Towards video streaming in IoT environments: vehicular communication perspective

Multimedia oriented Internet of Things (IoT) enables pervasive and real-time communication of video, audio and image data among devices in an immediate surroundings. Today's vehicles have the capability of supporting real time multimedia acquisition. Vehicles with high illuminating infrared cameras and customized sensors can communicate with other on-road devices using dedicated short-range communication (DSRC) and 5G enabled communication technologies. Real time incidence of both urban and highway vehicular traffic environment can be captured and transmitted using vehicle-to-vehicle and vehicle-to-infrastructure communication modes. Video streaming in vehicular IoT (VSV-IoT) environments is in growing stage with several challenges that need to be addressed ranging from limited resources in IoT devices, intermittent connection in vehicular networks, heterogeneous devices, dynamism and scalability in video encoding, bandwidth underutilization in video delivery, and attaining application-precise quality of service in video streaming. In this context, this paper presents a comprehensive review on video streaming in IoT environments focusing on vehicular communication perspective. Specifically, significance of video streaming in vehicular IoT environments is highlighted focusing on integration of vehicular communication with 5G enabled IoT technologies, and smart city oriented application areas for VSV-IoT. A taxonomy is presented for the classification of related literature on video streaming in vehicular network environments. Following the taxonomy, critical review of literature is performed focusing on major functional model, strengths and weaknesses. Metrics for video streaming in vehicular IoT environments are derived and comparatively analyzed in terms of their usage and evaluation capabilities. Open research challenges in VSV-IoT are identified as future directions of research in the area. The survey would benefit both IoT and vehicle industry practitioners and researchers, in terms of augmenting understanding of vehicular video streaming and its IoT related trends and issues

Interference-aware multipath video streaming in vehicular environments

The multipath transmission is one of the suitable transmission methods for high data rate oriented communication such as video streaming. Each video packets are split into smaller frames for parallel transmission via different paths. One path may interfere with another path due to these parallel transmissions. The multipath oriented interference is due to the route coupling which is one of the major challenges in vehicular traffic environments. The route coupling increases channel contention resulting in video packet collision. In this context, this paper proposes an Interference-aware Multipath Video Streaming (I-MVS) framework focusing on link and node disjoint optimal paths. Specifically, a multipath vehicular network model is derived. The model is utilized to develop interference-aware video streaming method considering angular driving statistics of vehicles. The quality of video streaming links is measured based on packet error rate considering non-circular transmission range oriented shadowing effects. Algorithms are developed as a complete operational I-MVS framework. The comparative performance evaluation attests the benefit of the proposed framework considering various video streaming related metrics

Reliable Multihop Broadcast Protocol with a Low-Overhead Link Quality Assessment for ITS Based on VANETs in Highway Scenarios

Vehicular ad hoc networks (VANETs) have been identified as a key technology to enable intelligent transport systems (ITS), which are aimed to radically improve the safety, comfort, and greenness of the vehicles in the road. However, in order to fully exploit VANETs potential, several issues must be addressed. Because of the high dynamic of VANETs and the impairments in the wireless channel, one key issue arising when working with VANETs is the multihop dissemination of broadcast packets for safety and infotainment applications. In this paper a reliable low-overhead multihop broadcast (RLMB) protocol is proposed to address the well-known broadcast storm problem. The proposed RLMB takes advantage of the hello messages exchanged between the vehicles and it processes such information to intelligently select a relay set and reduce the redundant broadcast. Additionally, to reduce the hello messages rate dependency, RLMB uses a point-to-zone link evaluation approach. RLMB performance is compared with one of the leading multihop broadcast protocols existing to date. Performance metrics show that our RLMB solution outperforms the leading protocol in terms of important metrics such as packet dissemination ratio, overhead, and delay

Named Data Networking in Vehicular Ad hoc Networks: State-of-the-Art and Challenges

