39 research outputs found

    A new QoS Routing Architecture in NGI

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    After a thorough understanding of the relevant research knowledge and the key theory of NGN, I describe the research objectives and the recent development of the QoS routing in this thesis. QoS routing is regarded as the key part in the problem of the next generation of integrated-service network. A new routing algorithm is put forward in this thesis, which is better than OSPF in some aspects. As for the experiment, NS2 is chosen as the simulation environment, and some other experimental results are also included to manifest its strongpoint. The development and requirement of NGN is described in Chapter One; The definition and types of routing and the basic theories of QoS routing are described in Chapter Two; The development and research method of QoS are focused in Chapter Three. The new routing algorithm and simulation is proposed in Chapter Four

    SOMM: A New Service Oriented Middleware for Generic Wireless Multimedia Sensor Networks Based on Code Mobility

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    Although much research in the area of Wireless Multimedia Sensor Networks (WMSNs) has been done in recent years, the programming of sensor nodes is still time-consuming and tedious. It requires expertise in low-level programming, mainly because of the use of resource constrained hardware and also the low level API provided by current operating systems. The code of the resulting systems has typically no clear separation between application and system logic. This minimizes the possibility of reusing code and often leads to the necessity of major changes when the underlying platform is changed. In this paper, we present a service oriented middleware named SOMM to support application development for WMSNs. The main goal of SOMM is to enable the development of modifiable and scalable WMSN applications. A network which uses the SOMM is capable of providing multiple services to multiple clients at the same time with the specified Quality of Service (QoS). SOMM uses a virtual machine with the ability to support mobile agents. Services in SOMM are provided by mobile agents and SOMM also provides a t space on each node which agents can use to communicate with each other

    ENERGY AWARE TRAFFIC ENGINEERING IN WIRED COMMUNICATION NETWORKS

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    The reduction of power consumption in communication networks has become a key issue for both the Internet Service Providers (ISP) and the research community. Ac- cording to different studies, the power consumption of Information and Communication Technologies (ICT) varies from 2% to 10% of the worldwide power consumption [1,2]. Moreover, the expected trends for the future predict a notably increase of the ICT power consumption, doubling its value by 2020 [2] and growing to around 30% of the worldwide electricity demand by 2030 according to business-as-usual evaluation scenarios [15]. It is therefore not surprising that researchers, manufacturers and network providers are spending significant efforts to reduce the power consumption of ICT systems from dif- ferent angles. To this extent, networking devices waste a considerable amount of power. In partic- ular, their power consumption has always been increased in the last years, coupled with the increase of the offered performance [16]. Actually, power consumption of network- ing devices scales with the installed capacity, rather than the current load [17]. Thus, for an ISP the network power consumption is practically constant, unrespectively to traffic fluctuations. However, actual traffic is subject to strong day/night oscillations [3]. Thus, many devices are underutilized, especially during off-peak hours when traffic is low. This represents a clear opportunity for saving energy, since many resources (i.e., routers and links) are powered on without being fully utilized. In this context, resource consolidation is a known paradigm for the reduction of the power consumption. It consists in having a carefully selected subset of network devices entering a low power state, and use the rest to transport the required amount of traffic. This is possible without disrupting the Quality of Service (QoS) offered by the network infrastructure, since communication networks are designed over the peak foreseen traffic request, and with redundancy and over-provisioning in mind. In this thesis work, we present different techniques to perform resource consolida- tion in backbone IP-based networks, ranging from centralized solutions, where a central entity computes a global solution based on an omniscient vision of the network, to dis- tributed solutions, where single nodes take independent decisions on the local power- state, based solely on local knowledge. Moreover, different technological assumptions are made, to account for different possible directions of the network devices evolutions, ranging from the possibility to switch off linecard ports, to whole network nodes, and taking into account different power consumption profiles

