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Estratégias de beaconing para comunicação em redes veiculares; Beaconing strategies for communication in vehicular networks

Yokoyama, Roberto Sadao
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 11/07/2014 Português
Relevância na Pesquisa
57.99913%
Em sistemas de transporte inteligentes, as redes veiculares têm um papel fundamental. Por meio da comunicação sem fio, veículos irão disseminar conteúdo nessas redes para melhorar a segurança e eficiência no transporte, prover aplicações de entretenimento etc. Beaconing, proposto originalmente para aplicações de segurança, é usado neste estudo como uma das maneiras de disseminação de conteúdo, onde o nó emissor insere uma informação em um quadro de beacon, que é propagado em broadcast. A maioria dos estudos da literatura focam na otimização de desempenho de beaconing e utilizam o método de simulação para validação e avaliação. Esta tese explora estratégias de beaconing com validação e avaliação usando método experimental em ambientes reais para resolver problemas relacionados a aplicações cooperativas de localização e posicionamento de veículos. Para tanto, foi implantado um testbed veicular para realização de testes tradicionais, como o de desempenho sobre os parâmetros de comunicação, mas principalmente de novos protocolos que transmitem informações adicionais nos beacons. Os principais resultados são: i) uma aplicação para inferência da distância entre os veículos por meio do sinal recebido de rádio frequência...

Uma arquitetura de gerência de mobilidade para redes veiculares; An architecture for mobility management for vehicular network

Rodolfo Ipolito Meneguette
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 16/12/2013 Português
Relevância na Pesquisa
48.39298%
Redes Ad Hoc Veiculares (VANETs) constituem uma subclasse das redes Ad Hoc móveis que provê uma conexão sem fio entre veículos bem como entre veículos e dispositivos de acostamento. Essas redes proveem aplicações que focam na segurança do condutor, em fornecer maior eficiência do tráfego dos veículos nas vias públicas e em trazer algum conforto e entretenimento para os passageiros ao longo de sua viagem. Algumas dessas aplicações precisam estar conectadas com a internet através de um ponto de acesso que encontra-se no acostamento, como uma torre celular ou uma torre WiFi. Essa conexão pode gerar uma sobrecarga de mensagens de controle e pode sofrer uma troca de ponto de acesso que impacta no desempenho da aplicação. Além da interface de conexão com o ponto de acesso, o veículo é equipado com várias outras interfaces de redes vinculadas a diferentes tecnologias, podendo tirar vantagens do uso simultâneo dessas diversas interfaces de rede, com isso, maximizando a vazão e diminuindo a latência. Entretanto, esse uso pode aumentar ainda mais a sobrecarga das mensagens de controle, tendo como consequencia o aumento do tempo de troca de um ponto de acesso a outro, afetando a vazão da rede e o seu desempenho. Para superar esses desafios e prover uma boa qualidade de serviço para a aplicação...

Towards a network management solution for vehicular delay-tolerant networks

Ferreira, Bruno Filipe Aguiar Durães
Fonte: Universidade da Beira Interior Publicador: Universidade da Beira Interior
Tipo: Dissertação de Mestrado
Publicado em //2012 Português
Relevância na Pesquisa
48.33717%
Vehicular networks appeared as a new communication solution where vehicles act as a communication infrastructure, providing data communications through vehicle-to-vehicle (V2V) or vehicle-to-infrastructure (V2I) communications. Vehicular Delay-Tolerant Networks (VDTNs) are a new disruptive network architecture assuming delay tolerant networking paradigm where there are no end-to-end connectivity. In this case the incial node transmits the data to a closed node, the data will be carried by vehicles, hop to hop until the destination. This dissertation focuses on a proposal of a network management solution, based standard protocol Simple Network Management Protocol (SNMP) to VDTN networks. The developed solution allows control a VDTN netowork through a Network Management System (NMS) with the objective to detect and, if it’s possible, anticipate, possible errors on network. The research methodology used was the prototyping. So, it was built a network management module to the laboratorial prototype, called VDTN@Lab. The system built include a MIB (Management Information Base) placed in all vehicular network nodes. The solution was built, demonstrated, validated and evaluated their performance, being ready for use.

