Véhicule-à-tous (V2X) se réfère à un Système de Transport Intelligent (ITS) où les véhicules et l'infrastructure sont interconnectés. Cette connectivité permet une connaissance précise des conditions de circulation sur l'ensemble du réseau routier, ce qui contribue à améliorer la sécurité routière, réduire les temps d'encombrement et éviter les pertes économiques. Cette communication permet aussi une variété de nouvelles applications pour la sécurité routière et l'infodivertissement. Bien que la communauté de scientifique ait réalisé de grands progrès dans l'étude sur le V2X, il reste encore des défis à surmonter et des problèmes clés qui doivent être étudiés plus en profondeur. Cette thèse considère deux des questions les plus importantes; fiabilité et sécurité des communications V2X. Du point de vue de la fiabilité, nous proposons d'abord une méthode basée sur la modélisation de l'utilisateur pour évaluer la capacité de la norme DSRC IEEE 802.11p à répondre aux exigences de Qualité De Service (QoS) de la diffusion des messages de sécurité. La nouveauté de la méthode réside dans son application qui élimine le problème de la définition d'un modèle Markovien par la détermination des moments d'équilibre du processus de retard. Cette méthode fournit des informations importantes sur les paramètres de conception IEEE 802.11p et sur ses fonctionnalités, ce qui permet d'améliorer la configuration proposée. De plus, nous proposons un modèle Régénératif pour résoudre le problème de la caractérisation des processus de trafic interconnecté dans les réseaux V2X hybrides à grande échelle. Ce dernier est une préoccupation majeure pour parvenir à une opérabilité efficace et adéquate pour les réseaux de véhicules à grande échelle. Du point de vue de la sécurité, nous introduisons une nouvelle méthodologie d'optimisation. Notre méthodologie lie les exigences de QoS des différentes classes d'application avec le paramètre de conception de base du mécanisme de résolution de contention dans le protocole MAC IEEE 802.11p. En outre, un nouvel algorithme de détection d'attaque de brouillage dans l'environnement véhiculaire est proposé. L'algorithme utilise la méthodologie d'optimisation développée pour définir un seuil de détection et intègre la méthode séquentielle de détection pour détecter les attaques de brouillage à chaque fois que la valeur seuil est franchie. Des expérimentations analytiques et de simulation approfondies ont été effectuées pour chaque contribution afin de montrer la validité des méthodes/modèles proposés et de prouver leur efficacité. / Vehicle-to-anything (V2X) refers to an Intelligent Transportation System (ITS) where the vehicles and infrastructure systems are all interconnected with each other. This connectivity provides precise knowledge of the traffic situations across the entire road network which in turn helps to enhance traffic safety, reduce congestion time, avoid economic losses, in addition to enable a variety of novel ITS applications for road safety and passenger infotainment. V2X communications is based on two technologies; Dedicated Short-Range Communications (DSRC) which is an essential technology for realizing V2X and cellular networks which provide an o_-the-shelf potential solution for V2X communications. Although the research community has achieved much great progress on V2X study, there are still some challenges that need to be overcome and some key issues that need to be further investigated. This thesis considers two of the most prominent issues; reliability and security of V2X communications. From the reliability perspective, we first propose User Model-based Method to evaluate the capacity of IEEE 802.11p-based DSRC standard to meet the Quality-of-Service (QoS) requirements of safety messages dissemination. The novelty of the method lies in its application which avoids the problem of defining a Markovian model by determining the steady state moments of the induced delay process. This applicability feature provides important insights about IEEE 802.11p design parameters and its functionality leading to proposed reconfigurations for enhanced performance. Moreover, we propose Regenerative model, that we believe to be the first to address the problem of interconnected-traffic process characterization in large-scale hybrid V2X networks. The latter is a primary concern in achieving efficient and adequate operability for large-scale vehicular networks. From the security perspective, we introduce a new optimization methodology which ties the QoS requirements of different application classes with the basic design parameters of the contention resolution mechanism in IEEE 802.11p MAC protocol. In addition, a novel detection algorithm for jamming attacks in the vehicular environment is proposed. The algorithm utilizes the developed optimization methodology to de_ne a detection threshold. By integrating the sequential detection of change method it traces and detects jamming attacks whenever the threshold value is crossed. Analytical and simulation experimentations have been performed for each contribution to show the validity of the proposed methods/models and to prove their efficiency.

