Transmissão oportunística de informação em redes veiculares
Autor(a) principal: | |
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Data de Publicação: | 2013 |
Tipo de documento: | Dissertação |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10773/12741 |
Resumo: | The area of wireless communications has been the subject of several research projects over the last years. The persistent need to ”communicate” in various environments, including high mobility, make the use of wirelessbased communications a strong requirement. In this context, VANETs were created, which are networks based on Ad Hoc concept allowing the communication between vehicles and between vehicles and fixed infrastructures, that increase network’s connectivity. VANETs, due to their characteristics, introduce challenges such as shorts connectivity intervals in sparse networks, and also in situations where connectivity can be down for long periods of time. The work of this Dissertation aims to send non-urgent information in a opportunistic way, maximizing the network resources. The DTN’s concept is thus addressed as a solution to the previous described challenges. Two DTN implementations are studied and tested to be incorporated in WAVE devices communicating using the standard IEEE 802.11p for vehicular networks. After several tests, IBR-DTN proved to be the most robust and ”light” implementation to be used in embedded systems, such as the OBUs used in VANETs. Several implementation problems were detected, through several tests, and corrected to be possible to provide the functional integration of IBR-DTN in a real vehicular environment. The set of tests consisted in: two scenarios in the laboratory environment, to better understand IBR-DTN’s operation; and three scenarios in a real testbed with vehicles and fixed stations. The two scenarios tested in laboratory allowed to conclude the good performance of fragmentation process for different connection time intervals and different file sizes, where the connections between the nodes were periodically interrupted. The scenarios performed on the real testbed show that IBR-DTN operates without problems for various velocities using fixed infrastructures and a car, and two cars moving towards each other in different ways. It can be also concluded that, increasing the velocity, the contact time between nodes decreases, contributing to a larger number of fragments needed to send a specific file. The results show also that IBR-DTN has a good response in high mobility environments like VANETs. |
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Transmissão oportunística de informação em redes veicularesEngenharia electrónicaComunicações móveisVeículosThe area of wireless communications has been the subject of several research projects over the last years. The persistent need to ”communicate” in various environments, including high mobility, make the use of wirelessbased communications a strong requirement. In this context, VANETs were created, which are networks based on Ad Hoc concept allowing the communication between vehicles and between vehicles and fixed infrastructures, that increase network’s connectivity. VANETs, due to their characteristics, introduce challenges such as shorts connectivity intervals in sparse networks, and also in situations where connectivity can be down for long periods of time. The work of this Dissertation aims to send non-urgent information in a opportunistic way, maximizing the network resources. The DTN’s concept is thus addressed as a solution to the previous described challenges. Two DTN implementations are studied and tested to be incorporated in WAVE devices communicating using the standard IEEE 802.11p for vehicular networks. After several tests, IBR-DTN proved to be the most robust and ”light” implementation to be used in embedded systems, such as the OBUs used in VANETs. Several implementation problems were detected, through several tests, and corrected to be possible to provide the functional integration of IBR-DTN in a real vehicular environment. The set of tests consisted in: two scenarios in the laboratory environment, to better understand IBR-DTN’s operation; and three scenarios in a real testbed with vehicles and fixed stations. The two scenarios tested in laboratory allowed to conclude the good performance of fragmentation process for different connection time intervals and different file sizes, where the connections between the nodes were periodically interrupted. The scenarios performed on the real testbed show that IBR-DTN operates without problems for various velocities using fixed infrastructures and a car, and two cars moving towards each other in different ways. It can be also concluded that, increasing the velocity, the contact time between nodes decreases, contributing to a larger number of fragments needed to send a specific file. The results show also that IBR-DTN has a good response in high mobility environments like VANETs.A área de comunicações sem fios tem sido alvo de vários projectos de investigação ao longo dos últimos anos. A constante necessidade de ”comunicar” nos mais diversos ambientes, incluindo os de alta mobilidade, requerem comunicações sem fios. Neste contexto foram criadas as Vehicular Ad hoc Networks (VANETs), que são redes baseadas no conceito Ad Hoc, permitindo a comunicação entre veículos e entre veículos e infraestruturas fixas, que aumentam a conectividade da rede. As VANETs, devido às suas carecterísticas, apresentam desafios, tais como intervalos curtos de conectividade em cen´arios onde a densidade de nós é reduzida, e também situações onde não existe comunicação durante longos períodos de tempo. O trabalho da presente dissertação tem como objectivo possibilitar o envio de informação não urgente de forma oportunística, rentabilizando todos os recursos da rede. O conceito de Delay/Disrupt Tolerant Network (DTN) é deste modo abordado como solução para os desafios descritos anteriormente. Desta forma, duas implementações de DTN são estudadas e testadas