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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Efficient Secure Communication in VANETs under the Presence of new Requirements Emerging from Advanced Attacks

Bittl, Sebastian 29 September 2017 (has links)
Drahtlose ad-hoc Netzwerke zwischen Fahrzeugen, sog. Vehicular ad-hoc Networks (VANETs), bilden einen Ansatz zur Verbesserung der Verkehrssicherheit, indem sie zukünftige kooperative Fahrerassistenzsysteme ermöglichen. Diese Netzwerke erfordern ein hohes Sicherheitsniveau, sowohl in Bezug auf Datenintegrität und -authentizität als auch im Bereich Datenschutz. Aktuell verfügbare Technologien können diese Anforderungen nicht vollständig erfüllen. Etliche Nachteile aktueller VANET-Ansätze werden in dieser Arbeit aufgezeigt. In dieser Arbeit werden drei Schachpunkte von ETSI ITS bzw. WAVE basierten VANETs identifiziert, welche Angriffe auf Teilnehmer dieser Netzwerke ermöglichen. Diese ergeben sich aus 1. konstanten und für Teilnehmer charakteristischen Datensätzen innerhalb der zyklisch versandten Statusnachrichten, welche den Datenschutz der Fahrzeuge und damit auch ihrer Fahrer gefährden, 2. die Strategie zur Verteilung von digitalen Zertifikaten von Zertifizierungsstellen erlaubt es selbst Angreifern mit minimalen Fähigkeiten (einzelner, statischer Angreifer von außerhalb des Netzwerkes) die Kanallast in einem großen Teilgebiet des Netzwerkes massiv zu erhöhen, 3. GNSS Manipulation durch sog. spoofing erlaubt Angriffe auf zeit- und ortsbasiere Informationen in Fahrzeugen, wodurch sich folgende Gefährdungen ergeben: a. Der Grundanforderung Teilnehmer durch Nichtabstreitbarkeit der gesendeten Daten für ihr Verhalten zur Rechenschaft ziehen zu können wird die Grundlage entzogen, da der Zeitpunkt des Sendens der Daten nicht mehr sicher festgestellt werden kann. b. Die Zugangskontrolle zum System wird gefährdet, da angegriffene Teilnehmer veraltete Nachrichten und digitale Zertifikate akzeptieren. c. Angreifer können einen sog. Sybil Angriff durchführen. Es ist notwendig die identifizierten Sicherheitsprobleme zu beheben um eine sichere Verwendung von VANETs für zukünftige kooperative Fahrerassistenzsysteme zu ermöglichen. Weiterhin werden einige Designprobleme in ETSI ITS Protokollen identifiziert. Die bisherige Art der Nachrichtenzusammensetzung auf den einzelnen Protokollschichten führt häufig zu Gesamtnachrichten, welche die zulässige maximale Gesamtlänge auf niedrigen Protokollschichten überschreitet. Da solche Nachrichten nicht versandt werden könne, können diverse wichtige Datensätze nicht im Netzwerk verteilt werden. Außerdem ist keine verschlüsselte Ende-zu-Ende Kommunikation über eine Multi-Hop Verbindung möglich, da die notwendigen Routing-Informationen den weiterleitenden Teilnehmern nicht zur Verfügung stehen. Es werden Vorschläge diskutiert, wie diese Probleme gelöst werden können. Zur Adressierung der genannten Probleme werden u.a. folgende Maßnahmen vorgeschlagen: 1. Eine sichere Zeitsynchronisierung in VANETs ist notwendig. 2. Das Speichern von mehreren Fahrzeug-Zertifikaten mit gleicher Laufzeit ist zu vermeiden. 3. Das Speichern von Fahrzeug-Zertifikaten mit zukünftiger Laufzeit ist auf ein Minimum zu begrenzen. 4. Konstante und gleichzeitig für Teilnehmer charakteristische Datensätze sind nicht zu versenden. 