International audienceInformation-Centric Networking (ICN) has been proposed as one of the future Internet architectures. It is poised to address the challenges faced by today's Internet that include, but not limited to, scalability, addressing, security, and privacy. Furthermore, it also aims at meeting the requirements for new emerging Internet applications. To realize ICN, Named Data Networking (NDN) is one of the recent implementations of ICN that provides a suitable communication approach due to its clean slate design and simple communication model. There are a plethora of applications realized through ICN in different domains where data is the focal point of communication. One such domain is Intelligent Transportation System (ITS) realized through Vehicular Ad hoc NETwork (VANET) where vehicles exchange information and content with each other and with the infrastructure. To date, excellent research results have been yielded in the VANET domain aiming at safe, reliable, and infotainment-rich driving experience. However, due to the dynamic topologies, host-centric model, and ephemeral nature of vehicular communication, various challenges are faced by VANET that hinder the realization of successful vehicular networks and adversely affect the data dissemination, content delivery, and user experiences. To fill these gaps, NDN has been extensively used as underlying communication paradigm for VANET. Inspired by the extensive research results in NDN-based VANET, in this paper, we provide a detailed and systematic review of NDN-driven VANET. More precisely, we investigate the role of NDN in VANET and discuss the feasibility of NDN architecture in VANET environment. Subsequently, we cover in detail, NDN-based naming, routing and forwarding, caching, mobility, and security mechanism for VANET. Furthermore, we discuss the existing standards, solutions, and simulation tools used in NDN-based VANET. Finally, we also identify open challenges and issues faced by NDN-driven VANET and highlight future research directions that should be addressed by the research community

Advances in Vehicular Ad-hoc Networks (VANETs): challenges and road-map for future development

Recent advances in wireless communication technologies and auto-mobile industry have triggered a significant research interest in the field of vehicular ad-hoc networks (VANETs) over the past few years. A vehicular network consists of vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications supported by wireless access technologies such as IEEE 802.11p. This innovation in wireless communication has been envisaged to improve road safety and motor traffic efficiency in near future through the development of intelligent transportation system (ITS). Hence, governments, auto-mobile industries and academia are heavily partnering through several ongoing research projects to establish standards for VANETs. The typical set of VANET application areas, such as vehicle collision warning and traffic information dissemination have made VANET an interesting field of mobile wireless communication. This paper provides an overview on current research state, challenges, potentials of VANETs as well as the ways forward to achieving the long awaited ITS

Mobile Ad-Hoc Networks

Being infrastructure-less and without central administration control, wireless ad-hoc networking is playing a more and more important role in extending the coverage of traditional wireless infrastructure (cellular networks, wireless LAN, etc). This book includes state-of the-art techniques and solutions for wireless ad-hoc networks. It focuses on the following topics in ad-hoc networks: vehicular ad-hoc networks, security and caching, TCP in ad-hoc networks and emerging applications. It is targeted to provide network engineers and researchers with design guidelines for large scale wireless ad hoc networks

Distribuição de conteúdos em redes veiculares usando mecanismos de comunicação tolerantes ao atraso