Disorder analytic model-based CMT algorithms in vehicular sensor networks

Xu, Changqiao; Xia, Xiangzhou; Guan, Jianfeng; Zhang, Hongke; Muntean, Gabriel-Miro
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: info:eu-repo/semantics/article; all_ul_research; ul_published_reviewed
Português
Relevância na Pesquisa
47.99913%
peer-reviewed; Recently, vehicular sensor networks (VSNs) have emerged as a new intelligent transport networking paradigm in the Internet of Things. By sensing, collecting, and delivering traffic-related information, VSNs can significantly improve both driving experience and traffic flow control, especially in constrained urban environments. Latest technological advances enable vehicular devices to be equipped with multiple wireless interfaces, which can support cooperative communications for concurrent multipath transfer (CMT) in VSNs. However, path heterogeneity and vehicle mobilitycause CMT not to achieve the same high transport efficiency recorded in wired nonmobile network environments. This paper proposes a novel vehicular network-based CMT solution (VNCMT) to address the above issues and improve data delivery efficiency. VN-CMT is based on a CMTdisorder analytic model which can effectively and accurately evaluate the degree of out-of-order data. Based on this proposed model, a series of mechanisms are introduced as follows: (1) a packet disorder-reducing retransmission policy to reduce retransmission delay; (2) a path group selection algorithm to find the best path set for data multipath concurrent transfer; and (3) a data scheduling mechanism to distribute data according to each path’s capacity. Simulation results show how VN-CMT improves data delivery efficiency in comparison with an existing state-of-the-art solution.

QoE-driven user-centric VoD services in urban multi-homed P2P-based vehicular networks

Xu, Changqiao; Zhao, Futao; Guan, Jianfeng; Zhang, Hongke; Muntean, Gabriel-Miro
Fonte: IEEE Computer Society Publicador: IEEE Computer Society
Tipo: info:eu-repo/semantics/article; all_ul_research; ul_published_reviewed
Português
Relevância na Pesquisa
58.18858%
peer-reviewed; Recently many cities around the world have witnessed large scale deployment of terrestrial broadcasting mobile TV to vehicles. This service is similar to the cable or satellite television already watched at home and user-centric interactive mobile Video-on-Demand (VoD) over urban vehicular networks is in fact expected. However providing this new service with focus on user Quality of Experience (QoE) constitutes a significant challenge. This paper introduces a QoE-driven User-centric solution for VoD services in urban vehicular network environments (QUVoD). QUVoD relies on a multi-homed hierarchical peer-topeer (P2P) and vehicular ad-hoc network (VANET) architecture. Vehicles construct a low layer VANET via WAVE interfaces and also form an upper layer P2P Chord overlay on top of a cellular network via 4G interfaces. A novel grouping-based storage strategy is proposed which distributes uniformly the video segments along the Chord overlay, reducing segment seeking traffic, while also enabling load-balancing. A novel segment seeking and multipath delivery scheme is also introduced which achieves high lookup success rate and very good video data delivery efficiency. Furthermore, a new speculation-based prefetching strategy is proposed...

VARON: Vehicular Ad-hoc Route Optimisation for NEMO

Bernardos, Carlos J.; Soto, Ignacio; Calderón, María; Boavida, Fernando; Azcorra, Arturo
Fonte: Elsevier Publicador: Elsevier
Tipo: Conferência ou Objeto de Conferência Formato: application/pdf
Publicado em //2007 Português
Relevância na Pesquisa
37.939646%
In this paper we analyse the provision of enhanced communications between vehicles. It is expected that vehicles will have several communication devices, and that a specialised node will provide external connectivity to these devices, i.e. the devices in the vehicle form a Mobile Network. We propose the use of Network Mobility communication solutions for providing access from the vehicles to an infrastructured network (e.g., the Internet) or for communication with other vehicles. The main contribution of this paper consists in a route optimisation solution for mobile networks – based on the use of mixed ad-hoc and infrastructure communications – that enables inter-vehicle communications to be improved in terms of bandwidth and delay. The mechanism provides the same level of security than today’s IPv4 Internet, by means of reusing Mobile IPv6 security concepts, and the use of public key cryptography and Cryptographically Generated Addresses. The proposed solution is characterised and evaluated through extensive simulation, showing that it provides an efficient optimisation in vehicular communications.