5. Weitere Mechanismen zur Minimierung der Kanallast durch Zertifikatsverteilung sind notwendig, u.a. a. nach einem Pseudonymwechsel sollte dieser explizit signalisiert werden um das Versenden aller Zertifikate in der Umgebung durch die Detektion eines neuen Nachbarn zu verhindern. b. es sollte keine Verteilung von Zertifikatsketten erfolgen, da einzelne Zertifikate ausreichen. c. die Anzahl der Übermittlungen von Zertifikaten von Zertifizierungsstellen ist zu minimieren. Die Anwendung der genannten Verbesserungen überwindet die meisten Sicherheitsprobleme (1,2, und 3c). Für die weiteren Probleme kann der notwendige Aufwand für einen erfolgreichen Angriff deutlich erhöht werden. / Vehicular ad-hoc networks (VANETs) are an important approach to increase future safety of driving by enabling cooperative advanced driver assistance systems. However, rigid security and privacy requirements employed to conducted wireless data exchange still pose significant challenges for VANET approaches. Several weaknesses of the current state of the art of VANET approaches from ETSI ITS as well as WAVE standard frameworks have been identified in this work. Three main attack surfaces of ETSI ITS or WAVE based VANETs are identified in this thesis, which are 1. constant and distinctive content in data fields within frequently sent VANET messages highly endanger privacy of vehicles, and thereby also their drivers, 2. the distribution strategy of certificate authority (CA) certificates allows even a simple static outsider attacker to massively increase the channel load within a large area around the attacker, which significantly exceeds his own communication range, and 3. GNSS spoofing modifying time and position information inside nodes a. endangers the basic system requirement of accountability by circumventing the nonrepudiation feature of the employed digital signature scheme, b. endangers the access control system by forcing the acceptance of outdated messages and certificates, and c. enables an attacker to perform a Sybil attack. The identified security problems need to be overcome to re-enable secure usage of VANETs and ADASs, which are based on the information obtained via VANETs. Several protocol design weaknesses of the ETSI ITS approach have been identified. It is found that the standardized way of cross layer message assembly leads to frequent violation of low layers’ maximum packet size restrictions. This causes inabilities to distribute important data sets from the application layer. Furthermore, confidential end-to-end encrypted communication over a multi-hop connection is impossible, as forwarders cannot access required routing information. This is caused by incorrect data encryption rules. Approaches to overcome the found shortcomings are proposed and evaluated. To overcome the outlined security issues, several improvements have been proposed. These include, 1. secure time synchronization among nodes, but current mechanisms can hardly provide it, 2. caching of multiple pseudonym certificates being valid during the same time span is to be avoided, 3. pre-caching of pseudonym certificates valid in the future is to be limited to a minimum, 4. presence of constant but distinctive data sets within VANET messages has to be avoided to enable privacy conserving pseudonym changes, 5. mechanisms for limiting the channel load caused by certificate distribution are required, especially a. after a pseudonym change the number of superficial pseudonym certificate distributions due to new neighbor detection should be limited by using explicit signaling of the change, b. sending of certificate chains should be removed altogether, instead individual dissemination should be used for CA certificates, and c. the number of CA certificate deliveries after a request for such a kind of certificate should be limited to a minimum by using targeted requests. By employing the given improvements most of the found security weaknesses can be overcome (issues 1, 2 and 3c). For the remaining weaknesses the required capabilities for a successful attack can be made significantly more challenging.
2