    Réseaux ad hoc : système d'adressage et méthodes d'accessibilité aux données

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    RÉSUMÉ Au cours de la dernière décennie, un nouveau type de réseaux sans fil a suscité un grand intérêt dans la communauté scientifique: ce sont les réseaux ad hoc. Ils existent sous la variante des réseaux mobiles ad hoc (MANET), et des réseaux de capteurs sans fil (RCSF). Les réseaux mobiles ad hoc sont constitués de noeuds mobiles qui communiquent les uns avec les autres sans l‘aide d‘une d'infrastructure centralisée. Les noeuds se déplacent librement et sont soumis à des déconnexions fréquentes en raison de l'instabilité des liens. Cela a pour conséquence de diminuer l'accessibilité aux données, et de modifier la façon dont les données sont partagées dans le réseau. Comparable aux réseaux MANET, un RCSF est composé d'un ensemble d'unités de traitements embarquées, appelées capteurs, communiquant via des liens sans fil et dont la fonction principale est la collecte de paramètres relatifs à l'environnement qui les entoure, telles que la température, la pression, ou la présence d'objets. Les RCSF diffèrent des MANET de par le déploiement à grande échelle des noeuds, et trouvent leur application dans diverses activités de la société, tels les processus industriels, les applications militaires de surveillance, l'observation et le suivi d'habitat, etc. Lorsqu‘un grand nombre de capteurs sont déployés avec des dispositifs d'actionnement appelés acteurs, le RCSF devient un réseau de capteurs et d‘acteurs sans fil (RCASF). Dans une telle situation, les capteurs collaborent pour la détection des phénomènes physiques et rapportent les données afférentes aux acteurs qui les traitent et initient les actions appropriées. De nombreux travaux dans les RCSF supposent l'existence d'adresses et d'infrastructures de routage pour valider leurs propositions. Cependant, l‘allocation d‘adresses et le routage des données liées aux événements détectés dans ces réseaux restent des défis entiers, en particulier à cause du nombre élevé de capteurs et des ressources limitées dont ils disposent. Dans cette thèse, nous abordons le problème de l'accessibilité aux données dans les MANET, et les mécanismes d‘adressage et de routage dans les RCSF de grande taille.----------ABSTRACT During the last decade, a new type of wireless networks has stirred up great interest within the scientific community: there are ad hoc networks. They exist as mobile ad hoc networks (MANET), and wireless sensor (WSN). The mobile ad hoc networks consist of mobile nodes that communicate with each other without using a centralized infrastructure. The nodes move freely and are subject to frequent disconnections due to links instability. This has the effect of reducing data accessibility, and change the way data are shared across the network. Similar MANET networks, a WSN consists of a set of embedded processing units called sensors that communicate with each other via wireless links. Their main function is the collection of parameters relating to the environment around them, such as temperature, pressure, motion, video, etc. WSNs differ from the MANETs due to the large scale deployment of nodes, and are expected to have many applications in various fields, such as industrial processes, military surveillance, observation and monitoring of habitat, etc. When a large number of sensors which are resource-impoverished nodes are deployed with powerful actuation devices, the WSN becomes a Wireless Sensor and Actor Network (WSAN). In such a situation, the collaborative operation of sensors enables the distributed sensing of a physical phenomenon, while actors collect and process sensor data to perform appropriate action. Numerous works in WSN assumes the existence of addresses and routing infrastructure to validate their proposals. However, assigning addresses and delivering detected events remains highly challenging, specifically due to the sheer number of nodes. In this thesis, we address the problem of data accessibility in MANET, and that of addressing and routing in large scale WSN. This involves techniques such as data caching and replication to prevent the deterioration of data accessibility. The addressing system in WSN includes a distributed address allocation scheme and a routing infrastructure for both actors and sensors. Moreover, with the birth of the multimedia sensors, the traffic may be mixed with time sensitive packets and reliability-demanding packets. For that purpose, we also address the problem of providing quality of service (QoS) in the routing infrastructure for WSN

    Maximizing Broadcast and Multicast Traffic Load through Link-Rate Diversity in Wireless Mesh Networks

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    This paper studies some of the fundamental challenges and opportunities associated with the network-layer broadcast and multicast in a multihop multirate wireless mesh network (WMN). In particular, we focus on exploiting the ability of nodes to perform link-layer broadcasts at different rates (with correspondingly different coverage areas). We first show how, in the broadcast wireless medium, the available capacity at a mesh node for a multicast transmission is not just a function of the aggregate pre-existing traffic load of other interfering nodes, but intricately coupled to the actual (sender, receiver) set and the link-layer rate of each individual transmission. We then present and study four alternative heuristic strategies for computing a broadcast tree that not only factors in a flow’s traffic rate but also exploits the wireless broadcast advantage (WBA). Finally, we demonstrate how our insights can be extended to multicast routing in a WMN, and present results that show how a tree-formation algorithm that combines contention awareness with transmission rate diversity can significantly increase the total amount of admissible multicast traffic load in a WMN.

    Routage et gestion de la mobilité dans les réseaux personnels

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    L'objectif de cette thèse est d'étudier des méthodes et des stratégies efficaces pour le routage et la gestion de la mobilité dans le cadre des réseaux personnels. Dans un premier temps, nous proposons le cadre de nos études: Personal Ubiquitous Environments (PUE). Un PUE est constitué d'un ensemble d'utilisateurs ayant des terminaux disposant d'interfaces réseau hétérogènes, et dont l'objectif est de mettre en oeuvre des mécanismes de coopération et de partage des ressources de manière totalement distribuée. Dans ce cadre, la thèse a proposé des solutions innovantes contribuant à améliorer la communication inter et intra réseau personnels. La première contribution porte sur le protocole PNRP (Personal Network Routing Protocol) dont le but est de développer un routage à base de politiques (policy-based routing) pour les environnements personnels. La seconde, intitulée ADD (Adaptive Distributed gateway Discovery), est un mécanisme totalement distribué pour la découverte de multiples chemins vers une passerelle vers un réseau opéré. De plus, étant donné que ces environnements sont hétérogènes par leurs compositions (réseaux d'accès, terminaux ...), une architecture de gestion de la mobilité qui permet une gestion unifiée de la localisation et de la mobilité sans coutures appliquant lénsemble des noeuds a également été traitée. Les résultats d'évaluation par simulation démontrent l'applicabilité et léfficacité des ces protocoles.The aim of this thesis is to investigate methods and strategies for efficient routing and mobility management in personal environments. The concept of Personal Ubiquitous Environments (PUE) is introduced which accommodates heterogeneous devices and access networks of different users and sustain the notion of sharing resources in a distributed manner. A prerequisite for achieving the resource (devices, networks) sharing in personal environments is the deployment of suitable communication protocols which establish efficient multi-hop routes betweens the devices of the PUE. Personal Network Routing Protocol (PNRP) has been developed to perform policy-based routing in personal environments. Moreover, in certain personal networking scenarios, the infrastructure network components (i.e. gateways) are more than one-hop distance from the user's devices; Adaptive Distributed gateway Discovery (ADD) protocol is thereby proposed to efficiently discover the multi-hop routes towards the gateway in a totally distributed manner. All the more, since the personal environments regroups heterogeneous access networks, an efficient mobility management architecture is proposed which offers unified location management and seamless handover experience to dynamic personal nodes. The proposed protocols are assessed by means of numerous communication scenarios; the simulation results demonstrate the applicability of the proposed protocols

