Rozprawy doktorskie na temat „Service véhiculaire”
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Naddeh, Nathalie. "Impact of slicing on radio resource management in 5G for vehicular URLLC and eMBB". Electronic Thesis or Diss., Institut polytechnique de Paris, 2022. http://www.theses.fr/2022IPPAS021.
Pełny tekst źródłaThe Fifth Generation-New Radio (5G-NR) introduced the concept of slicing to target different types of services. We consider in this thesis vehicular traffic, with vehicles sending two types of flows: enhanced Mobile BroadBand (eMBB) and Ultra-Reliable and Low Latency Communications (URLLC). These flows are transported in two different slices, the former trying to guarantee and/or maximize the throughput, while the latter has to meet stringent Quality of Service (QoS) constraints in terms of delay, on the order of 1ms, and reliability, on the order of 99,999%. These slices with heterogeneous traffic profiles and QoS requirements must share the same physical infrastructure. This thesis aims to propose new resource allocation schemes to satisfy URLLC stringent QoS requirements without impacting too much eMBB traffic. One main challenge is when resources initially reserved for eMBB must be allocated to the arrival of new URLLC flow. Due to using different numerologies, these resources need to be reconfigured, adding extra delay on the order of 80ms, which exceeds the URLLC delay budget. To respond to this delay problem, we propose proactive resource reservation schemes for URLLC which anticipates the vehicles' arrival in a cell and (re-)configures the slice before their effective arrival in the cell. These approaches enable to meet the delay and throughput requirements of vehicular URLLC and eMBB traffic, respectively.We additionally introduce an inter-slice dimensioning model that considers user's radio conditions and trajectories in the network, which enables taking into consideration users Modulation and Coding Schemes (MCS). By doing so, we achieve a better resource allocation through finer optimization. Our results show that we are able to satisfy traffic requirements with a better resource utilization.Eventually, we investigate an alternative dimensioning model based on large deviation bounds. We analyze the tail of the system corresponding to the URLLC outage region. We consider two approaches: with and without packet queuing. We observe that large deviation bounds result in slightly more over-reservation than the aforementioned approach when applied to URLLC, with the advantage of instantaneous computation of the needed resources
Miao, Lusheng. "Ordonnancement et qualité de service dans les réseaux sans fil véhiculaires". Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1163/document.
Pełny tekst źródłaVehicular ad-hoc Networks (VANETs) are becoming more and more popular as a means to increase the traffic safety and comfort. VANETs have some characteristics due to the vehicle's high speeds mobility such as rapid changes of topology, potentially large-scale, veritable network density and so on. These characteristics have important implications for design of MAC protocol in VANETs. 802.11p standard are attracting increasingly more attention as an important part of the WAVE protocol in VANETs. However the QoS of 802.11p standard can not yet meet the requirements of the realistic vehicular communication networks. Three sub-problems are identified in this study: (i) CCH and SCHs duty cycle problem, (ii) QoS analysis problem and (iii) Multichannel MAC protocol designing problem. Based on these problems, three approaches are proposed in this study: (i) To propose a duty cycle adaptive MAC protocol in which the duty cycle of CCH and SCH will be adapted based on the realtime network traffic; (ii) To propose a model to analyze the QoS in VANETs with various SCH interval settings; (iii) To propose a scheduling and QoS enhancement multi-channel MAC protocol in VANETs. All the proposed algorithms are implemented and validated in discrete event simulator. The simulation results demonstrate that the important QoS metrics such as the reliability, throughput, successful throughput, network capacity and channel utilization are improved by the proposed algorithms in this project
Coronado, Etienne S. "Une architecture de services sur demande pour les communications sans fils véhiculaire". Thèse, Université de Sherbrooke, 2010. http://savoirs.usherbrooke.ca/handle/11143/1945.
Pełny tekst źródłaKhoder, Rami. "Etude de la mobilité et de la qualité de service des communications véhiculaires optiques". Electronic Thesis or Diss., université Paris-Saclay, 2021. http://www.theses.fr/2021UPASG045.