VARON: Vehicular Ad hoc Route Optimisation for NEMO

Bernardos, Carlos J.; Soto, Ignacio; Calderón, María; Boavida, Fernando; Azcorra, Arturo
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Artigo de Revista Científica Formato: aplication/PDF
Português
Relevância na Pesquisa
37.939646%
In this paper, we analyse the provision of enhanced communications between vehicles. It is expected that vehicles will have several communication devices, and that a specialised node will provide external connectivity to these devices, i.e., the devices in the vehicle form a Mobile Network. We propose the use of Network Mobility communication solutions for providing access from the vehicles to an infrastructured network (e.g., the Internet) or for communication with other vehicles. The main contribution of this paper consists in a route optimisation solution for mobile networks - based on the use of mixed ad hoc and infrastructure communications - that enables inter-vehicle communications to be improved in terms of bandwidth and delay. The mechanism provides the same level of security than today's IPv4 Internet, by means of reusing Mobile IPv6 security concepts, and the use of public key cryptography and Cryptographically Generated Addresses. The proposed solution is characterised and evaluated through extensive simulation, showing that it provides an efficient optimisation in vehicular communications.; http://www.sciencedirect.com/science/article/B6TYP-4N3GFKC-1/1/d7641ab7fb03454de3a4ebb693d8cdeb

REINVENT : accessing vehicular networks in mobile application; REINVENT : solução para uso de redes veiculares em aplicações móveis

Oliveira, Filipe Ferreira de
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Dissertação de Mestrado
Português
Relevância na Pesquisa
38.232505%
As redes veiculares têm sido alvo de grandes avanços tecnológicos, e a comunicação entre veículos é hoje uma realidade que tem despertado o interesse tanto ao nível da investigação como de alguns dos principais fabricantes de automóveis com o intuito de criar um conjunto de serviços para melhorar a experiência dos utilizadores deste tipo de redes. Por outro lado, os dispositivos móveirs como smartphones, tablets ou PDA’s também são uma área emergente no mundo das tecnologias devido ao enorme aumento de capacidade computacional que sofreram nos últimos anos. Embora as redes veiculares tenham sido alvo de grandes avanços tecnológicos continuam a encontrar obstáculos para a sua afirmação devido à indisponibilidade de dispositivos nos veículos que permitam usufruir das suas potencialidades. Esta falta de dispositivos pode ser ultrapassada aliando o mundo dos dispositivos móveis com as redes veiculares. Utilizando o potencial das redes veiculares e a capacidade computacional dos novos dispositivos móveis pode-se explorar um cenário de criação de serviços e aplicações de segurança, controlo e eficiência de tráfego e entretenimento. O presente trabalho propõe-se a estudar, criar e testar uma solução para a integração das duas áreas tecnológicas referidas anteriormente. Neste documento é descrita uma arquitectura de alto nível que permite a integração de aplicações móveis com as redes veiculares...