Mestrado em Engenharia Eletrónica e TelecomunicaçõesThe last couple of decades have been the stage for the introduction of new telecommunication networks. It is expected that in the future all types of vehicles, such as cars, buses and trucks have the ability to intercommunicate and form a vehicular network. Vehicular networks display particularities when compared to other networks due to their continuous node mobility and their wide geographical dispersion, leading to a permanent network fragmentation. Therefore, the main challenges that this type of network entails relate to the intermittent connectivity and the long and variable delay in information delivery. To address the problems related to the intermittent connectivity, a new concept was introduced – Delay Tolerant Network (DTN). This architecture is built on a Store-Carry-and-Forward (SCF) mechanism in order to assure the delivery of information when there is no end-to-end path defined. Vehicular networks support a multiplicity of services, including the transportation of non-urgent information. Therefore, it is possible to conclude that the use of a DTN for the dissemination of non-urgent information is able to surpass the aforementioned challenges. The work developed focused on the use of DTNs for the dissemination of non-urgent information. This information is originated in the network service provider and should be available on mobile network terminals during a limited period of time. In order to do so, four different strategies were deployed: Random, Least Number of Hops First (LNHF), Local Rarest Bundle First (LRBF) e Local Rarest Generation First (LRGF). All of these strategies have a common goal: to disseminate content into the network in the shortest period of time and minimizing network congestion. This work also contemplates the analysis and implementation of techniques that reduce network congestion. The design, implementation and validation of the proposed strategies was divided into three stages. The first stage focused on creating a Matlab emulator for the fast implementation and strategy validation. This stage resulted in the four strategies that were afterwards implemented in the DTNs software Helix – developed in a partnership between Instituto de Telecomunicac¸˜oes (IT) and Veniam R , which are responsible for the largest operating vehicular network worldwide that is located in Oporto city. The strategies were later evaluated on an emulator that was built for the largescale testing of DTN. Both emulators account for vehicular mobility based on information previously collected from the real platform. Finally, the strategy that presented the best overall performance was tested on a real platform – in a lab environment – for concept and operability demonstration. It is possible to conclude that two of the implemented strategies (LRBF and LRGF) can be deployed in the real network and guarantee a significant delivery rate. The LRBF strategy has the best performance in terms of delivery. However, it needs to add a significant overhead to the network in order to work. In the future, tests of scalability should be conducted in a real environment in order to confirm the emulator results. The real implementation of the strategies should be accompanied by the introduction of new types of services for content distribution.Nas últimas décadas tem-se assistido à introdução de novas redes de telecomunicações. Entre estas destacam-se as redes veiculares constituídas por todo o tipo de veículos com capacidades de intercomunicação. As redes veiculares têm especificidades singulares face a outro tipo de redes devido à constante mobilidade dos nós e à sua elevada dispersão geográfica. Os principais desafios introduzidos por este tipo de redes prendem-se com a conectividade intermitente e o atraso longo e variado na entrega da informação. Por forma a fazer face aos problemas relacionados com a conectividade intermitente, introduziu-se um novo conceito intitulado de Delay Tolerant Network (DTN). Esta arquitetura assenta num mecanismo de StoreCarry-and-Forward (SCF) por forma a garantir a entrega de informação em situações onde não existe um caminho estabelecido fim-a-fim. As redes veiculares suportam uma multiplicidade de serviços, nos quais se inclui o transporte de informação não-urgente. Desta forma, a utilização de uma DTN para a difusão de informação não-urgente permite ultrapassar os desafios identificados anteriormente. O trabalho realizado foca-se na utilização de DTNs para a disseminação de informação não-urgente. Por forma a operacionalizar esta premissa foram implementadas quatro estratégias distintas: Random, Least Number of Hops First (LNHF), Local Rarest Bundle First (LRBF) e Local Rarest Generation First (LRGF). Todas estas estratégias tem um objetivo comum: disseminar um conteúdo na rede no menor tempo possível minimizando ao máximo o congestionamento da rede. Foram também implementadas e estudadas técnicas para minimizar o congestionamento do meio. A metodologia de desenho, implementação e validação das estratégias propostas foi desenvolvida em três fases. A primeira focou-se na criação de um emulador Matlab para a implementação rápida e validação das estratégias. Dessa primeira fase resultaram quatro estratégias que foram posteriormente implementadas no software de DTNs Helix desenvolvido através de uma parceria entre o Instituto de Telecomunicações (IT) e a Veniam R (responsáveis pela maior rede veicular em operação a nível mundial localizada na cidade do Porto). As estratégias foram depois avaliadas num emulador construído para fazer testes de grande escala. Ambos os emuladores introduzem a mobilidade dos veículos com base em informação recolhida previamente da plataforma real. Por fim a estratégia que apresentou o melhor desempenho foi introduzida e testada numa plataforma real para demonstração de conceito e operacionalidade. Conclui-se que duas das estratégias implementadas (LRBF and LRGF) são passíveis de utilização na rede real garantido uma taxa de entrega significativa. A estratégia LRBF apresentou o melhor desempenho em termos de entrega, no entanto, necessita de adicionar um overhead considerável na rede para funcionar. No futuro devem ser realizados testes de escalabilidade em ambiente real por forma a confirmar os resultados obtidos em ambiente de emulação e real em pequena escala. A implementação real das estratégias deve ser acompanhada pela introdução de novos tipos de serviços para distribuição de conteúdos

