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

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

Video Streaming over Vehicular Ad Hoc Networks: A Comparative Study and Future Perspectives

Vehicular  Ad Hoc Network  (VANET) is emerged as an important research area that provides ubiquitous short-range connectivity among moving vehicles.  This network enables efficient traffic safety and infotainment applications. One of the promising applications is video transmission in vehicle-to-vehicle or vehicle-to-infrastructure environments.  But, video streaming over vehicular environment is a daunting task due to high movement of vehicles. This paper presents a survey on state-of-arts of video streaming over VANET. Furthermore, taxonomy of vehicular video transmission is highlighted in this paper with special focus on significant applications and their requirements with challenges, video content sharing, multi-source video streaming and video broadcast services. The comparative study of the paper compares the video streaming schemes based on type of error resilient technique, objective of study, summary of their study, the utilized simulator and the type of video sharing.  Lastly, we discussed the open issues and research directions related to video communication over VANET

Performance Assessment of Fragmentation Mechanisms for Vehicular Delay-Tolerant Networks

[EN] Vehicular Delay-Tolerant Networks (VDTNs) are a new approach for vehicular communications where vehicles cooperate with each other, acting as the communication infrastructure, to provide low-cost asynchronous opportunistic communications. These communication technologies assume variable delays and bandwidth constraints characterized by a non-transmission control protocol/internet protocol architecture but interacting with it at the edge of the network. VDTNs are based on the principle of asynchronous communications, bundle-oriented communication from the DTN architecture, employing a store-carry-and-forward routing paradigm. In this sense, VDTNs should use the tight network resources optimizing each opportunistic contact among nodes. Given the limited contact times among nodes, fragmentation appears as a possible solution to improve the overall network performance, increasing the bundle delivery probability. This article proposes the use of several fragmentation approaches (proactive, source, reactive, and toilet paper) for VDTNs. They are discussed and evaluated through a laboratory testbed. Reactive and toilet paper approaches present the best results. It was also shown that only the source fragmentation approach presents worst results when compared with non-fragmentation approaches.This study was partially supported by the Instituto de Telecomunicacoes, Next Generation Networks and Applications Group (NetGNA), Portugal, by the Euro-NF Network of Excellence of the Seventh Framework Programme of EU, in the framework of the Specific Joint Research Project VDTN, and by the INESC-ID multiannual funding through the PIDDAC program funds and National Funding from the FCT - Fundacao para a Ciencia e a Tecnologia through the PEst-OE/EEI/LA0008/2011 and PTDC/EEA-TEL/099074/2008 (MPSat) Projects.Dias, JAFF.; Rodrigues, JJPC.; Isento, JN.; Pereira, PRBA.; Lloret, J. (2011). Performance Assessment of Fragmentation Mechanisms for Vehicular Delay-Tolerant Networks. EURASIP Journal on Wireless Communications and Networking. 2011(195):1-14. https://doi.org/10.1186/1687-1499-2011-195S1142011195Tatchikou R, Biswas S, Dion F: Cooperative vehicle collision avoidance using inter-vehicle packet forwarding. In Presented at the IEEE Global Telecommunications Conference (IEEE GLOBECOM 2005). St. Louis, MO, USA; 2005.Park JS, Lee U, Oh SY, Gerla M, Lun DS: Emergency related video streaming in VANET using network coding. In The Third ACM International Workshop on Vehicular Ad Hoc Networks. (VANET 2006), Los Angeles, CA, USA; 2006:102-103.Buchenscheit A, Schaub F, Kargl F, Weber M: A VANET-based emergency vehicle warning system. Presented at the First IEEE Vehicular Networking Conference (IEEE VNC 2009), Tokyo, Japan 2009.Nekovee M: Sensor networks on the road: the promises and challenges of vehicular ad hoc networks and vehicular grids. In Proceedings of the Workshop on Ubiquitous Computing and e-Research. Edinburgh, UK; 2005.Blum J, Eskandarian A, Hoffmman L: Challenges of intervehicle ad hoc networks. IEEE Trans. Intell. Transport. Syst 2004, 5(4):347-351. 10.1109/TITS.2004.838218Yousefi S, Mousavi MS, Fathy M: Vehicular ad hoc networks (VANETs): challenges and perspectives. 