Cylinder speed variations in a combustion engine is an unwanted phenomenon caused by a number of different reasons. Inaccurate fuel delivery from the individual injectors, resonance frequencies in the drive train and faulty sensor readings are some probable causes. There is a need to investigate the potential of different cylinder balancing controllers in a simulation environment before implementing them in the ECU hardware. The thesis is about developing a simulation framework where different controllers can be tested. The framework will generate an engine speed signal based on injected fuel mass to the individual cylinders. A PI controller that makes individual fuel adjustments to the cylinders is implemented in the framework and tested for three different operating points and three different types of disturbances. The results show that the framework is able to generate an accurate engine speed signal based on the commanded fuel amount. Moreover the controller is able to eliminate imbalances caused by error in injected fuel mass as well as specific type of periodic load disturbances in the drive line. Some disturbances cannot be handled by the PI controller, as they lie outside of its controllable region. The simulation framework shows promising results and while further work is needed in some areas, it can work as a foundation for future development and controller evaluation.

El presente trabajo de investigación se llevó a cabo en la idea de formular propuestas de mejora para la reducción del TCO por atención de la gestión de flotas de una empresa que brinda servicio a las principales empresas de telecomunicaciones. Actualmente, el costo de esta gestión representa el 42% del total de costos de la compañía, por tanto, representa una oportunidad importante para iniciar un análisis de su TCO e identificar potenciales de ahorro. Esta empresa tiene como reto convertirse en el proveedor de servicios de red de referencia para las empresas de comunicaciones y energía de manera rentable, por este motivo una adecuada gestión de sus costos es el camino para ser competitivos. El problema identificado radica en el no cumplimiento de los presupuestos asignados a la gestión de flotas, siendo este presupuesto repartido entre todas sus sedes. El impacto negativo de esta situación radica en sobrecostos para la organización y posibles pérdidas de clientes debido a no poder ofertar precios competitivos en las licitaciones que participa. Para resolver la problemática, el trabajo de investigación se compone de cinco capítulos: El primero se centra en la definición del problema y la justificación de por qué es necesario el análisis de la presente. En el segundo capítulo, se presenta los conceptos relacionados al TCO y gestión de flotas, así como de herramientas lean que serán la base para formular las propuestas tanto para reducción de TCO e incremento de atenciones; adicionalmente el estado del arte con investigaciones académicas relacionadas al tema. En el tercer capítulo, se describe la situación actual de la gestión de flota relacionado al TCO y nivel de atenciones, se analiza y delimita la sede y componentes del costo para mejora, además de identificar las causas que originan los problemas. Con la identificación de las causas, en el cuarto capítulo, se procede a desarrollar la propuesta de mejora apoyada en herramientas Lean, para finalmente terminar con los cálculos de beneficios esperados y principalmente el impacto en el TCO y presupuesto actual de la gestión. Por último, en el capítulo quinto se muestran las conclusiones y recomendaciones finales para la implementación. El trabajo realizado espera como resultado final la reducción en el TCO por atención y el cumplimiento de los presupuestos asignados de la gestión de flotas, optimizando la gestión de costos de la compañía y contribuir de manera positiva incrementando las posibilidades de abrir nuevos negocios ofreciendo precios competitivos en las licitaciones. / This research work was carried out with the idea of ​​formulating improvement proposals for the reduction of the TCO for fleet management by attention of a company that provides service to the main telecommunications companies. Currently, the cost of this management represents 42% of the company's total costs, therefore, it represents an important opportunity to start an analysis of its TCO and identify potential savings. The challenge of this company is to become the reference network service provider for communications and energy companies in a profitable manner, for this reason an adequate management of their costs is the way to be competitive. The problem identified is about the non-compliance with the budgets assigned to fleet management, this budget being distributed among all its offices. The negative impact of this situation generates over costs for the organization and possible loss of customers due to not being able to offer competitive prices in the tenders it participates. To solve the problem, the thesis is divided in five chapters: The first focuses on the definition of the problem and the justification of why the analysis of this thesis is necessary. In the second chapter, the concepts related to TCO and fleet management are presented, as well as lean tools that will be the basis for formulating proposals for both reductions of TCO and increase of attentions; additionally, the state of the art with academic research related to the topic. In the third chapter, the current situation of fleet management related to the TCO and level of attentions are described, the office and the cost components for improvement are analyzed and defined, in addition to identifying the causes that originate the problems. With the identification of the causes, in the fourth chapter, we proceed to develop the improvement proposal supported by Lean tools, to finally finish with the calculations of expected benefits and mainly the impact on the TCO and current management budget. Finally, the fifth chapter shows the final conclusions and recommendations for implementation. The work performed expects as a final result the reduction in the TCO by attention and compliance with the assigned budgets of fleet management, optimizing the company's cost management and contributing positively by increasing the possibilities of opening new businesses by offering competitive prices in tenders. / Trabajo de investigación

