Search results for "Performance evaluation"
showing 10 items of 44 documents
A reconfigurable platform for evaluating the performance of QoS networks
2010
Nowadays, high performance System and Local Area Networks (SAN/LAN) have to serve heterogeneous traffic consisting of information flows with different bandwidth and latency requirements. This makes it necessary to provide Quality of Service (QoS) and optimize the design of network components. In this paper we present a hardware tool designed to analyze the performance of QoS networks, under given traffic conditions and server models. In particular, a reprogrammable multimedia traffic Generator/Monitor platform has been built. This permits prototyping the communication system of a high speed LAN/SAN on a single FPGA device. Hence, it can be used at design to produce more efficient devices. T…
QoS Multi-tree Based Routing Protocol for Inter-mesh Infrastructure Communications
2016
Part 5: Network Protocols; International audience; Quality of service (QoS) in wireless mesh networks (WMN) is an active area of research, which is driven by the increasing demand for real-time and multimedia applications, such as VoIP (Voice over IP) and VoD (Video on Demand). In this paper, we propose a QoS multi-tree based routing protocol for wireless mesh environments, named Inter-Mesh Infrastructure Proactive Routing (IMPR). It is a proactive multi-tree routing protocol enabling QoS guarantee for communications from/towards the Internet network through the Mesh Gateway (MG) of the mesh infrastructure. We describe and analyze the simulation results of different scenarios conducted on t…
QoS Based Routing Protocol for Intra-Mesh Infrastructure Communications
2015
International audience; Mesh Networks (WMNs) have been considered as a promising alternative to conventional wired networks, thanks to its flexibility and easy deployment. Thus, to ensure a satisfying level of QoS guarantees for real-time and streaming applications such as Voice over IP (VoIP) and Video on Demand (VoD), we propose a novel QoS based routing protocol for wireless mesh environments, called Hybrid QoS Mesh Routing (HQMR), jointly with a clustering algorithm to enhance scalability issues within the mesh infrastructure. HQMR is composed of two routing sub-protocols: a reactive routing sub-protocol for intra-infrastructure communications and a proactive QoS based multi-tree routin…
Self-configuring multipath intra-mesh infrastructure QoS based routing
2016
International audience; Multi-path routing concept was largely exploited in wireless networks to provide benefits such as fault tolerance, load balancing, performance improvement in terms of latency, etc. In this paper, we propose a multi-path routing based protocol named MP-IMRR (Multi-path Intra-Mesh infrastructure Routing protocol) to improve our previously defined QoS based routing protocol for wireless mesh networks (i.e. IMRR). MP-IMRR is defined in order to achieve better reactivity and faster recovery from eventual route failures than the IMRR protocol by adopting the backup routes concept. Besides, given the complexity increase while considering network management systems, we adopt…
Performance Analysis in Spatially Correlated IEEE 802.11 Networks
2012
Wireless mesh networks are difficult to be characterized, especially under multi-hop traffic streams. The problem is that the local view of the channel and the correlation between the buffers of consecutive nodes in a stream path make complicated the identification of the contention level perceived by each station along the time. Such a figure is used in the models based on the so called decoupling assumption for evaluating the final scheduling of simultaneous channel access grants. In this paper we propose a simplified mesh network model focused on capturing the correlation due to the network topology and traffic routes rather than the access protocol state at each node. To this purpose, w…
A Geographical Self-Organizing Approach for Vehicular Networks
2012
Cooperative vehicular networks have always been considered as the perfect way to bring more comfort to the passengers and more safety to the human life. Thus, research community and governmental organizations are interested to study and deploy these networks. The vehicular networks principle is connecting vehicles to each other and to existing infrastructure. However, their industrialization faces some challenges: (i) high mobility, (ii) frequently partitioned network, (iii) geographically constrained topology, and (iv) scalability. Therefore, in contrast to traditional networks, vehicular network protocols focus on both achieving adequate QoS level and reducing overhead. Achieving these tw…
Experimental Performance Evaluation of Cloud-Based Analytics-as-a-Service
2016
An increasing number of Analytics-as-a-Service solutions has recently seen the light, in the landscape of cloud-based services. These services allow flexible composition of compute and storage components, that create powerful data ingestion and processing pipelines. This work is a first attempt at an experimental evaluation of analytic application performance executed using a wide range of storage service configurations. We present an intuitive notion of data locality, that we use as a proxy to rank different service compositions in terms of expected performance. Through an empirical analysis, we dissect the performance achieved by analytic workloads and unveil problems due to the impedance…
Integration of a structural features-based preclassifier and a man-machine interactive classifier for a fast multi-stroke character recognition
2003
A transputer-based parallel machine for handwritten character recognition is proposed. An algorithm based on structural features and on a tree classifier was used to accomplish the pre-classification of the unknown sample in order to speed up the recognition process. The algorithm for the final classification is based on the description of the strokes through Fourier descriptors. The learning phase is accomplished through a man-machine interactive process. The proposed system can expand its knowledge base. A special representation of this knowledge base is proposed in order to record a great amount of data in a suitable way. A fast multistroke handwritten isolated character recognition syst…
SHARP: Environment and Person Independent Activity Recognition with Commodity IEEE 802.11 Access Points
2022
In this article we present SHARP, an original approach for obtaining human activity recognition (HAR) through the use of commercial IEEE 802.11 (Wi-Fi) devices. SHARP grants the possibility to discern the activities of different persons, across different time-spans and environments. To achieve this, we devise a new technique to clean and process the channel frequency response (CFR) phase of the Wi-Fi channel, obtaining an estimate of the Doppler shift at a radio monitor device. The Doppler shift reveals the presence of moving scatterers in the environment, while not being affected by (environment-specific) static objects. SHARP is trained on data collected as a person performs seven differe…
Radiation Hardness Assurance Through System-Level Testing: Risk Acceptance, Facility Requirements, Test Methodology, and Data Exploitation
2021
International audience; Functional verification schemes at a level different from component-level testing are emerging as a cost-effective tool for those space systems for which the risk associated with a lower level of assurance can be accepted. Despite the promising potential, system-level radiation testing can be applied to the functional verification of systems under restricted intrinsic boundaries. Most of them are related to the use of hadrons as opposed to heavy ions. Hadrons are preferred for the irradiation of any bulky system, in general, because of their deeper penetration capabilities. General guidelines about the test preparation and procedure for a high-level radiation test ar…