A RoundD-like Roundabout Scenario in CARLA Simulator

Nadar, Ali, Lafon, Mathis, Härri, Jérôme 23 June 2023 (has links)
Evaluating the challenges and opportunities of cooperative autonomous vehicles (CAV) require an adapted simulation methodology reproducing realistic driving and sensory contexts. In this paper, we propose a RounD-like CARLA scenario reproducing in CARLA the driving context recorded in the RounD dataset. We focus in particular on roundabout scenarios, as they are considered particularly challenging for CAV. We present the methodology followed to generate the CARLA scenario and describe challenges to reproduce trajectories corresponding to RounD. Origin and destination of vehicles, waypoint and speed are extracted from RounD for CARLA vehicles to closely reproduce the driving patterns observed in RounD. The benefit of such scenario are manyfold, such as evaluating control algorithms of CAVs, deep AI reinforcement learning, or vehicular sensor data sampling under realistic driving contexts. It notably will reduce the gap of AI mechanisms for CAV between simulation scenarios and realistic conditions.
3

Impact of C-ITS on Mobility and Society

Tägtström, Ninnie January 2023 (has links)
This thesis investigates the important potential of Cooperative Intelligent Transport Systems (C-ITS) onmobility and society. C-ITS appears as a promising solution to reinvent transportation and become avital part of the ever-evolving environment as developments in technology continue to change the world.The goal of this study is to investigate how C-ITS can enhance and promote various forms of mobility.It additionally investigates at how C-ITS applications and policy objectives interact, highlighting C-ITS’contribution to the development of a sustainable society.A thorough examination of the current literature, case studies, and pertinent policies was conductedin order to analyse the possible advantages and difficulties related to C-ITS in detail. In order toprovide seamless communication and interaction between C-ITS systems and other devices, the researchemphasizes the importance of early integration and adoption of C-ITS as a solution. It also emphasizesthe need for standardization, interoperability, and collaborative efforts among stakeholders.Findings demonstrate that C-ITS has the capacity to support policies aimed at improving transportationsystems and mobility in the cities. C-ITS usage has enormous potential for influencing society andmobility. C-ITS reduces accidents while enhancing road safety through real-time communication. Byenhancing traffic flow and promoting alternative modes of transportation, it supports environmentalsustainability. It also has secondary effects such as reducing pollutants and improving air andnoise quality. Through the integration of numerous mobility choices and the provision of real-timeinformation, C-ITS improves accessibility. For implementation to be successful, privacy and securityissues as well as economic reasons must be taken into consideration. To solve the issues posed byconcerns about data privacy, security, and economic factors, however, strong policies, legislation,and safe data processing techniques are needed. C-ITS has the potential to help create a future oftransportation that is safer, more environmentally friendly, and more effective.In the concluding part, the paper suggests numerous possibilities for C-ITS research going forward.It advises combining policies and guiding documents to offer a clearer strategy for utilizing C-ITSsuccessfully. Additionally, creating more complex mathematical models that include equations can helpus comprehend the importance of the variables better. Iterative procedures integrated into detailedmodels allow for the comparison of many scenarios, addressing the various desires of stakeholders andexperts. Additionally, combining C-ITS with Vehicle-to-Everything (VoT) systems offer a chance toinvestigate the real advantages and make it simpler to make comparisons with other variables. Furtherresearch should be carried out on the likelihood of developing an automated mobility system.
4

Safety of Cooperative Automated Driving : Analysis and Optimization

Sidorenko, Galina January 2022 (has links)
New cooperative intelligent transportation system (C-ITS) applications become enabled thanks to advances in communication technologies between vehicles(V2V) and with the infrastructure (V2I). Communicating vehicles share information with each other and cooperate, which results in improved safety, fuel economy, and traffic efficiency. An example of a C-ITS application is platooning, which comprises a string of vehicles that travel together with short inter-vehicle distances (IVDs). Any solution related to C-ITS must comply with high safety requirements in order to pass standardization and be commercially deployed. Furthermore, trusted safety levels should be assured even for critical scenarios. This thesis studies the conditions that guarantee safety in emergency braking scenarios for heterogeneous platooning, or string-like, formations of vehicles. In such scenarios, the vehicle at the head of the string emergency brakes and all following vehicles have to automatically react in time to avoid rear-end collisions. The reaction time can be significantly decreased with vehicle-to-vehicle (V2V) communication usage since the leader can explicitly inform other platooning members about the critical braking. The safety analysis conducted in the thesis yields computationally efficient methods and algorithms for calculating minimum inter-vehicle distances that allow avoiding rear-end collisions with a predefined high guarantee. These IVDs are theoretically obtained for an open-loop and a closed-loop configurations. The former implies that follower drives with a constant velocity until braking starts, whereas in the latter, an adaptive cruise control (ACC) with a constant-distance policy serves as a controller. In addition, further optimization of inter-vehicle distances in the platoon is carried out under an assumption of centralized control. Such an approach allows achieving better fuel consumption and road utilization. The performed analytical comparison suggests that our proposed V2V communication based solution is superior to classical automated systems, such as automatic emergency braking system (AEBS), which utilizes only onboard sensors and no communication. Wireless communication, enabling to know the intentions of other vehicles almost immediately, allows for smaller IVDs whilst guaranteeing the same level of safety. Overall, the presented thesis highlights the importance of C-ITS and, specifically, V2V in the prevention of rear-end collisions in emergency scenarios. Future work directions include an extension of the obtained results by considering more advanced models of vehicles, environment, and communication settings; and applying the proposed algorithms of safety guaranteeing to other controllers, such as ACC with a constant time headway policy.
5