Pełny tekst źródłaThe thesis topic is a part of the global interest in wireless vehicular networks. Over the past decade, the number of road accidents has increased quickly with the growth of the automotive sector. Statistics have demonstrated that the high number of accidents on the road is primarily due to the high traffic density and the lack of information about other drivers' decisions. Recent studies have shown the importance of vehicular communications, which allow the exchange of real-time traffic safety information between vehicles and thus contribute to accidents avoidance.Through vehicular communication, known as vehicle-to-everything (V2X), which includes vehicle-to-vehicle (V2V) and vehicle-to-infrastructure, vehicles can exchange road safety and traffic management messages with low latency. Platoon formation is considered an interactive option that can improve V2X communication and ensure more safety. The vehicle platoon is defined as a group of vehicles following each other, moving in a straight line with a very short inter-vehicle space. Several vehicle platoon formation strategies have been defined in order to manage the platoon's lifetime and stability. However, none of these strategies has taken into account traffic congestion and speed constraints.The first objective of our work is to propose a new platoon formation algorithm called speed platoon splitting (SPS) where vehicles are grouped according to their destination (the leading vehicle has the farthest destination and the latest vehicle has the nearest destination). The main purpose of SPS is to target alleviating congestion by using a ticket pool and classify platoons according to their velocity in two different lanes. Performance analysis shows that SPS provides platoon stability and reduces highway congestion.V2X communications can be achieved via radio frequency (RF) technologies, especially the 802.11p standard. However, due to the accelerated growth in the number of devices, this technology suffers from several problems such as high latency and channel congestion. An alternative communication solution is provided by visible light communication (VLC). VLC is the usage of visible light as a wireless data transmission technique. VLC reduces complexity and cost, enables high precision positioning and increases network scalability and security.The second objective of this thesis tackles the performance of VLC in V2V among the platoon members. For this purpose, we considered two mathematical models validated by simulations for two different scenarios (we have taken an M/M/1 and an M/GI/1 queues for the first and the second scenarios respectively). The performance evaluations present a detailed study of the VLC in the presence of disruptive vehicles and they are used to derive computations of the Quality of Service parameters. The main conclusion drawn is that VLC technology is considered an efficient technique but it is affected by disruptive vehicles.The third objective of the thesis focuses on proposing a mechanism for vertical handover (VHO) between VLC and RF technologies. This objective is composed of two parts, the first one is based on the threshold value to make a vertical handover decision or by using machine learning techniques. The second part is to choose the appropriate technology after VHO using the utility function or the cooperative game.Throughout the thesis, the performance evaluation of the VLC is based on mathematical modelling. Moreover, the simulation is performed to validate this mathematical modelling
Mariyasagayam, Nestor. "Communication Véhiculaires par géolocalisation pour Systèmes de Transports Intelligents". Phd thesis, Ecole Polytechnique X, 2011. http://tel.archives-ouvertes.fr/tel-00613174.
Pełny tekst źródłaBrahmi, Nadia. "Contributions dans les réseaux véhiculaires : routage géographique et localisation". Rouen, 2011. http://www.theses.fr/2011ROUES017.
Pełny tekst źródłaDriven by the transportation safety and efficiency issues, Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) communications are attracting considerable attention in providing Intelligent Transportation Systems (ITS). In this context, a variety of services are offered to road users for improving their security and comfort. These emerging applications include among others safety applications for traffic monitoring and collision prevention, road information services, and infotainment and so on. However, unlike other ad hoc networks, Vehicular ad hoc Networks (VANETs) have their unique characteristics which give rise to many challenging issues. One of the most salient features is the high mobility of vehicles resulting in dynamic topology changes which make data routing remains a key networking issue. In this thesis, we focus on routing problems and propose new protocols that meet the requirements of the emerging vehicular applications. First, we exploit additional information about vehicle’s movement in order to adapt traditional position-based approach for these dynamic environments. We define a new strategy to improve forwarding decisions with an optimal next hop based on a computed metric combining position, velocity and direction information. In the second part of this work, we propose a new class of geographic routing protocols mainly for urban environments. The proposed approaches exploit information about road connectivity and vehicles distribution to find stable routes and reduce the probability of links breakage. The advocated techniques are evaluated by network simulations performed for different vehicular traffic scenarios. Finally, in order to help the deployment of the geographic routing solutions, we propose in the second part of this work a distributed hierarchical location service called Density aware Map-Based Location Service (DMBLS) for Vehicular Ad-hoc Networks. DMBLS makes use of the street digital maps and the traffic density information to define a three level-hierarchy of locations servers that help a source node to discover the location of destination node before sending the data. This infrastructure-less scheme has proven to be robust to node mobility and well suited to dynamic networks
Toufga, Soufian. "Vers des réseaux véhiculaires (VANET) programmables grâce à la technologie SDN (software defined network)". Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30128.