Performance evaluation of a cooperative reputation system for vehicular delay-tolerant networks

Dias, João A.F.F.; Rodrigues, Joel; Shu, Lei; Ullah, Sana
Fonte: SpringerOpen Publicador: SpringerOpen
Tipo: Artigo de Revista Científica
Publicado em //2014 Português
Relevância na Pesquisa
38.189014%
In the last decade, both scientific community and automotive industry enabled communications among vehicles in different kinds of scenarios proposing different vehicular architectures. Vehicular delay-tolerant networks (VDTNs) were proposed as a solution to overcome some of the issues found in other vehicular architectures, namely, in dispersed regions and emergency scenarios. Most of these issues arise from the unique characteristics of vehicular networks. Contrary to delay-tolerant networks (DTNs), VDTNs place the bundle layer under the network layer in order to simplify the layered architecture and enable communications in sparse regions characterized by long propagation delays, high error rates, and short contact durations. However, such characteristics turn contacts very important in order to exchange as much information as possible between nodes at every contact opportunity. One way to accomplish this goal is to enforce cooperation between network nodes. To promote cooperation among nodes, it is important that nodes share their own resources to deliver messages from others. This can be a very difficult task, if selfish nodes affect the performance of cooperative nodes. This paper studies the performance of a cooperative reputation system that detects...

Towards a network management solution for vehicular delay-tolerant networks

Ferreira, Bruno Filipe Aguiar Durães
Fonte: Universidade da Beira Interior Publicador: Universidade da Beira Interior
Tipo: Dissertação de Mestrado
Publicado em //2012 Português
Relevância na Pesquisa
48.33717%
Vehicular networks appeared as a new communication solution where vehicles act as a communication infrastructure, providing data communications through vehicle-to-vehicle (V2V) or vehicle-to-infrastructure (V2I) communications. Vehicular Delay-Tolerant Networks (VDTNs) are a new disruptive network architecture assuming delay tolerant networking paradigm where there are no end-to-end connectivity. In this case the incial node transmits the data to a closed node, the data will be carried by vehicles, hop to hop until the destination. This dissertation focuses on a proposal of a network management solution, based standard protocol Simple Network Management Protocol (SNMP) to VDTN networks. The developed solution allows control a VDTN netowork through a Network Management System (NMS) with the objective to detect and, if it’s possible, anticipate, possible errors on network. The research methodology used was the prototyping. So, it was built a network management module to the laboratorial prototype, called VDTN@Lab. The system built include a MIB (Management Information Base) placed in all vehicular network nodes. The solution was built, demonstrated, validated and evaluated their performance, being ready for use.

Construction of a real vehicular delay-tolerant network testbed

Paula, Maicke Cabral Gomes de
Fonte: Universidade da Beira Interior Publicador: Universidade da Beira Interior
Tipo: Dissertação de Mestrado
Publicado em //2011 Português
Relevância na Pesquisa
38.189014%
Vehicular Delay-Tolerant Networks (VDTNs) appear as innovative network architecture, able to outline communication challenges caused by issues like variable delays, disruption and intermittent connectivity once that it utilizes the store-carry-and-forward method to allow that in-transit messages (called bundles) can be delivered to the destination by hopping over the mobile vehicles even that an end-to-end path does not exist. Since messages are stored persistently in a buffer and forward to the next hop, a new communication infrastructure is created allowing low-cost asynchronous opportunistic communication under the most critical situations like variable delays and bandwidth constraints. VDTN introduces a layered architecture, acting as an overlay network over the link layer, aggregating incoming IP packets in data bundles (large IP packets), using out-of-band signaling, based on the separation of the control plane and planes. This dissertation presents and evaluates the performance of a real VDTN testbed, demonstrating the real applicability of this new vehicular communication approach. It includes an embedded VDTN testbed created to evaluate safety systems in a real-world scenario. It was used cars with laptops to realize terminal and relay nodes. A real testbed is very important because some complex issues presented in vehicular communication systems can be treated with more realism in real-world environments than in a laboratory environment. The experiments were performed on the internal streets of Brazilian Fiat Automobile manufacturing plant. Performance measurements and analysis were also conduct to verify the efficiency of the system. The results obtained show that safety applications and services can be executed with the actual proposal VDTN architecture in several environments...

