40 research outputs found
Distributed Hybrid Simulation of the Internet of Things and Smart Territories
This paper deals with the use of hybrid simulation to build and compose
heterogeneous simulation scenarios that can be proficiently exploited to model
and represent the Internet of Things (IoT). Hybrid simulation is a methodology
that combines multiple modalities of modeling/simulation. Complex scenarios are
decomposed into simpler ones, each one being simulated through a specific
simulation strategy. All these simulation building blocks are then synchronized
and coordinated. This simulation methodology is an ideal one to represent IoT
setups, which are usually very demanding, due to the heterogeneity of possible
scenarios arising from the massive deployment of an enormous amount of sensors
and devices. We present a use case concerned with the distributed simulation of
smart territories, a novel view of decentralized geographical spaces that,
thanks to the use of IoT, builds ICT services to manage resources in a way that
is sustainable and not harmful to the environment. Three different simulation
models are combined together, namely, an adaptive agent-based parallel and
distributed simulator, an OMNeT++ based discrete event simulator and a
script-language simulator based on MATLAB. Results from a performance analysis
confirm the viability of using hybrid simulation to model complex IoT
scenarios.Comment: arXiv admin note: substantial text overlap with arXiv:1605.0487
Routing in multi-hop Ad Hoc networks: an Experimental Approach
In this thesis we investigate the efficiency of routing protocols for Mobile Ad Hoc networks (MANETs) by adopting an experimental approach. MANET routing protocols have been mainly evaluated through simulations which often introduce simplifying assumptions (e.g., radio propagation model) and mask important real characteristics. To avoid these modeling approximations, it is necessary to complement simulation with experiments on real MANETs. This work provides a contribution in this direction reporting our experiences learned by these real measurements. By setting up MANET prototypes, firstly we investigate IEEE 802.11 behavior in singleÂhop MANETs, secondly we focus on an innovative analysis of routing protocols in multiÂhop MANETs by varying scenarios. To the best of our knowledge, our mediumÂscale scenario composed of 23 nodes represents one of the largest MANET testbed. Our experimental results highlight that, in contrast with MANET community, by using proactive routing protocols the overall system gains in scalability, performance and efficiency. These results encourage us identifying in this last class Hazy Sighted Link State (HSLS) as a more suitable protocol. A further contribution of this thesis is hence to design, develop and test an enhanced version of HSLS, strengthened with a mechanism to guarantee the reliability of LSU packets without additional control overhead, and a module to support middleware-network interactions as proposed by the MobileMAN project (EUIST-FP5-FET-Open-IST-2001-38113)
Design of implicit routing protocols for large scale mobile wireless sensor networks
Strathclyde theses - ask staff. Thesis no. : T13189Most developments in wireless sensor networks (WSNs) routing protocols address static network scenarios. Schemes developed to manage mobility in other mobile networking implementations do not translate effectively to WSNs as the system design parameters are markedly different. Thus this research focuses on the issues of mobility and scalability in order to enable the full potential of WSNs to self-organise and co-operate and in so doing, meet the requirements of a rich mix of applications. In the goal of designing efficient, reliable routing protocols for large scale mobile WSN applications, this work lays the foundation by firstly presenting a strong case supported by extensive simulations, for the use of implicit connections. Then two novel implicit routing protocols - Virtual Grid Paging (VGP) and Virtual Zone Registration and Paging (VZRP) - that treat packet routing from node mobility and network scalability viewpoints are designed and analysed. Implicit routing exploits the connection availability and diversity in the underlying network to provide benefits such as fault tolerance, overhead control and improvement in QoS (Quality of Service) such as delay. Analysis and simulation results show that the proposed protocols guarantee significant improvement, delivering a more reliable, more efficient and better network performance compared with alternatives.Most developments in wireless sensor networks (WSNs) routing protocols address static network scenarios. Schemes developed to manage mobility in other mobile networking implementations do not translate effectively to WSNs as the system design parameters are markedly different. Thus this research focuses on the issues of mobility and scalability in order to enable the full potential of WSNs to self-organise and co-operate and in so doing, meet the requirements of a rich mix of applications. In the goal of designing efficient, reliable routing protocols for large scale mobile WSN applications, this work lays the foundation by firstly presenting a strong case supported by extensive simulations, for the use of implicit connections. Then two novel implicit routing protocols - Virtual Grid Paging (VGP) and Virtual Zone Registration and Paging (VZRP) - that treat packet routing from node mobility and network scalability viewpoints are designed and analysed. Implicit routing exploits the connection availability and diversity in the underlying network to provide benefits such as fault tolerance, overhead control and improvement in QoS (Quality of Service) such as delay. Analysis and simulation results show that the proposed protocols guarantee significant improvement, delivering a more reliable, more efficient and better network performance compared with alternatives
Optimized acquisition of spatially distributed phenomena in public sensing systems