Designing Multimodal Warning Signals for Cyclists of the Future

Nordmark, Anton January 2019 (has links)
Traffic is a complex environment in which many actors take part; several new technologies bring promises of reducing this complexity. However, cyclists—a particularly vulnerable road user group—have so far been somewhat put aside in these new developments, among them being Cooperative Intelligent Traffic Systems (C-ITS) and their aspects of human–computer interaction. This master’s thesis of industrial design engineering presents five multimodal collision warning signals for cyclists—future ones in these supposed C-ITS—using a novel application of bone conduction headphones (BCH) via sensations of both sound and touch. The thesis project was conducted as a complementary subset of the larger research project ‘V2Cyclist’ orchestrated by RISE Interactive. V2Cyclist set out to adapt the wireless V2X-protocol for cyclists by developing a physical prototype in the form of a bicycle helmet and corresponding human–computer interface. A significant part of the theoretical framework for this thesis was multiple resource theory: tasks in a different modality can be performed more effectively than in one already taxed attentively. Literature on human factors was also applied, particularly with regards to the perception of sound; evidence suggests that humans evolved a perceptual bias for threatening and ‘looming’ sounds that appear to encroach our peripersonal space; ethological findings point toward the association with low-frequency sounds to largeness. Sound design techniques usually applied to more artistic ends, such as synthesis and mixing, were repurposed for the novel, audiotactile context of this thesis. The thesis process was rooted in design thinking and consisted of four stages: context immersion, ideation, concept development, and lastly evaluation; converging and diverging the novel design space of using BCH in an audiotactile, i.e. bimodal way. The divergent approach generated a wide range of ideas. The later convergent approach did not result in one, definite design as further evaluation is required but also due to unknowns in terms of future hardware and network constraints. Given the plurality and diversity of cyclists, it may well follow that there is no optimal collision warning design in the singular. Hence, a range of five different solutions is presented. Each of the five multimodal collision warnings presents a different approach to conveying a sense of danger and urgency. Some warning signals are static in type, while others are more dynamic. Given the presumed rarity of collision warnings, multiple design techniques and rationales were applied separately, as well as in combination, to create different warning stimuli that signaled high urgency in an intuitive way. Namely, the use of: conventions in design and culture; explicitness in the form of speech; visceral appeal via threatening and animalistic timbres; dynamic and procedurally generated feedback; multimodal salience; crossmodal evocation of ‘roughness;’ size-sound symbolism to imply largeness; and innately activating characteristics of looming sounds. / Trafiken är en komplex miljö med många deltagare; diverse ny teknik gör anspråk på att underlätta denna komplexitet. Men, cyklister—en särskilt utsatt grupp av trafikanter—har hittills hamnat i skymundan för sådana utvecklingar. Vidare, aspekten av användbara gränssnitt för cyklister inom sådana uppkopplade och samverkande trafiksystem (C-ITS) har utforskats desto mindre. Det här examensarbetet inom Teknisk design presenterar fem multimodala kollisionsvarningar avsedda för cyklister—framtida sådana i dessa C-ITS—genom en ny och bimodal användning av benledande hörlurar via både ljud och vibrationer. Examensarbetet genomfördes i koppling till forskningsprojektet V2Cyclist, orkestrerat av RISE Interactive, vars projektmål var att anpassa det trådlösa kommunikationsprotokollet V2X för cyklister via en fysisk prototyp i form av en cykelhjälm och parallellt utveckla ett tillhörande användargränssnitt. En viktig del av det teoretiska ramverket för det här examensarbetet grundar sig på multiple resource theory: uppgifter kan utföras mer effektivt i en annan modalitet än i en som redan är belastad med uppmärksamhet. Mänskliga faktorer och teori om vår uppfattning användes; bevis pekar på att människor har evolutionärt utvecklat en bias för hotande ljud som upplevs inkräkta på vårt närmsta personliga revir; etologiska rön visar på en koppling mellan lågfrekventa ljud och ‘storhet.’ Tekniker inom ljuddesign vanligtvis använda till mer artistiska ändamål, såsom syntes och mixning, användes här till godo för att utforska den nya och bimodala designrymden. Processen för arbetet grundade sig i design thinking och bestod av fyra faser: kontextfördjupning, idégenerering, konceptutveckling, och utvärdering. En ny och tidigare outforskad designrymd beståendes av en bimodal, ljudtaktil användning av benledande hörlurar divergerades och konvergerades. Ett initialt utforskande angreppssätt gav upphov till en bred mängd av idéer. Ett senare renodlande angreppssätt gick, dock, inte hela vägen till endast en optimal lösning, då vidare utvärdering krävs men också på grund av okända teknologiska begränsningar. Dessutom, givet cyklisters stora mångfald, kan det möjligtvis följa att det inte finns någon enskild design av den optimala kollisionsvarningen. Ett spann på fem olika lösningar presenteras därmed. Fem koncept för multimodala kollisionsvarningar presenteras där varje variant uttrycker fara och kritiskhet på olika sätt. Vissa är statiska i typ, medan andra verkar mer kontinuerligt och dynamiskt. Det antogs att kollisionsvarningar sker sällan. Olika designtekniker och motiveringar har använts, ibland i kombination med varandra, för att skapa kollisionsvarningar vars avsikter omedelbart förstås: normer inom design och kultur gällande ljud; uttalad kommunikation i form av tal; anspråk på människors biologiska intuition via hotfulla och djurliknande klangfärger; dynamisk och procedurellt genererad feedback; multimodal effektfullhet; korsmodal känsla av grova texturer; size-sound symbolism för att antyda ‘storhet;’ samt de naturligt aktiverande egenskaperna hos looming sounds.
6