Distribuição de conteúdos em redes veiculares com mecanismos de filtragem

Mestrado em Engenharia Eletrónica e TelecomunicaçõeConectividade representa uma grande necessidade da população desde o início dos tempos. As pessoas têm, logo à partida, um desejo de estarem ligadas entre si e ao resto do mundo. Tal não mudou nos tempos actuais, especialmente na era das novas tecnologias onde conectarse com alguém está apenas a uns cliques de distância. Do ponto de vista de engenheiros da área das telecomunicações, este rápido desenvolvimento nas comunicações sem fios tem sido especialmente marcante. Devido a esta constante necessidade de comunicação, as VANETs (Vehicular Ad-Hoc Networks) atraem actualmente um interesse significativo. Esse interesse deve-se ao facto de as redes veiculares não só poderem ser usadas para uma condução potencialmente mais segura, como também poderem proporcionar aos passageiros o acesso à Internet. As redes veiculares têm características específicas face a outro tipo de redes, tais como o número elevado de veículos ou nós, rotas imprevis íveis e a constante perda de conectividade entre os mesmos, revelando vários desafios que propõem estudos para os solucionar. A solução encontrada para a conectividade intermitente prende-se com o uso de DTNs (Delay-Tolerant Networks) cuja arquitectura assegura a entrega de informação mesmo quando não há conhecimento do percurso completo que esta deve percorrer. Esta Dissertação de Mestrado foca-se no estudo da disseminação de conteúdo não-urgente via uso de DTNs, assegurando que esta mesma disseminação é feita no menor espaço de tempo possível e com o mínimo congestionamento possível na rede. Actualmente, embora a entrega de informação já seja efectuada na rede num espaço de tempo satisfatório, as estratégias implementadas forçam um congestionamento (overhead ) considerável na rede. Para combater este efeito, foi desenvolvida uma estratégia de disseminação através do uso de Bloom Filters, uma estrutura de dados capaz de eliminar a maior parte dos acessos desnecessários à memória, assegurando a um nó a existência de um pacote específico, com uma certa probabilidade, de entre toda a informação que os seus vizinhos contêm. Esta estratégia foi implementada no software de DTNs mOVERS Emulator, desenvolvido pelo Instituto de Telecomunicações de Aveiro (IT) e pela Veniam® e posteriormente testada no mesmo. O emulador utilizado simula uma rede veicular com base em informação recolhida da rede veicular da cidade do Porto. Após análise dos resultados obtidos, foi concluído que a nova estratégia de disseminação proposta, denominada FILTER, cumpriu o principal objectivo proposto, nomeadamente, a redução do overhead na rede veicular, com uma pequena perda de taxa de entrega da informação. Para trabalho futuro, é aconselhável realizar um estudo mais extenso em métodos relacionados com utilidade da informação para optimizar essa mesma taxa de entrega.Connectivity represents one of people's great needs since the beginning of times. From the start, people have a desire to be connected to each other and to the rest of the world. Such has not changed in modern times, especially in the era of new technologies where connecting with someone is only a few clicks away. From the point of view of engineers in the area of telecommunications, this fast development in wireless communications has been especially outstanding. Due to this constant need for communication, VANETs (Vehicular Ad- Hoc Networks) are currently attracting signi cant attention. Such attention is due to the fact that vehicular networks may be used for, not only potentially safer driving, they also provide its users with Internet access. Vehicular Networks have speci c characteristics when compared to other types of networks, such as the high number of vehicles or nodes, unpredictable routes and the constant loss of connectivity between these nodes, thus revealing several challenges which propose studies to solve them. The solution found for the intermittent connectivity involves the use of DTNs (Delay-Tolerant Networks) whose architecture ensures the delivery of information even without knowledge of the whole path it must travel. This Masters Dissertation focuses on the study of non-urgent content dissemination through the use of DTNs, ensuring that this same dissemination is done within the shortest time frame and with the minimum congestion possible in the network. Currently, though the information delivery is already performed in the network with a satisfactory time frame, the implemented strategies force considerable congestion in the network. To overcome this e ect, a dissemination strategy was developed through the use of Bloom Filters, a data structure capable of eliminating most of the unnecessary access to memory, by ensuring a node the existence of a speci c packet, with a certain probability, from among all the information its neighbours contain. This strategy was implemented in the DTN software mOVERS, developed by Instituto de Telecomunicações in Aveiro (IT) and Veniam® and posteriorly tested in the same emulator. The emulator used simulates a vehicular network with information gathered from the vehicular network in the city of Porto. After the analysis of the obtained results, it was concluded that the new proposed dissemination strategy, named FILTER, has ful lled its primary objective, namely, the reduction of the vehicular network's overhead, with a small loss in the delivery rate of the information. For future work, it is advisable to perform a more extensive study in methods related to the information's usefulness to a neighbour to optimize such delivery rate