Nowadays, an increasing number of popular consumer electronics is shipped with a variety of sensors. The usage of these as a wireless sensing platform, where users are the key architectural component, and ubiquitous access to communication infrastructure has established a new application area called public sensing. We present an opportunistic public sensing system that allows for a flexible and efficient acquisition of sensor readings. This work considers the usage of smartphones as a sensor network in a model-driven sensor data acquisition. We focus on efficiency of query dissemination to mobile nodes, while retaining high effectiveness regarding defined sensing quality of collected data. We adopted and extended an existing geographic routing protocol to design an efficient com- munication system that executes model-driven data acquisition and is robust to changing sensors availability. We use in-network processing paradigm to efficiently distribute queries to mobile nodes and to collect results afterwards. The developed approach was simulated using OMNeT++ network simulator. To verify implemented algorithms and test the overall system performance, we run simulations in different scenarios and evaluate them using adequate cov- erage metrics. Moreover, we verify our intuitive extension to adopted routing protocol and show that it can have a strong impact on the efficiency of protocol in question
5G and beyond networks
This chapter investigates the Network Layer aspects that will characterize the merger of the cellular paradigm and the IoT architectures, in the context of the evolution towards 5G-and-beyond, including some promising emerging services as Unmanned Aerial Vehicles or Base Stations, and V2X communications
Contributions to Vehicular Communications Systems and Schemes
La dernière décennie a marqué une grande hausse des applications véhiculaires comme une nouvelle source de revenus et un facteur de distinction dans l'industrie des véhicules. Ces applications véhiculaires sont classées en deux groupes : les applications de sécurité et les
applications d'info divertissement. Le premier groupe inclue le changement intelligent de voie, l'avertissement de dangers de routes et la prévention coopérative de collision qui comprend la vidéo sur demande (VoD), la diffusion en direct, la diffusion de météo et de nouvelles et les jeux
interactifs. Cependant, Il est à noter que d'une part, les applications véhiculaires d'info divertissement nécessitent une bande passante élevée et une latence relativement faible ; D'autre part, les applications de sécurité requièrent exigent un délai de bout en bout très bas et un canal de
communication fiable pour la livraison des messages d'urgence. Pour satisfaire le besoin en applications efficaces, les fabricants de véhicules ainsi que la
communauté académique ont introduit plusieurs applications à l’intérieur de véhicule et entre véhicule et véhicule (V2V). Sauf que, l'infrastructure du réseau sans fil n'a pas été conçue pour gérer les applications de véhicules, en raison de la haute mobilité des véhicules, de l'imprévisibilité
du comportement des conducteurs et des modèles de trafic dynamiques. La relève est l'un des principaux défis des réseaux de véhicules, car la haute mobilité exige au
réseau sans fil de faire la relève en un très court temps. De plus, l'imprévisibilité du comportement du conducteur cause l'échec des protocoles proactifs traditionnels de relève, car la prédiction du prochain routeur peut changer en fonction de la décision du conducteur. Aussi, le réseau de véhicules peut subir une mauvaise qualité de service dans les régions de relève en raison d'obstacles naturels, de véhicules de grande taille ou de mauvaises conditions météorologiques. Cette thèse se concentre sur la relève dans l'environnement des véhicules et son effet sur les
applications véhiculaires. Nous proposons des solutions pratiques pour les réseaux actuellement déployés, principalement les réseaux LTE, l'infrastructure véhicule à véhicule (V2V) ainsi que les outils efficaces d’émulateurs de relèves dans les réseaux véhiculaires.----------ABSTRACT: The last decade marked the rise of vehicular applications as a new source of revenue and a key differentiator in the vehicular industry. Vehicular Applications are classified into safety and infotainment applications. The former include smart lane change, road hazard warning, and
cooperative collision avoidance; however, the latter include Video on Demand (VoD), live streaming, weather and news broadcast, and interactive games. On one hand, infotainment
vehicular applications require high bandwidth and relatively low latency; on the other hand, safety applications requires a very low end to end delay and a reliable communication channel to deliver emergency messages. To satisfy the thirst for practical applications, vehicle manufacturers along with research institutes introduced several in-vehicle and Vehicle to Vehicle (V2V) applications. However, the wireless
network infrastructure was not designed to handle vehicular applications, due to the high mobility of vehicles, unpredictability of drivers’ behavior, and dynamic traffic patterns. Handoff is one of the main challenges of vehicular networks since the high mobility puts pressure on the wireless network to finish the handoff within a short period. Moreover, the unpredictability of driver behavior causes the traditional proactive handoff protocols to fail, since the prediction of the next router may change based on the driver’s decision. Moreover, the vehicular network may
suffer from bad Quality of Service (QoS) in the regions of handoff due to natural obstacles, large vehicles, or weather conditions. This thesis focuses on the handoff on the vehicular environment and its effect on the vehicular
applications. We consider practical solutions for the currently deployed networks mainly Long Term Evolution (LTE) networks, the Vehicle to Vehicle (V2V) infrastructure, and the tools that can be used effectively to emulate handoff on the vehicular networks
Formal Modeling and Analysis of Mobile Ad hoc Networks
Fokkink, W.J. [Promotor]Luttik, S.P. [Copromotor