Content storage and retrieval mechanisms for vehicular delay-tolerant networks

Silva, Bruno Miguel Correia
Fonte: Universidade da Beira Interior Publicador: Universidade da Beira Interior
Tipo: Dissertação de Mestrado
Publicado em //2010 Português
Relevância na Pesquisa
38.219841%
Vehicular delay-tolerant networks (VDTNs) were proposed as a novel disruptive network concept based on the delay tolerant networking (DTN) paradigm. VDTN architecture uses vehicles to relay messages, enabling network connectivity in challenging scenarios. Due to intermittent connectivity, network nodes carry messages in their buffers, relaying them only when a proper contact opportunity occurs. Thus, the storage capacity and message retrieving of intermediate nodes directly affects the network performance. Therefore, efficient and robust caching and forwarding mechanisms are needed. This dissertation proposes a content storage and retrieval (CSR) solution for VDTN networks. This solution consists on storage and retrieval control labels, attached to every data bundle of aggregated network traffic. These labels define cacheable contents, and apply cachecontrol and forwarding restrictions on data bundles. The presented mechanisms gathered several contributions from cache based technologies such as Web cache schemes, ad-hoc and DTN networks. This solution is fully automated, providing a fast, safe, and reliable data transfer and storage management, while improves the applicability and performance of VDTN networks significantly. This work presents the performance evaluation and validation of CSR mechanisms through a VDTN testbed. Furthermore it presents several network performance evaluations and results using the well-known DTN routing protocols...

VIP-WAVE: On the Feasibility of IP Communications in 802.11p Vehicular Networks

Cespedes, Sandra; Lu, Ning; Shen, Xuemin
Fonte: Universidade Icesi Publicador: Universidade Icesi
Português
Relevância na Pesquisa
48.189014%
Vehicular communication networks, such as the 802.11p and Wireless Access in Vehicular Environments (WAVE) technologies, are becoming a fundamental platform for providing real-time access to safety and entertainment information. In particular, infotainment applications and, consequently, IP-based communications, are key to leverage market penetration and deployment costs of the 802.11p/WAVE network. However, the operation and performance of IP in 802.11p/WAVE are still unclear as the WAVE standard guidelines for being IP compliant are rather minimal. This paper studies the 802.11p/WAVE standard and its limitations for the support of infrastructure-based IP applications, and proposes the Vehicular IP in WAVE (VIP-WAVE) framework. VIP-WAVE defines the IP configuration for extended and non-extended IP services, and amobilitymanagement scheme supported by Proxy Mobile IPv6 over WAVE. It also exploits multihop communications to improve the network performance along roads with different levels of infrastructure presence. Furthermore, an analytical model considering mobility, handoff delays, collisions, and channel conditions is developed for evaluating the performance of IP communications in WAVE. Extensive simulations are performed to demonstrate the accuracy of our analytical model and the effectiveness of VIP-WAVE in making feasible the deployment of IP applications in the vehicular network. © 2012 IEEE.

Modelos de comportamiento de las redes vehiculares en sus escenarios más representativos, utilizando simulación en la herramienta NCTUns; Behavioral models for typical scenarios in vehicular networks: simulation in NCTUns.

Pachón de la Cruz, Alvaro; Nieto, Carlos Felipe; Velasco Vivas, María Lucía
Fonte: Universidad Icesi; Facultad de Ingeniería Publicador: Universidad Icesi; Facultad de Ingeniería
Tipo: article; Artículo Formato: PDF; p.13-25; Electrónico
Português
Relevância na Pesquisa
47.8986%
Las redes vehiculares se constituyen en un tipo de redes que permiten establecer comunicación entre conductores y pasajeros de vehículo a vehículo o entre vehículo e infraestructura, sin tener que implementar estructura adicional. Los principales objetivos de este tipo de redes son mejorar la seguridad en las vías y la eficiencia en el transporte al generar mayor comodidad para los usuarios. En este artículo se realiza una breve descripción del estado de arte de este tipo de redes y los avances alcanzados. Al mismo tiempo, se hace un análisis de su funcionamiento a través de modelos diseñados y simulados en la herramienta NCTUns que consideran la disposición y trazado en ciudades típicas de Colombia.; Vehicular networks allow drivers and passengers in moving vehicles to communicate from vehicle to vehicle, or from vehicle to a existing infrastructure, without the need for additional hardware. The main goals for these networks are to improve road safety and transportation efficiency. This article briefly describes the state-of-the-art and new achievements in the vehicular network field, and shows the analysis of the behavior of such networks through the use of simulation models deployed in the NCTUns simulation tool...