    Energy aware traffic engineering in wired communication networks

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    Que le phénomène découle d une prise de conscience des conséquences sur l environnement, d une opportunité économique ou d une question de réputation et de commerce, la réduction des émissions de gaz à effets de serre est récemment devenue un objectif de premier plan. Les individus, les entreprises et les gouvernements effectuent un effort important pour réduire la dépense énergétique de multiples secteurs d activité. Parallèlement, les technologies de l information et de la communication sont de plus en plus présentes dans la plupart des activités humaines et l on a estimé que 2% des émissions de gaz à effets de serre pouvaient leur être attribuées, cette proportion atteignant 10 % dans les pays fortement industrialisés [1, 2]. Si ces chiffres paraissent raisonnables aujourd hui, ils sont certainement appelés à croître à l avenir. À l heure du cloud computing, les infrastructures de calcul et de communication demandent de plus en plus de performance et de disponibilité et imposent l utilisation de matériels puissants et engendrant une consommation d énergie importante du fait de leur fonctionnement direct, mais aussi à cause du refroidissement qu ils nécessitent. En outre, les contraintes de disponibilité imposent une conception d architectures redondantes et dimensionnées sur une charge crête. Les infrastructures sont donc souvent sous-utilisées et adapter leur niveau de performance à la charge effectivement constatée constitue une piste d optimisation prometteuse à divers niveaux. Si l on adopte un strict point de vue environnemental, l objectif du Green Networking consiste à réduire le volume d émissions de gaz à effets de serre dues au processus de communication. L utilisation de sources d énergie renouvelables ou d électronique de faible consommation (par exemple asynchrone) constituent des pistes évidentes d amélioration.The reduction of power consumption in communication networks has become a key issue for both the Internet Service Providers (ISP) and the research community. Ac- cording to different studies, the power consumption of Information and Communication Technologies (ICT) varies from 2% to 10% of the worldwide power consumption [1, 2]. Moreover, the expected trends for the future predict a notably increase of the ICT power consumption, doubling its value by 2020 [2] and growing to around 30% of the worldwide electricity demand by 2030 according to business-as-usual evaluation scenarios [15]. It is therefore not surprising that researchers, manufacturers and network providers are spending significant efforts to reduce the power consumption of ICT systems from dif- ferent angles. To this extent, networking devices waste a considerable amount of power. In partic- ular, their power consumption has always been increased in the last years, coupled with the increase of the offered performance [16]. Actually, power consumption of network- ing devices scales with the installed capacity, rather than the current load [17]. Thus, for an ISP the network power consumption is practically constant, unrespectively to traffic fluctuations. However, actual traffic is subject to strong day/night oscillations [3]. Thus, many devices are underutilized, especially during off-peak hours when traffic is low. This represents a clear opportunity for saving energy, since many resources (i.e., routers and links) are powered on without being fully utilized. In this context, resource consolidation is a known paradigm for the reduction of the power consumption. It consists in having a carefully selected subset of network devices entering a low power state, and use the rest to transport the required amountof traffic.PARIS-Télécom ParisTech (751132302) / SudocSudocFranceF

    Secure-Rpl: Approach To Prevent Resource-Based Attacks In Wireless Sensor Networks Using Balanced Clustering

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    Internet of Things (IoT) is an evolving computing technology that enables an interconnection amongst physical devices, which offers many advantages, such as easy access to information, cost effectiveness, automation, efficient resource utilisation, reduced human effort and high productivity, all of which have attracted many industry players and researchers. However, the involvement of a vast number of devices and IoT users introduces many issues, including those related to quality of service and security. In IoT, routing amongst resource-constrained devices and nodes is realised by using the routing protocol for a low-power and lossy network (RPL), which selects an optimal route according to the specific objective function

    Rate-Diversity and Resource-Aware Broadcast and Multicast in Multi-rate Wireless Mesh Networks

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    Australian Research Council Discovery Projec
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