DESIGN OF EFFICIENT IN-NETWORK DATA PROCESSING AND DISSEMINATION FOR VANETS

By providing vehicle-to-vehicle and vehicle-to-infrastructure wireless communications, vehicular ad hoc networks (VANETs), also known as the “networks on wheels”, can greatly enhance traffic safety, traffic efficiency and driving experience for intelligent transportation system (ITS). However, the unique features of VANETs, such as high mobility and uneven distribution of vehicular nodes, impose critical challenges of high efficiency and reliability for the implementation of VANETs. This dissertation is motivated by the great application potentials of VANETs in the design of efficient in-network data processing and dissemination. Considering the significance of message aggregation, data dissemination and data collection, this dissertation research targets at enhancing the traffic safety and traffic efficiency, as well as developing novel commercial applications, based on VANETs, following four aspects: 1) accurate and efficient message aggregation to detect on-road safety relevant events, 2) reliable data dissemination to reliably notify remote vehicles, 3) efficient and reliable spatial data collection from vehicular sensors, and 4) novel promising applications to exploit the commercial potentials of VANETs. Specifically, to enable cooperative detection of safety relevant events on the roads, the structure-less message aggregation (SLMA) scheme is proposed to improve communication efficiency and message accuracy. The scheme of relative position based message dissemination (RPB-MD) is proposed to reliably and efficiently disseminate messages to all intended vehicles in the zone-of-relevance in varying traffic density. Due to numerous vehicular sensor data available based on VANETs, the scheme of compressive sampling based data collection (CS-DC) is proposed to efficiently collect the spatial relevance data in a large scale, especially in the dense traffic. In addition, with novel and efficient solutions proposed for the application specific issues of data dissemination and data collection, several appealing value-added applications for VANETs are developed to exploit the commercial potentials of VANETs, namely general purpose automatic survey (GPAS), VANET-based ambient ad dissemination (VAAD) and VANET based vehicle performance monitoring and analysis (VehicleView). Thus, by improving the efficiency and reliability in in-network data processing and dissemination, including message aggregation, data dissemination and data collection, together with the development of novel promising applications, this dissertation will help push VANETs further to the stage of massive deployment