Local Traffic Safety Analyzer – Improved Road Safety and Optimized Signal Control for Future Urban Intersections

Eggers, Kim Jannik, Oertel, Robert, Hesse, Martin 23 June 2023 (has links)
Improving road safety and optimizing the traffic flow – these are major challenges at urban intersections. In particular, strengthening the needs of vulnerable road users (VRUs) such as pedestrians, cyclists and e-scooter drivers is becoming increasingly important, combined with support for automated and connected driving. In the LTSA project, a new system is being developed and implemented exactly for this purpose. The LTSA is an intelligent infrastructure system that records the movements of all road users in the vicinity of an intersection using a combination of several locally installed sensors e.g. video, radar, lidar. AI-based software processes the detected data, interprets the movement patterns of road users and continuously analyzes the current traffic situation (digital twin). Potentially dangerous situations are identified, e.g. right turning vehicles and simultaneously crossing VRUs, and warning messages can be sent to connected road users via vehicle-to-infrastructure communication (V2X). Automated vehicles can thus adapt their driving maneuvers. In addition, the collected data is applied to improve traffic light control depending on the current traffic situation, especially for VRUs. This abstract describes the LTSA system and its implementation in the German city of Potsdam. The current project state is presented and an outlook on next steps is given.
7

Etude des interactions réseaux véhiculaires et Cloud / Study of VANETs and Cloud interactions

Wilhelm, Geoffrey 06 December 2018 (has links)
Les réseaux véhiculaires sont des réseaux émergents qui permettent de connecter des véhicules entre eux et avec les infrastructures routières. Ils permettent de mettre en œuvre des applications de sécurité (évitement des collisions, prévention des travaux, etc.), des applications temps-réel (aide à la conduite automatisée), des applications des systèmes de transport intelligents (gestion du trafic, proposition de détours, etc.), des applications de confort (péage automatique des autoroutes, connexion à du contenu multimédia en ligne, etc.). Pour fonctionner pleinement, le véhicule a besoin d’une puissance de calcul de plus en plus grande et d’une connexion quasi-continue. Afin de garantir cette contrainte, les réseaux véhiculaires font de plus en plus appel au Cloud. Cette thèse vise à explorer les différentes interactions entre les réseaux véhiculaire et Cloud. / Vehicular Ad-hoc Networks (VANETs) are a new kind of networks which allow to connect vehicles between them and with the road infrastructures. It make possible to deploy safety applications (colision avoidance, roadworks advertisement, etc.), real time application (driver assistance, automated driving, etc.), comfort application (automatic toll payment, access to multimedia contents via internet, etc.). In order to be functioning completely, the vehicle needs more and more computing power and a connection with almost no interruption. To guarantee this constraints, VANETs are using more and more often the Cloud Computing. This thesis aims to explore the differents intereactions between VANETs and the Cloud
8