6th International Conference on ITS Telecommunications (ITST 2006) 2006, 761-766.Füßler H, Torrent-Moreno M, Transier M, Festag A, Hartenstein H: Thoughts on a protocol architecture for vehicular ad-hoc networks. In Presented at the 2nd International Workshop on Intelligent Transportation (WIT 2005). Hamburg, Germany; 2005.Cerf V, Burleigh S, Hooke A, Torgerson L, Durst R, Scott K, Fall K, Weiss H: Delay-tolerant networking architecture. RFC 4838 2007. [Online] [ http://www.rfc-editor.org/rfc/rfc4838.txt ]Soares VNGJ, Farahmand F, Rodrigues JJPC: A layered architecture for vehicular delay-tolerant networks. In The Fourteenth IEEE Symposium on Computers and Communications (ISCC 2009). Sousse, Tunisia; 2009:122-127.Rodrigues JJPC, Soares VNGJ, Farahmand F: Stationary relay nodes deployment on vehicular opportunistic networks. In Mobile Opportunistic Networks: Architectures, Protocols and Applications. Edited by: Denko M. CRC Press, Taylor & Francis Group (hardcover); 2011:227-243.Postel J: Internet Protocol. RFC 791 1981. [Online] [ http://www.ietf.org/rfc/rfc791.txt ]Kent CA, Moguk JC: Fragmentation considered harmful. SIGCOMM Comput Commun Rev 1995, 25(1):75-87. 10.1145/205447.205456Kim B-S, Fang Y, Wong TF, Kwon Y: Throughput enhancement through dynamic fragmentation in wireless LANs. IEEE Trans Veh Technol 2005, 54(4):1415-1425. 10.1109/TVT.2005.851361Ginzboorg P, Niemi V, Ott J: Message Fragmentation in Disruptive Networks. Nokia Research Center, Technical Report; 2009.Legner M: Map-Based Geographic Forwarding in Vehicular Networks. Department of Informatic, University of Stuttgart; 2002.Li Q, Rus D: Sending messages to mobile users in disconnected ad-hoc wireless networks. 6th Annual International Conference on Mobile Computing and Networking, New York, USA 2000, 44-55.Vahdat A, Becker B: Epidemic Routing for Partially-Connected Ad-Hoc Networks. Duke University, Technical Report; 2000.Briesemeister L, Hommel G: Overcoming fragmentation in mobile ad-hoc networks. J Commun Netw 2000, 2(3):182-187.Liu H, Sheng H, Lv Z, Li L, Ma C: A cross layer design of fragmentation and priority scheduling in vehicular ad hoc networks. 7th World Congress on Intelligent Control and Automation (WCICA 2008) 2008, 6157-6160.Joshi HP: Distributed robust geocast: a multicast protocol for inter-vehicle communication. Master Thesis, North Carolina State University; 2006.Bachir A, Benslimane A: A multicast protocol in ad hoc networks: Inter-vehicles geocast. Proceedings of the 57th IEEE Vehicular Technology Conference, Korea 2003, 2456-2460.Mikko P, Ari K, Ott J: Message fragmentation in opportunistic DTNs. In 9th IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks (WOWMOM 2008). Newport Beach, CA, USA; 2008.Farrell S, Symington S, Weiss H: Delay-tolerant networking security overview. Internet Draft 2009. [Online] [ http://tools.ietf.org/html/draft-irtf-dtnrg-sec-overview-06 ]Magaia N, Pereira PR, Casaca A, Rodrigues J, Dias JA, Isento JN, Cervelló-Pastor C, Gallego J: Bundles fragmentation in vehicular delay-tolerant networks. 7th Euro-nf conference on next generation internet, Kaiserslautern, Germany 2011.Soares V, Rodrigues J, Farahmand F, Denko M: Exploiting node localization for performance improvement of vehicular delay-tolerant networks. In IEEE International Conference on Communications (ICC 2010). Cape Town, South Africa; 2010.Rubinstein MG, Abdesselm FB, Cavalcanti SR, Campista MEM, Alves RSA, Costa LHMK, Amorim MD, Duarte OCMB: Measuring the capacity of in-car to in-car vehicular networks. IEEE Commun Mag 2009, 47(11):128-136.Spyropoulos T, Psounis K, Raghavendra C S: Spray and wait: an efficient routing scheme for intermittently connected mobile networks. In ACM SIGCOMM 2005--Workshop on Delay Tolerant Networking and Related Networks (WDTN-05). Philadelphia, PA, USA; 2005:252-259.Lindgren A, Doria A, Davies E, Grasic S: Probabilistic routing protocol for intermittently connected networks (2010). Internet Draft 2010. [Online] [ http://tools.ietf.org/html/draft-irtf-dtnrg-prophet-06 ]Teshima S, Ohta T, Kohno E, Kakuda Y: A data transfer scheme using autonomous clustering in VANETs environment. In 10th International Symposium on Autonomous Decentralized Systems (ISADS 2011). Tokyo, Japan; 2011:477-482.Psounis K: Efficient Routing for Safety Applications in Vehicular Networks. METRANS Project DTRS98-G0019, Electrical Engineering. University of Southern California, Los Angeles, USA; 2009.Li X, Shu W, Li M, Huang H, Min-You Wu: DTN routing in vehicular sensor networks. In IEEE Global Telecommunications Conference (IEEE GLOBECOM 2008). New Orleans, USA; 2008:1-5