Vehicular Ad Hoc and Sensor Networks; Principles and Challenges

Piran, Mohammad Jalil; Murthy, G. Rama; Babu, G. Praveen
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 13/08/2011 Português
Relevância na Pesquisa
38.286875%
The rapid increase of vehicular traffic and congestion on the highways began hampering the safe and efficient movement of traffic. Consequently, year by year, we see the ascending rate of car accidents and casualties in most of the countries. Therefore, exploiting the new technologies, e.g. wireless sensor networks, is required as a solution of reduction of these saddening and reprehensible statistics. This has motivated us to propose a novel and comprehensive system to utilize Wireless Sensor Networks for vehicular networks. We coin the vehicular network employing wireless Sensor networks as Vehicular Ad Hoc and Sensor Network, or VASNET in short. The proposed VASNET is particularly for highway traffic .VASNET is a self-organizing Ad Hoc and sensor network comprised of a large number of sensor nodes. In VASNET there are two kinds of sensor nodes, some are embedded on the vehicles-vehicular nodes- and others are deployed in predetermined distances besides the highway road, known as Road Side Sensor nodes (RSS). The vehicular nodes are used to sense the velocity of the vehicle for instance. We can have some Base Stations (BS) such as Police Traffic Station, Firefighting Group and Rescue Team. The base stations may be stationary or mobile. VASNET provides capability of wireless communication between vehicular nodes and stationary nodes...

A Seamless Flow Mobility Management Architecture for Vehicular Communication Networks

Meneguette, Rodolfo I.; Bittencourt, Luiz F.; Madeira, Edmundo R. M.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 03/04/2013 Português
Relevância na Pesquisa
38.071736%
Vehicular Ad Hoc Networks (VANETs) are self-organizing, self-healing networks which provide wireless communication among vehicular and roadside devices. Applications in such networks can take advantage of the use of simultaneous connections, thereby maximizing the throughput and lowering latency. In order to take advantage of all radio interfaces of the vehicle and to provide good quality of service for vehicular applications, we de- veloped a seamless flow mobility management architecture based on vehicular network application classes with network-based mobility management. Our goal is to minimize the time of flow connection exchange in order to comply with the minimum requirements of vehicular application classes, as well as to maximize their throughput. NS3 simulations were performed to analyse the behaviour of our architecture by comparing it with other three scenarios. As a result of this work, we observed that the proposed architecture presented a low handover time, with lower packet loss and lower delay.; Comment: 10 pages; 21 Figures; Journal of Communication and Networks -special issues - http://jcn.or.kr/

Network Parameters Impact on Dynamic Transmission Power Control in Vehicular Ad hoc Networks

Khan, Muhammad Imran
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/10/2013 Português
Relevância na Pesquisa
38.27278%
In vehicular ad hoc networks, the dynamic change in transmission power is very effective to increase the throughput of the wireless vehicular network and decrease the delay of the message communication between vehicular nodes on the highway. Transmission range is directly proportional to the transmission power the moving node. If the transmission power will be high, the interference increases that can cause higher delay in message reception at receiver end, hence the performance of the network decreased. In this paper, it is analyzed that how transmission power can be controlled by considering other different parameter of the network such as; density, distance between moving nodes, different types of messages dissemination with their priority, selection of an antenna also affects on the transmission power. The dynamic control of transmission power in VANETs serves also for the optimization of the resources where it needs, can be decreased and increased depending on the circumstances of the network. Different applications and events of different types also cause changes in transmission power to enhance the reach-ability. The analysis in this paper is comprised of density, distance with single hop and multi-hop message broadcasting based dynamic transmission power control as well as antenna selection and applications based. Some summarized tables are produced according to the respective parameters of the vehicular network. At the end some valuable observations are made and discussed in detail. This paper concludes with a grand summary of all the protocols discussed in it.; Comment: 22 pages...