The aim of this work is to show the effectiveness of techniques that allow a user to maintain its privacy and anonymity while participating in real word scenario. Users need to communicate with each other in many situations in order to share information. This creates the danger of the user’s privacy being breached and it can discourage users from taking active participation in any information sharing task. There are many real scenarios or application where users want to remain anonymous while having their communication secured. This is so in vehicular communication systems. Group signatures are versatile cryptographic tools that are suitable when we need security and privacy protection. A group signature scheme allows members of a group to sign messages on behalf of the group. Any receiver can verify the message validity but cannot discover the identity of the sender from the signed message or link two or more messages from the same signer. However, the identity of the signer can be discovered by an authority using a signed message. For this reason, Group Signature schemes were proposed in the context of vehicular communication systems. In this context, communication and computation overheads are critical. Thus, the focus of this thesis is to implement and compare different group signature schemes in terms of overhead introduced due to processing cost, and analytically evaluate their suitability for vehicular communication scenarios.

The idea of vehicular communication systems could bring more safety, immunity and assurance in driving while it poses a variety of applications in traffic efficiency, driver assistance, environmental hazards, road conditions and infotainment. The aim is to make driving safer and to facilitate driving to the full extent, even on dangerous roads. However, having effective and robust operations within the VC system needs an infrastructure to handle threats, faults, illegitimate activities and unexpected incidents. Message authentication, integrity, non-repudiation and privacy within such a system are considered as the most controversial issues from security perspective. The idea is to protect privacy not only from legal point of view, but also from technical perspective in terms of using privacy enhancing technologies. To provide security within such a system, the idea of Public Key Infrastructure is considered as a promising solution. Using long-term certificates does reveal the real identity of the owner. Since users’ privacy is considered as the main security requirement in the VC system, standard certificates (X.509) and normal PKI cannot be used within a VC network. There are some functionalities and features for vehicular communication systems that do not exist in standard PKI. As a result, using pseudonym certificates to perform transactions within the VC system is a solution. In this report, a vehicular public key infrastructure, called VPKI, is proposed. OpenCA is used as the PKI, equipped with Pseudonym Certificate Authority (PCA), Long-Term Certificate Authority (LTCA) and Pseudonym Resolution Authority (PRA). These authorities are certified by the RCA and they have privileges to perform their tasks. LTCA is responsible for issuing long-term certificates while PCA is responsible for issuing pseudonym certificates. PRA is the authority to perform pseudonym resolution to identify the real identity of a pseudonym certificate. When it comes to CRL, PCA is the responsible authority to determine revoked pseudonym certificates in order to keep the system secure. Three protocols are then proposed to obtain pseudonym certificates, latest version of pseudonym CRL as well as performing pseudonym resolution. Obtaining pseudonym certificates is done in two phases. Firstly, each vehicle sends a request to LTCA to get a valid token. In the second step, the token is used by PCA to issue pseudonym certificates.

This project has been carried out at the Electronic Embedded Systems Architecture Department at Volvo Construction Equipment (VCE), Eskilstuna, Sweden. It forms the baseline for a stepwise systematic research initiative to convert wired technologies used for certain in-vehicle control and communication components to wireless technologies. In-vehicle wireless networks are being increasingly improvised and researched to minimize the manufacturing and maintenance cost of the total amount of wiring harnesses within the vehicles. Fault tracking and maintenance becomes convenient within a wireless network. Wireless intra-vehicular communication provides an open architecture that can accommodate new components and applications. One such usability has been studied in this thesis for the Display Control Unit of Volvo paver machines. A newly designed hardware demands new technologies to ensure operator safety, security, comfort, convenience, and information. The research conducted in this thesis takes into account five probable use-cases in terms of control and communication around the new hardware, and studies suitable wireless technologies that could replace the wired technology that will be used. From a detailed literature study and the specifications provided by VCE, WAVE/IEEE802.11p and DMG/IEEE 802.11ad have been selected as optimal candidates. These two have been modelled at the physical layer of the system. After comparing the results of WAVE for 4 different channel models and 8 different coding and modulation schemes, it has been found that 1/2BPSK(3 Mbps) and 1/2 QPSK(6 Mbps) are optimal for the 3 Rician Fading Channels of Rural LOS, Urban LOS, and Highway LOS. For use-cases that involve larger distances and a large exchange of control signals, WAVE is a good choice. DMG has 19 modulation schemes for Single Carrier Modes and some of them are extremely robust at low SNR. Around SNR 20, it shows lesser packet errors than WAVE. The lower error rate is also evident from the BER values. For use-cases that involve smaller distances and a lot of image data, DMG is preferable. The work, however, does not study the safety and security aspects. Thean alysis and modelling are theoretical being based on literature studies and the necessary parameters provided by VCE. The model needs to be evaluated against field studies and practical measurements with a prototype before implementation inside the paver.