Pełny tekst źródłaThe vehicular network concept, which initially focused on vehicle-to-vehicle communication, is opening up to other types of communications involving vehicles and infrastructure (network), cloud or pedestrians, etc. to meet the needs of the wide variety of new applications envisaged in the framework of the Intelligent Transportation System (ITS). The multitude of network access technologies, the very high mobility of vehicles and their high density in urban areas, and the predominance of wireless communications make it a heterogeneous network, with very dynamic characteristics, some of which are difficult to predict, and subject to scalability problems. Given these issues, one direction, considered by the scientific community, is to apply the SDN (Software Defined Network) paradigm to vehicular networks as a means of, on the one hand, enabling the hybridization and unification of control of different network access technologies and, on the other hand, taking advantage of the centralized view of the network and contextual data from the cloud to develop new control algorithms that can potentially rely on the prediction/estimation of the network state and thus anticipate certain control decisions. Therefore, this thesis is part of this framework. Its contributions aim at developing the concept of SDVN (Software Defined Vehicular Network). Four contributions are developed. The first one specifies the architecture of a hybrid SDN vehicular network capable of meeting the challenges described above. This architecture is complemented by an SDN controller placement solution. We propose a dynamic approach capable of adjusting the optimal placement of controllers according to network topology changes due to road traffic fluctuations. This work also covers the problem of global network vision that an SDN controller can build up, which is a prerequisite and the cornerstone of any network control function. To this problem, we propose amendments and extensions to the "de facto" topology discovery service designed for wired networks to adapt it to the vehicular context. As a complement to the discovery service, we also propose a topology estimation service based on Machine Learning techniques to provide network control functions with a potential vision of the future state of the network and thus open them to proactive and intelligent network control
Mezghani, Farouk. "La dissémination de contenus dans les réseaux véhiculaires". Phd thesis, Toulouse, INPT, 2015. http://oatao.univ-toulouse.fr/14471/1/Mezghani_Farouk_INPT.pdf.
Pełny tekst źródłaMejri, Mohamed Nidhal. "Securing Vehicular Networks Against Denial of Service Attacks". Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCD038/document.
Pełny tekst źródłaIn this thesis we interested in securing Vehicular Ad hoc Networks (VANETs) against Denial of Service attacks (DoS) judged to be the most dangerous attacks to such networks. Our work can be divided into three main parts. First, we studied all the various possible existing vulnerabilities to which are exposed VANETs, we focused especially on denial of service attacks. Based on our expertise in cryptography, we explored, identified and classified the possible solutions to a wide range of VANET security breaches from a cryptographic point of view. Indeed, we showed that cryptography with its primitives and fairly powerful tools solves many VANET security problems. Our first contribution in this direction is a secure group key generation algorithm for VANET platoons. In our second contribution, we have developed two new techniques to detect denial of service attacks in VANET networks mainly characterized by the high mobility and frequent disconnections which considerably complicate the detection. Our first detection algorithm is based on the linear regression mathematical concept, fuzzy logic and three newly defined VANET appropriate metrics. In our second algorithm we define a new Shannon Entropy based metric that we introduced for the first time to detect DoS attacks in VANET. Our third contribution was devoted to the reaction against the detected attacks. For that, we used the techniques offered by game theory. We have proposed two non-cooperative reaction games in strategic and extensive forms. For both detection and reaction proposed schemes, experiments were made essentially for the greedy behavior and jamming attacks. All our proposed algorithms present the advantage of rapidity, to be executed by any node of the network and do not require any modification of the 802.11p MAC layer protocol used as a standard for VANETs. In this work, we have participated in securing VANETs, however we believe that much remains to be done. Namely, for example the study of cryptographic solutions we have conducted, allowed us to discover how the use of cryptography for VANET security is a fairly broad topic which needs to be better explored. This will be for us a very promising subject
Bouchemal, Naila. "Quality of Service Provisioning and Performance Analysis in Vehicular Network". Thesis, Versailles-St Quentin en Yvelines, 2015. http://www.theses.fr/2015VERS029V/document.
