Search results for "Distributed computing"
showing 10 items of 622 documents
Bio-inspired security analysis for IoT scenarios
2020
Computer security has recently become more and more important as the world economy dependency from data has kept growing. The complexity of the systems that need to be kept secure calls for new models capable of abstracting the interdependencies among heterogeneous components that cooperate at providing the desired service. A promising approach is attack graph analysis, however, the manual analysis of attack graphs is tedious and error prone. In this paper we propose to apply the metabolic network model to attack graph analysis, using three interacting bio-inspired algorithms: topological analysis, flux balance analysis, and extreme pathway analysis. A developed framework for graph building…
Mapreduce in computational biology - A synopsis
2017
In the past 20 years, the Life Sciences have witnessed a paradigm shift in the way research is performed. Indeed, the computational part of biological and clinical studies has become central or is becoming so. Correspondingly, the amount of data that one needs to process, compare and analyze, has experienced an exponential growth. As a consequence, High Performance Computing (HPC, for short) is being used intensively, in particular in terms of multi-core architectures. However, recently and thanks to the advances in the processing of other scientific and commercial data, Distributed Computing is also being considered for Bioinformatics applications. In particular, the MapReduce paradigm, to…
Mapreduce in computational biology via hadoop and spark
2017
Bioinformatics has a long history of software solutions developed on multi-core computing systems for solving computational intensive problems. This option suffer from some issues solvable by shifting to Distributed Systems. In particular, the MapReduce computing paradigm, and its implementations, Hadoop and Spark, is becoming increasingly popular in the Bioinformatics field because it allows for virtual-unlimited horizontal scalability while being easy-to-use. Here we provide a qualitative evaluation of some of the most significant MapReduce bioinformatics applications. We also focus on one of these applications to show the importance of correctly engineering an application to fully exploi…
Ancillary Services in the Energy Blockchain for Microgrids
2019
The energy blockchain is a distributed Internet protocol for energy transactions between nodes of a power system. Recent applications of the energy blockchain in microgrids only consider the energy transactions between peers without considering the technical issues that can arise, especially when the system is islanded. One contribution of the paper is, thus, to depict a comprehensive framework of the technical and economic management of microgrids in the blockchain era, considering, for the first time, the provision of ancillary services and, in particular, of the voltage regulation service. When more PV nodes are operating in the grid, large reactive power flows may appear in the branches…
On the design of pervasive computing applications based on Bluetooth and a P2P concept
2006
As an example of implementing the pervasive computing, we developed an application framework to deploy an easy, spontaneous, and infrastructureless network. We selected the Bluetooth technology with the peer-to-peer (P2P) concept to develop an experimental application which enables peers to exchange their resources. Overall network architecture and the prototype application are presented. We selected a small test-bed and simulation to evaluate the overall performance and system behaviour. We measured and present our findings in term of the duration of inquiry procedure and the throughput, according to various experimental parameters such as physical distance between nodes and their speeds.
Detecting faulty wireless sensor nodes through Stochastic classification
2011
In many distributed systems, the possibility to adapt the behavior of the involved resources in response to unforeseen failures is an important requirement in order to significantly reduce the costs of management. Autonomous detection of faulty entities, however, is often a challenging task, especially when no direct human intervention is possible, as is the case for many scenarios involving Wireless Sensor Networks (WSNs), which usually operate in inaccessible and hostile environments. This paper presents an unsupervised approach for identifying faulty sensor nodes within a WSN. The proposed algorithm uses a probabilistic approach based on Markov Random Fields, requiring exclusively an ana…
Asynchronous Runtime Verification of Business Processes
2015
The authors propose a runtime verification mechanism for business processes. This mechanism allows verifying the correctness of business process execution and it runs in parallel with the base processes affecting them insignificantly. The authors have identified the case where the use of business process runtime verification is helpful and applicable. The verification mechanism monitors the business process execution and verifies compliance with the base process description. The verification mechanism prototype was developed and tested in real business processes, as well as limits of runtime verification overhead were evaluated.
Gossip
2019
Nowadays, a growing number of servers and workstations feature an increasing number of GPUs. However, slow communication among GPUs can lead to poor application performance. Thus, there is a latent demand for efficient multi-GPU communication primitives on such systems. This paper focuses on the gather, scatter and all-to-all collectives, which are important operations for various algorithms including parallel sorting and distributed hashing. We present two distinct communication strategies (ring-based and flow-oriented) to generate transfer plans for their topology-aware implementation on NVLink-connected multi-GPU systems. We achieve a throughput of up to 526 GB/s for all-to-all and 148 G…
Approximate Algorithm for Fast Capacity Provisioning in WANs with Trade-Off between Performance and Cost under Budget Constraint
2014
Due to the emergence of Software Defined Networking (SDN) with the idea of centralized control over computer networks, the Capacity and Flow Assignment Problem (CFA) may be approached in a classical non-distributed fashion in real-life scenarios. The question arises whether a heuristical approach to this NP-complete problem is of any use in practice.
Channel aggregation with guard-band in D-OFDM based CRNs: Modeling and performance evaluation
2016
Channel aggregation (CA) techniques can offer flexible channel allocation and improve overall system performance in multi-channel cognitive radio networks (CRNs). Although many CA techniques have been proposed and studied, the impact of guard-band on CA for channel access has not been addressed in-depth. In this paper, we study the guard-band allocation mechanisms in discontinuous-orthogonal frequency division multiplexing (D-OFDM) based CRNs, and investigate the impact of guard-band sharing on SU flows when CA is enabled. Continuous time Markov chain (CTMC) based models have been developed in order to investigate the stochastic behavior of PU and SU flows. Based on our mathematical analysi…