Dans cette thèse, nous nous intéressons à deux types d’architectures dans les réseaux véhiculaires : les réseaux à infrastructure et les réseaux sans infrastructure. L’objectif de ce travail est de définir des solutions améliorant la connectivité des passagers des véhicules dans des environnements à densité variable en points d’accès. Pour ceci, dans un premier temps, nous nous intéressons aux algorithmes de guidage routier (dont l’objet est de guider un véhicule d’un point de départ vers un point d’arrivée) en prenant en compte les emplacements des points d’accès le long des routes. Notre première contribution est de définir un algorithme de guidage qui offre une connectivité supérieure au chemin par défaut (en général le plus court chemin) tout en maintenant une distance parcourue raisonnable pour les passagers du véhicule. Nous nous intéressons également à la minimisation du nombre de handovers afin d’améliorer la qualité de service du réseau. Nous avons évalué notre algorithme en termes de distance couverte et du nombre de handovers, tout en s’assurant de garder une distance totale parcourue raisonnable. Nous avons étudié dans un deuxième temps l’impact du choix de l’algorithme du guidage routier sur les performances de la couche réseau, où nous avons pris en compte deux types de protocoles de routage de données : réactif et proactif. Ensuite, nous avons étudié une problématique récurrente dans les réseaux véhiculaires qui est le routage des données de véhicule à véhicule. Ceci est particulièrement utile en absence d’une infrastructure disponible sur la route. Nous proposons une solution inter-couches («cross-layer») qui tire profit des caractéristiques des réseaux sans fil pour offrir un protocole de routage multi-sauts. Contrairement à la plupart des propositions de protocoles de routage, notre solution ne requiert pas un échange de messages de signalisation entre les voisins, ce qui améliore les performances du réseau en termes de charge utile et efficacité, surtout pour un réseau à forte mobilité comme c’est le cas pour des réseaux véhiculaires où les voisins changent d’une seconde à une autre, rendant problématique la mise à jour des informations de chaque nœud mobile sur son entourage / In this thesis, we focus on two types of architectures in vehicular networks: infrastructure networks and networks without infrastructure. The goal of this work is to define solutions to improve connectivity for passengers of vehicles in environments with variable density of access points. For this, we start by studying route guidance systems (whose purpose is to guide a vehicle from a starting point to a destination point), taking into account the locations of access points along roads. Our first contribution is to define a route guidance algorithm that offers superior connectivity compared to the default path (usually the shortest path) while maintaining a reasonable distance for passengers. We dealt also another issue which consists in minimizing the number of handovers to improve the quality of network service. We evaluated our algorithm in terms of covered distance and the number of handovers, while making sure to keep a reasonable traveled distance. After that, we studied the impact of the choice of route guidance algorithm in the performance of the network layer, where we took into account two types of routing protocols data: reactive and proactive. Next, we studied a recurrent problem in vehicular networks which is routing data from vehicle to vehicle. This is particularly useful in the absence of available infrastructure on the road. We propose a cross-layer architecture that takes advantage of the characteristics of wireless networks to design a multi-hops routing protocol. Unlike most proposals for routing protocols, our solution does not require an exchange of signaling messages between neighbors, and so improves network performance in terms of overhead and efficiency, especially for networks with high mobility such as vehicular networks, where neighbors change frequently, making it difficult to update information from each mobile node on its surroundings

