
showing 10 items of 221 documents
Analyzing big datasets of genomic sequences: fast and scalable collection of k-mer statistics
2019
Abstract Background Distributed approaches based on the MapReduce programming paradigm have started to be proposed in the Bioinformatics domain, due to the large amount of data produced by the next-generation sequencing techniques. However, the use of MapReduce and related Big Data technologies and frameworks (e.g., Apache Hadoop and Spark) does not necessarily produce satisfactory results, in terms of both efficiency and effectiveness. We discuss how the development of distributed and Big Data management technologies has affected the analysis of large datasets of biological sequences. Moreover, we show how the choice of different parameter configurations and the careful engineering of the …
Scalable Monitoring System for Clouds
2013
Although cloud computing has become an important topic over the last couple of years, the development of cloud-specific monitoring systems has been neglected. This is surprising considering their importance for metering services and, thus, being able to charge customers. In this paper we introduce a monitoring architecture that was developed and is currently implemented in the EASI-CLOUDS project. The demands on cloud monitoring systems are manifold. Regular checks of the SLAs and the precise billing of the resource usage, for instance, require the collection and converting of infrastructure readings in short intervals. To ensure the scalability of the whole cloud, the monitoring system mus…
dSDiVN: A Distributed Software-Defined Networking Architecture for Infrastructure-Less Vehicular Networks
2017
In the last few years, the emerging network architecture paradigm of Software-Defined Networking (SDN), has become one of the most important technology to manage large scale networks such as Vehicular Ad-hoc Networks (VANETs). Recently, several works have shown interest in the use of SDN paradigm in VANETs. SDN brings flexibility, scalability and management facility to current VANETs. However, almost all of proposed Software-Defined VANET (SDVN) architectures are infrastructure-based. This paper will focus on how to enable SDN in infrastructure-less vehicular environments. For this aim, we propose a novel distributed SDN-based architecture for uncovered infrastructure-less vehicular scenari…
Geographical Routing for Delay Tolerant Encounter Networks
2007
Delay Tolerant Networks (DTNs) are intermittently connected networks, where direct end--to--end path between communicating nodes may never exist. To achieve eventual delivery some nodes must store messages and wait opportunity to forward them. In mobile environment, one of the most challenging problems for routing protocols is to decide, which nodes should store the message to achieve eventual delivery as quick as possible. Common approach is to propagate message into large group of nodes, hoping one of them will reach the destination. These solutions, however, are not very scalable as they generate plenty of extra load and traffic to network. Further more, message carriers have no means to…
Random Slicing: Efficient and Scalable Data Placement for Large-Scale Storage Systems
2014
The ever-growing amount of data requires highly scalable storage solutions. The most flexible approach is to use storage pools that can be expanded and scaled down by adding or removing storage devices. To make this approach usable, it is necessary to provide a solution to locate data items in such a dynamic environment. This article presents and evaluates the Random Slicing strategy, which incorporates lessons learned from table-based, rule-based, and pseudo-randomized hashing strategies and is able to provide a simple and efficient strategy that scales up to handle exascale data. Random Slicing keeps a small table with information about previous storage system insert and remove operations…
Modeling and Simulation of Network-on-Chip Systems with DEVS and DEUS
2013
Networks on-chip (NoCs) provide enhanced performance, scalability, modularity, and design productivity as compared with previous communication architectures for VLSI systems on-chip (SoCs), such as buses and dedicated signal wires. Since the NoC design space is very large and high dimensional, evaluation methodologies rely heavily on analytical modeling and simulation. Unfortunately, there is no standard modeling framework. In this paper we illustrate how to design and evaluate NoCs by integrating the Discrete Event System Specification (DEVS) modeling framework and the simulation environment called DEUS. The advantage of such an approach is that both DEVS and DEUS support modularity—the fo…
Per-flow signalling extension across DiffServ domains
2003
This paper describes a framework devised to extend per-flow admission control operation across Differentiated Services domains. Although the specific case of interoperability with RSVP is under discussion, our proposal can be easily adapted to other hop-by-hop signalling protocols. In our framework, DiffSery border routers accomplish three tasks. First, during the set-up phase, flows are mapped onto PHB groups on the basis of their QoS and traffic specifications. Second, signalling packets are tunnelled into IP packets marked as “probes”, where the “probe” marking is a DCSP value associated to the considered PHB Group. Third, when the flow set-up is complete, flow data packets are marked as…
Modèle dynamique multiniveau et holonique pour la simulation d'un système complexe à grande échelle avec environnement spatial : Application à la sim…
2020
Nowadays, with the emergence of connected objects and cars, road traffic systems become more and more complex and exhibit hierarchical behaviours at several levels of detail. The multilevel modeling approach is an appropriate approach to represent traffic from several perspectives. Multilevel models are also an appropriate approach to model large-scale complex systems such as road traffic. However, most of the multilevel models of traffic proposed in the literature are static because they use a set of predefined levels of detail and these representations cannot change during simulation. Moreover, these multilevel models generally consider only two levels of detail. Few works have been inter…
Efficient Graph Models for Retrieving Top-k News Feeds from Ego Networks
2012
A key challenge of web platforms like social networking sites and services for news feed aggregation is the efficient and targeted distribution of new content items to users. This can be formulated as the problem of retrieving the top-k news items out of the d-degree ego network of each given user, where the set of all users producing feeds is of size n, with n >> d >> k and typically k
Optimization on ports activation towards energy efficient data center networks
2018
Nowadays, Internet of thing including network support (i.e. checking social media, sending emails, video conferencing) requires smart and efficient data centers to support these services. Hence, data centers become more important and must be able to respond to ever changing service requirements and application demands. However, data centers are classified as one of the largest consumers of energy in the world. Existing topologies such as ScalNet improves the data center scalability while leading to enormous amounts of energy consumption. In this paper, we present a new energy efficient algorithm for ScalNet called Green ScalNet. The proposed topology strikes a compromise between maximizing …