Pełny tekst źródłaRoad traffic crashes are one of the world's largest public health and injury problems. Therefore road security has always been the main concern of transportation security stakeholders. During the last decades, public authorities and automotive companies have been involved in the safety improvement of our transportation systems by reducing the consequences of imminent accidents and decreasing the number of road injuries. Nevertheless, most of these preventive measures can only provide passive safety since they focus on the post collision phase. In fact, materials of energy absorption like airbags reduce the impact of an accident but do not prevent it. This recognition of the inadequacy of these passive measures has oriented industrials to new and innovative perspectives that seek to avoid accidents and detect dangers in advance rather than minimize the damage. In fact, according to relevant studies, 60pers of accidents can be avoided if the driver had been alerted half a second before the collision. Drastic steps are already taken by automobile manufacturers to offer to drivers a larger telematics horizon and therefore enhance their range of awareness. If a collision is inevitable, active safety technology can proactively prepare the vehicle for the impact to reduce injuries. For example, vehicles' sensors are employed to measure and assess a vehicle' s condition and environment, enabling the issuance of early warnings to drivers. On the other hand, a remarkable and similar step in that direction is achieved by networking research community using vehicular networks within Intelligent Transportation Systems (ITS)
Lin, Trista Shuenying. "Smart parking : Network, infrastructure and urban service". Thesis, Lyon, INSA, 2015. http://www.theses.fr/2015ISAL0138/document.
Pełny tekst źródłaSmart parking, allowing drivers to access parking information through their smart-phone, is proposed to ease drivers' pain. We first spotlight the manner to collect parking information by introducing the multi-hop sensor network architecture, and how the network is formed. We then introduce the traffic intensity models by looking at the vehicle's arrival and departure probabilities, following the heavy-tailed distribution. We study the deployment strategy of wireless on-street parking sensor layouts. We define a multiple-objective problem and solve it with two real street parking maps. In turn, we present a Publish-Subscribe service system to provide good parking information to drivers. We illustrate the system with a vehicular network and point out the importance of content and context of a driver’s message. To evaluate the resilience, we propose an extended Publish-Subscribe model, and evaluate it under different unforeseen circumstances. Our work is based on the premise that large-scale parking sensors are deployed in the city. We look at the whole picture of urban service from viewpoint of the municipality. As such, we shed light on two main topics: the information collection on sensor deployment and an extended version of Publish-Subscribe messaging paradigm. Our work gives a guideline from network-related perspectives for city before launching a smart parking or any similar real-time urban service. It also provides a meaningful evaluation platform for testing more realistic datasets, such as real vehicle traces or network traffic
Toukabri, Thouraya. "CVS : a framework architecture for D2D-based cellular vehicular services in 4G networks and beyond". Thesis, Evry, Institut national des télécommunications, 2016. http://www.theses.fr/2016TELE0004/document.