L'explosion du trafic dans les réseaux mobiles d'aujourd'hui est l'une des préoccupations majeures des opérateurs mobiles. En effet, entre investir dans le développement de l’infrastructure pour supporter l’évolution des besoins des utilisateurs et faire face à la concurrence accrue des nouveaux acteurs du marché, l’enjeu est considérable. Dans ce contexte, les communications Device-to-Device (D2D) offrent aux opérateurs mobiles de nouvelles opportunités aussi bien financières que techniques, à travers les communications directes entre les appareils mobiles permettant de délester le réseau d'une partie du trafic. L'organisme de standardisation 3GPP a défini des évolutions de son architecture LTE/4G fonctionnelle pour supporter les communications D2D dans le cadre de Services de Proximité (ProSe). Cependant, les modèles économiques autour de ces nouveaux services sont encore flous et les solutions actuellement proposées par le 3GPP visent un déploiement à court terme d’un ensemble limité de services (ex : les services de sécurité publique). La première contribution proposée dans le cadre de cette thèse est une évolution de l'architecture ProSe vers une architecture cible distribuée dans laquelle les fonctions liées à ProSe sont mutualisées avec d'autres fonctions réseaux. La deuxième contribution porte sur l’intégration des services véhiculaires dans les réseaux mobiles en tant que services ProSe particuliers reposant sur les communications D2D. L'architecture CVS (Cellular Vehicular Services) est alors proposée comme solution pour un déploiement à grande échelle des services véhiculaires en s'appuyant sur une nouvelle évolution de l’architecture ProSe distribuée. Un algorithme de « clustering » ainsi que des procédures de communication en mode relais D2D sont utilisés dans la conception de la solution afin d’optimiser l'usage des ressources du réseau. Enfin, les performances de ces contributions sont évaluées à l'aide de modèles analytiques et de simulations afin de valider les approches et solutions proposées / The 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

Localization of nodes is an important aspect in a vehicular ad-hoc network (VANET). Research has been done on various localization methods. Some are more apt for a specific purpose than others. To begin with, we give an overview of a vehicular ad-hoc network, localization methods, and how they can be classified. The distance bounding and verifiable trilateration methods are explained further with their corresponding algorithms and steps used for localization. Distance bounding is a range-based distance estimation algorithm. Verifiable trilateration is a popular geometric method of localization. A dedicated automated highway infrastructure can use distance bounding and/or trilateration to localize an automated vehicle on the highway. We describe a highway infrastructure for our analysis and test how well each of the methods performs, according to a security measure defined as spoofing probability. The spoofing probability is, simply put, the probability that a given point on the highway will be successfully spoofed by an attacker that is located at any random position along the highway. Spoofing probability depends on different quantities depending on the method of localization used. We compare the distance bounding and trilateration methods to a novel method using friendly jamming for localization. Friendly jamming works by creating an interference around the region whenever communication takes place between a vehicle and a verifier (belonging to the highway infrastructure, which is involved in the localization process using a given algorithm and localization method). In case of friendly jamming, the spoofing probability depends both on the position and velocity of the attacker and those of the target vehicle (which the attacker aims to spoof). This makes the spoofing probability much less for friendly jamming. On the other hand, the distance bounding and trilateration methods have spoofing probabilities depending only on their position. The results are summarized at the end of the last chapter to give an idea about how the three localization methods, i.e. distance bounding, verifiable trilateration, and friendly jamming, compare against each other for a dedicated automated highway infrastructure. We observe that the spoofing probability of the friendly jamming infrastructure is less than 2% while the spoofing probabilities of distance bounding and trilateration are 25% and 11%, respectively. This means that the friendly jamming method is more secure for the corresponding automated transportation system (ATS) infrastructure than distance bounding and trilateration. However, one drawback of friendly jamming is that it has a high standard deviation because the range of positions that are most vulnerable is high. Even though the spoofing probability is much less, the friendly jamming method is vulnerable to an attack over a large range of distances along the highway. This can be overcome by defining a more robust infrastructure and using the infrastructure's resources judiciously. This can be the future scope of our research. Infrastructures that use the radio resources in a cost effective manner to reduce the vulnerability of the friendly jamming method are a promising choice for the localization of vehicles on an ATS highway.

Is there one or several French languages? What about African French language? The linguistic studies on French in Africa accentuate the uniqueness of the Ivorian popular French. Since Ivorians speak many different languages and as they have no real vehicular language, they appropriated the French which was implanted and imposed at the time of the colonization. Today, we witness the presence of various types of French (acrolectal, mesolectal, basilectal) that people use as a result of the effort to adapt this foreign language to local reality. The main purpose of this study is to classify some of the different characteristic features of the Popular Ivorian French according to previous studies, then to identify those features of Popular Ivorian French in Ahmadou Kourouma’s novel Allah is not obliged. We identified fourteen characteristics which particularize Popular Ivorian French. Most of these characteristics are present in Kourouma’s Allah is not obliged but some are not.  In conclusion, we can see that the Ivoirians have adapted and shapedFrench to create a language they feel at home with. They have added new expressions, neologisms and metaphors in order to better convey their messages and to better understand each others.