para serem incorporadas em dispositivos Wireless Access in Vehicular Environments (WAVE), comunicando através da norma IEEE 802.11p para redes veiculares. Depois de vários testes realizados, o IBR-DTN mostrou ser a implementação mais robusta e mais ”leve” para ser utilizada em sistemas embutidos, como é o caso das On-Board Units (OBUs) utilizadas nas VANETs. Vários problemas de implementação foram detectados e corrigidos para ser possível integrar o IBR-DTN de forma funcional num ambiente veicular real. O conjunto de testes realizados consistiu em: dois cenários em laboratório para melhor perceber o funcionamento do IBR-DTN; e três cenários numa testbed real com veículos e estações fixas. Os dois cenários testados em laboratório permitem concluir o bom funcionamento do processo de fragmentação para diferentes tempos de ligação e diferentes tamanhos de ficheiros, onde as ligações entre os nós eram interrompidas periodicamente. Os cenários testados na testbed real mostram que o IBR-DTN funciona sem problemas usando várias velocidades com estações fixas e um carro, e com dois carros dirigindo-se em sentido contrário um ao outro. Permitem também concluir que, aumentando a velocidade, diminui o tempo de contacto entre os nós traduzindo-se num maior número de fragmentos para enviar um determinado ficheiro. Os resultados mostram também que o IBR-DTN tem uma boa resposta em ambientes de alta mobilidade como as VANETs.Universidade de Aveiro2014-10-30T17:31:45Z2013-01-01T00:00:00Z2013info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfhttp://hdl.handle.net/10773/12741TID:201567997engTavares, Bruno Miguel Pinhoinfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2024-02-22T11:23:15Zoai:ria.ua.pt:10773/12741Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-20T02:48:50.749252Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Transmissão oportunística de informação em redes veiculares |
title |
Transmissão oportunística de informação em redes veiculares |
spellingShingle |
Transmissão oportunística de informação em redes veiculares Tavares, Bruno Miguel Pinho Engenharia electrónica Comunicações móveis Veículos |
title_short |
Transmissão oportunística de informação em redes veiculares |
title_full |
Transmissão oportunística de informação em redes veiculares |
title_fullStr |
Transmissão oportunística de informação em redes veiculares |
title_full_unstemmed |
Transmissão oportunística de informação em redes veiculares |
title_sort |
Transmissão oportunística de informação em redes veiculares |
author |
Tavares, Bruno Miguel Pinho |
author_facet |
Tavares, Bruno Miguel Pinho |
author_role |
author |
dc.contributor.author.fl_str_mv |
Tavares, Bruno Miguel Pinho |
dc.subject.por.fl_str_mv |
Engenharia electrónica Comunicações móveis Veículos |
topic |
Engenharia electrónica Comunicações móveis Veículos |
description |
The area of wireless communications has been the subject of several research projects over the last years. The persistent need to ”communicate” in various environments, including high mobility, make the use of wirelessbased communications a strong requirement. In this context, VANETs were created, which are networks based on Ad Hoc concept allowing the communication between vehicles and between vehicles and fixed infrastructures, that increase network’s connectivity. VANETs, due to their characteristics, introduce challenges such as shorts connectivity intervals in sparse networks, and also in situations where connectivity can be down for long periods of time. The work of this Dissertation aims to send non-urgent information in a opportunistic way, maximizing the network resources. The DTN’s concept is thus addressed as a solution to the previous described challenges. Two DTN implementations are studied and tested to be incorporated in WAVE devices communicating using the standard IEEE 802.11p for vehicular networks. After several tests, IBR-DTN proved to be the most robust and ”light” implementation to be used in embedded systems, such as the OBUs used in VANETs. Several implementation problems were detected, through several tests, and corrected to be possible to provide the functional integration of IBR-DTN in a real vehicular environment. The set of tests consisted in: two scenarios in the laboratory environment, to better understand IBR-DTN’s operation; and three scenarios in a real testbed with vehicles and fixed stations. The two scenarios tested in laboratory allowed to conclude the good performance of fragmentation process for different connection time intervals and different file sizes, where the connections between the nodes were periodically interrupted. The scenarios performed on the real testbed show that IBR-DTN operates without problems for various velocities using fixed infrastructures and a car, and two cars moving towards each other in different ways. It can be also concluded that, increasing the velocity, the contact time between nodes decreases, contributing to a larger number of fragments needed to send a specific file. The results show also that IBR-DTN has a good response in high mobility environments like VANETs. |
publishDate |
2013 |
dc.date.none.fl_str_mv |
2013-01-01T00:00:00Z 2013 2014-10-30T17:31:45Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10773/12741 TID:201567997 |
url |
http://hdl.handle.net/10773/12741 |
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TID:201567997 |
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eng |
language |
eng |
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info:eu-repo/semantics/openAccess |
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openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Universidade de Aveiro |
publisher.none.fl_str_mv |
Universidade de Aveiro |
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reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
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RCAAP |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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