Pełny tekst źródłaThe traffic explosion in today’s mobile networks is one of the major concerns of mobile operators. This explosion is mostly widening the gap between networks’ capacities and users’ growing needs in terms of bandwidth and QoS (Quality of Service), which directly impacts operators’ business profitability. In this context, Device-to-Device (D2D) communications offer mobile operators business and technical opportunities by allowing the network traffic offload with D2D direct communications between mobile devices. The recent standardization of D2D-based services as Proximity Services (ProSe) by the 3GPP provides already a set of enhancements to the current LTE/4G architecture to support these services. However, still in its infancy, the proposed solutions are envisioned for short-term market deployments and for a limited set of service categories (i.e public safety services). As a first contribution of this thesis, the proposed Distributed ProSe Architecture enhances the current ProSe architecture for a longer term deployment perspective of D2D-based services. On the basis of this enhanced architecture, vehicular communications and related services are further investigated as a specific implementation of ProSe as well as a new market opportunity for mobile operators. The CVS (Cellular Vehicular Services) solution is then introduced as an architecture framework that enables the integration of vehicular networks into mobile operators’ network infrastructure. A mobile network clustering algorithm and D2D relay-based communication mechanisms are used in the solution design in order to optimize the use of both core and radio network resources. Performance evaluation through analytical modeling and simulations are also carried out to validate the proposed contributions
Toukabri, Thouraya. "CVS : a framework architecture for D2D-based cellular vehicular services in 4G networks and beyond". Electronic Thesis or Diss., Evry, Institut national des télécommunications, 2016. http://www.theses.fr/2016TELE0004.
Pełny tekst źródłaThe traffic explosion in today’s mobile networks is one of the major concerns of mobile operators. This explosion is mostly widening the gap between networks’ capacities and users’ growing needs in terms of bandwidth and QoS (Quality of Service), which directly impacts operators’ business profitability. In this context, Device-to-Device (D2D) communications offer mobile operators business and technical opportunities by allowing the network traffic offload with D2D direct communications between mobile devices. The recent standardization of D2D-based services as Proximity Services (ProSe) by the 3GPP provides already a set of enhancements to the current LTE/4G architecture to support these services. However, still in its infancy, the proposed solutions are envisioned for short-term market deployments and for a limited set of service categories (i.e public safety services). As a first contribution of this thesis, the proposed Distributed ProSe Architecture enhances the current ProSe architecture for a longer term deployment perspective of D2D-based services. On the basis of this enhanced architecture, vehicular communications and related services are further investigated as a specific implementation of ProSe as well as a new market opportunity for mobile operators. The CVS (Cellular Vehicular Services) solution is then introduced as an architecture framework that enables the integration of vehicular networks into mobile operators’ network infrastructure. A mobile network clustering algorithm and D2D relay-based communication mechanisms are used in the solution design in order to optimize the use of both core and radio network resources. Performance evaluation through analytical modeling and simulations are also carried out to validate the proposed contributions
Mouawad, Nadia. "SDN based Mobility Management and Quality of Service Provisioning for 5G Vehicular Networks". Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASV003.
Pełny tekst źródłaVehicle to everything (V2X), including vehicle-to-vehicle (V2V) and vehicle-to-infrastructure(V2I), is the umbrella for the vehicular communication system, where active road safety, infotainment and traffic management messages are transmitted over high-bandwidth, low-latency, high-reliability links, paving the way to fully autonomous driving. The ultimate objective of next generation V2X communication systems is enabling accident-free cooperative driving that uses the available roadway efficiently. To achieve this goal, the communication system will need to enable a diverse set of use cases, each with a specific set of requirements.The main use case categories requirements analysis, specifically the critical realtime applications, points out the need for an efficient V2X system design that could fulfill the network performance. The Fifth Generation (5G) technology, with its provisioned QoS features in terms of high capacity and low latency, is advocated as a prominent solution to cope with the firm requirements imposed by V2X applications.In this multifaceted vehicular 5G ecosystem, diverse communication technologies are envisioned, spanning from IEEE 802.11p, LTE, LTE-V to vehicular visible light communications. Therefore, the heterogeneity of radio access technologies will raise a concern regarding the seamless mobility management and the quality of service guarantee.This thesis provides a novel mobility management scheme devised for 5G vehicular networks based on the emerging Software Defined Networking (SDN) technology.SDN provides network programmability that strives to achieve an efficient network resource allocation and mobility management.Our research work tackles three objectives. At a first stage, we design a software defined vehicular network topology. On the top of this topology, we implement twoSDN applications, namely Network Selection Application and Mobility Management Application. The proposed architecture is enhanced by a controller placement solution that aims at reducing communication latency. Moreover, a special concern is devoted to design a SDN road active safety application that controls speed traps placement. The proposed application aims at reducing accidents rate which is a main purpose of future Intelligent Transportation System.The second objective of this thesis tackles the mobility management problem. This is achieved by implementing SDN mobility related applications on the top of the adopted network topology. The first application is dedicated to solve the network selection problem; it aims at mapping running V2X sessions to the corresponding technology. The second application is conceived to solve the handover procedure; this is achieved using packets duplication and introducing an efficient routing algorithm.The third thesis objective is focused on QoS provisioning for V2X communications
Soua, Ahmed. "Vehicular ad hoc networks : dissemination, data collection and routing : models and algorithms". Electronic Thesis or Diss., Evry, Institut national des télécommunications, 2013. http://www.theses.fr/2013TELE0028.