Localisation et transmissions sécurisées pour la communication Véhicule à Infrastructure (V2I) : Application au service de télépéage ITS-G5 / Localization and secure transmissions for Vehicle to Infrastructure communication (V2I) : Application to the electronic toll service using the ITS-G5 technology

Randriamasy, Malalatiana 24 May 2019 (has links)
La localisation précise des véhicules et la sécurité des échanges sont deux grands axes qui font la fiabilité des services fournis dans les systèmes de transport intelligent. Ces dernières années, elles font l’objet de nombreux projets de recherche pour des champs d’application divers. Dans cette thèse, le contexte d’application est la réalisation d’un service de télépéage utilisant la technologie ITS-G5. Cette technologie de communication sans-fil permet dans un premier temps le partage des informations de sécurité routière entre les véhicules (V2V), le véhicule et l’infrastructure (V2I). Dans cette thèse, on propose une architecture permettant d’échanger des transactions de télépéage utilisant les équipements communicants en ITS-G5 embarqués dans les véhicules connectés et les unités bord de route (UBR) de l’infrastructure. Les problématiques de nos travaux de recherche se concentrent sur la méthode de localisation des véhicules ayant effectué la transaction afin de pouvoir la valider et sur la sécurité de l’architecture proposée pour assurer l’échange de cette transaction. Afin de bien localiser les véhicules lors du passage au péage, notre approche propose la compréhension de la cinématique du véhicule par une modélisation adéquate à partir des données recueillies dans les messages coopératifs (CAM : Cooperative Awareness Message) en approche du péage. Cela améliorera les informations de géolocalisation déjà présentes. Notre objectif est d’arriver à une précision de moins d’un mètre pour distinguer 2 véhicules adjacents. D’autre part, le protocole de sécurité proposé permet d’assurer l’authentification des équipements participant à l’échange et à la validation de la transaction, l’intégrité des données échangées ainsi que la confidentialité des échanges compte tenu du contexte de communication sans-fil et de la sensibilité des données échangées. Une preuve de concept de la solution de télépéage utilisant la technologie ITS-G5 est développée et intègre nos deux contributions. / The precise localization of vehicles and the security of communication are requirements that make almost of the services provided in intelligent transport systems (ITS) more reliable. In recent years, they have been the subject of numerous research projects for various fields of application. In this thesis, the context is the development of an electronic toll service using the ITS-G5 technology. This wireless communication technology initially allows the sharing of traffic safety information between vehicles (V2V), vehicle and infrastructure (V2I). In our work, we propose a tolling application using equipment operating in ITS-G5 embedded in the connected vehicles and roadside units. For this, ensuring both precise geolocation of the vehicles and security of communication are required to validate the transaction.In order to properly locate the vehicles during the toll crossing, our approach is based on the understanding of the kinematics of the vehicle through a suitable modeling from the data collected in the cooperative messages (called CAM: Cooperative Awareness Message). This approach aims to improve the geolocation information already present in the message. Our goal is to achieve vehicle localization with an accuracy lower than one meter to distinguish two adjacent vehicles. On the other hand, the proposed tolling protocol ensures the authentication of the equipment or entities involved in the exchange and the validation of the transaction, the integrity of the transmitted data as well as the confidentiality of the communication. In this way, we take into account the context of the wireless communication and the sensitivity of the exchanged data. Our two contributions are integrated in the implemented Proof of Concept of the tolling application using the ITS-G5 technology.

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