Coalition Formation Games for Distributed Cooperation Among Roadside Units in Vehicular Networks

Saad, Walid; Han, Zhu; Hjørungnes, Are; Niyato, Dusit; Hossain, Ekram
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/10/2010 Português
Relevância na Pesquisa
38.18858%
Vehicle-to-roadside (V2R) communications enable vehicular networks to support a wide range of applications for enhancing the efficiency of road transportation. While existing work focused on non-cooperative techniques for V2R communications between vehicles and roadside units (RSUs), this paper investigates novel cooperative strategies among the RSUs in a vehicular network. We propose a scheme whereby, through cooperation, the RSUs in a vehicular network can coordinate the classes of data being transmitted through V2R communications links to the vehicles. This scheme improves the diversity of the information circulating in the network while exploiting the underlying content-sharing vehicle-to-vehicle communication network. We model the problem as a coalition formation game with transferable utility and we propose an algorithm for forming coalitions among the RSUs. For coalition formation, each RSU can take an individual decision to join or leave a coalition, depending on its utility which accounts for the generated revenues and the costs for coalition coordination. We show that the RSUs can self-organize into a Nash-stable partition and adapt this partition to environmental changes. Simulation results show that, depending on different scenarios...

Infocast: A New Paradigm for Collaborative Content Distribution from Roadside Units to Vehicular Networks Using Rateless Codes

Sardari, Mohsen; Hendessi, Faramarz; Fekri, Faramarz
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/01/2010 Português
Relevância na Pesquisa
37.988538%
In this paper, we address the problem of distributing a large amount of bulk data to a sparse vehicular network from roadside infostations, using efficient vehicle-to-vehicle collaboration. Due to the highly dynamic nature of the underlying vehicular network topology, we depart from architectures requiring centralized coordination, reliable MAC scheduling, or global network state knowledge, and instead adopt a distributed paradigm with simple protocols. In other words, we investigate the problem of reliable dissemination from multiple sources when each node in the network shares a limited amount of its resources for cooperating with others. By using \emph{rateless} coding at the Road Side Unit (RSU) and using vehicles as data carriers, we describe an efficient way to achieve reliable dissemination to all nodes (even disconnected clusters in the network). In the nutshell, we explore vehicles as mobile storage devices. We then develop a method to keep the density of the rateless codes packets as a function of distance from the RSU at the desired level set for the target decoding distance. We investigate various tradeoffs involving buffer size, maximum capacity, and the mobility parameter of the vehicles.

Opportunistic Routing for the Vehicular Energy Network

Lam, Albert Y. S.; Li, Victor O. K.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/12/2014 Português
Relevância na Pesquisa
38.116409%
Vehicular energy network (VEN) is a vehicular network which can transport energy over a large geographical area by means of electric vehicles (EVs). In the near future, an abundance of EVs, plentiful generation of the renewables, and mature wireless energy transfer and vehicular communication technologies will expedite the realization of VEN. To transmit energy from a source to a destination, we need to establish energy paths, which are composed of segments of vehicular routes, while satisfying various design objectives. In this paper, we develop a method to construct all energy paths for a particular energy source-destination pair, followed by some analytical results of the method. We describe how to utilize the energy paths to develop optimization models for different design goals and propose two solutions. We also develop a heuristic for the power loss minimization problem. We compare the performance of the three solution methods with artificial and real-world traffic networks and provide a comprehensive comparison in terms of solution quality, computation time, solvable problem size, and applicability. This paper lays the foundations of VEN routing.; Comment: 13 pages