Pełny tekst źródłaEach day, Humanity loses thousands of persons on roads when they were traveling to work, to study or even to distract. The financial cost of these injuries is also terrifying: Some statistics evaluate the financial cost of vehicle accidents at 160 billion Euro in Europe each year. These alarming figures have driven researchers, automotive companies and public governments to improve the safety of our transportation systems and communication technologies aiming at offering safer roads and smooth driving to human beings. In this context, Vehicular Adhoc Networks, where vehicles are able to communicate with each others and with existent road side units, emerge as a promising wireless technology able to enhance the vision of drivers and offer larger telematic horizon. VANETs promising applications are not only restricted to road safety but span from vehicle trafficoptimization like flow congestion control to commercial applications like file sharing and internet access. Safety applications require that their alert information is propagated to the concerned vehicles (located in the hazardous zone) with little delay and high reliability. For these reasons, this category of applications is considered as delay sensitive and broadcast-oriented nature. While classical blind flooding is rapid, its major drawback is its huge bandwidth utilization. In this thesis, we are interested on enhancing vehicular communications under different scenarios and optimizations: First, We focus on deriving a new solution (EBDR) to disseminate alert messages among moving vehicles while maintaining it efficient and rapid. Our proposal is based on directional antennas to broadcast messages and a route guidance algorithm to choose the best path for the packets. Findings confirmed the efficiency of our approach in terms of probability of success and end-to-end delays. Moreover, in spite of the broadcast nature of the proposed technique, all transmissions stop very soon after the arrival of a packet to its destination representing a strong feature in the conception of EBDR. Second, we propose a novel mathematical framework to evaluate the performance of EBDR analytically. Although most of the proposed techniques present in literature use experimental or simulation tools to defend their performance, we rely here on mathematical models to confirm our achieved results. Our proposed framework allows to derive meaningful performance metrics including the probability of transmission success and the required number of hops to reach thefinal destination. Third, we refine our proposed broadcast-based routing EBDR to provide more efficient broadcasting by adjusting the transmission range of each vehicle based on its distance to the destination and the local node density. This mechanism allows better minimization of interferences and bandwidth's saving. Furthermore, an analytical model is derived to calculate thetransmission area in the case of a simplified node distribution. Finally, we are interested on data collection mechanisms as they make inter-vehicle communications more efficient and reliable and minimize the bandwidth utilization. Our technique uses Q-learning to collect data among moving vehicles in VANETs. The aim behind using the learning technique is to make the collecting operation more reactive to nodes mobility and topology changes. For the simulation part, we compare it to a non-learning version to study the effect of the learning technique. Findings show that our technique far outperforms other propositions and achieves a good trade off between delay and collection ratio. In conclusion, we believe that the different contributions presented in this Thesis will improve the efficiency of inter-vehicle communications in both dissemination and data collection directions. In addition, our mathematical contributions will enrich the literature in terms of constructing suitable models to evaluate broadcasting techniques in urban zones
Soua, Ahmed. "Vehicular ad hoc networks : dissemination, data collection and routing : models and algorithms". Phd thesis, Institut National des Télécommunications, 2013. http://tel.archives-ouvertes.fr/tel-00919774.
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