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

Reliability and Efficiency of Vehicular Network Applications

The DSRC/WAVE initiative is forecast to enable a plethora of applications, classified in two broad types of safety and non-safety applications. In the former type, the reliability performance is of tremendous prominence while, in the latter case, the efficiency of information dissemination is the key driving factor. For safety applications, we adopt a systematic approach to analytically investigate the reliability of the communication system in a symbiotic relationship with the host system comprising a vehicular traffic system and radio propagation environment. To this aim, the¬ interference factor is identified as the central element of the symbiotic relationship. Our approach to the investigation of interference and its impacts on the communication reliability departs from previous studies by the degree of realism incorporated in the host system model. In one dimension, realistic traffic models are developed to describe the vehicular traffic behaviour. In a second dimension, a realistic radio propagation model is employed to capture the unique signal propagation aspects of the host system. We address the case of non-safety applications by proposing a generic framework as a capstone architecture for the development of new applications and the efficiency evaluation of existing ones. This framework, while being independent from networking technology, enables accurate characterization of the various information dissemination tasks that a node performs in cooperation with others. As the central element of the framework, we propose a game theoretic model to describe the interaction of meeting nodes aiming to exchange information of mutual or social interests. An adaptive mechanism is designed to enable a mobile node to measure the social significance of various information topics, which is then used by the node to prioritize the forwarding of information objects

Developing energy-aware workload offloading frameworks in mobile cloud computing

Mobile cloud computing is an emerging field of research that aims to provide a platform on which intelligent and feature-rich applications are delivered to the user at any time and at anywhere. Computation offload between mobile and cloud plays a key role in this vision and ensures that the integration between mobile and cloud is both seamless and energy-efficient. In this thesis, we develop a suite of energy-aware workload offloading frameworks to accommodate the efficient execution of mobile workflows on a mobile cloud platform. We start by looking at two energy objectives of a mobile cloud platform. While the first objective aims at minimising the overall energy cost of the platform, the second objective aims at the longevity of the platform taking into account the residual battery power of each device. We construct optimisation models for both objectives and develop two efficient algorithms to approximate the optimal solution. According to simulation results, our greedy autonomous offload (GAO) algorithm is able to efficiently produce allocation schemes that are close to optimal. Next, we look at the task allocation problem from a workflow's perspective and develop energy-aware offloading strategies for time-constrained mobile workflows. We demonstrate the effect of software and hardware characteristics have over the offload-efficiency of mobile workflows with a workflow-oriented greedy autonomous offload (WGAO) algorithm, an extension to the GAO algorithm. Thirdly, we propose a novel network I-O model to describe the bandwidth dependencies and allocation problem in mobile networks. This model lays the foundation for further objective developments such as the cost-based and adaptive bandwidth allocation schemes which we also present in this thesis. Lastly, we apply a game theoretical approach to model the non-cooperative behaviour of mobile cloud applications that reside on the same device. Mixed-strategy Nash equilibrium is derived for the offload game which further quantifies the price of anarchy of the system

VANET-enabled eco-friendly road characteristics-aware routing for vehicular traffic

There is growing awareness of the dangers of climate change caused by greenhouse gases. In the coming decades this could result in numerous disasters such as heat-waves, flooding and crop failures. A major contributor to the total amount of greenhouse gas emissions is the transport sector, particularly private vehicles. Traffic congestion involving private vehicles also causes a lot of wasted time and stress to commuters. At the same time new wireless technologies such as Vehicular Ad-Hoc Networks (VANETs) are being developed which could allow vehicles to communicate with each other. These could enable a number of innovative schemes to reduce traffic congestion and greenhouse gas emissions. 1) EcoTrec is a VANET-based system which allows vehicles to exchange messages regarding traffic congestion and road conditions, such as roughness and gradient. Each vehicle uses the messages it has received to build a model of nearby roads and the traffic on them. The EcoTrec Algorithm then recommends the most fuel efficient route for the vehicles to follow. 2) Time-Ants is a swarm based algorithm that considers not only the amount of cars in the spatial domain but also the amoumt in the time domain. This allows the system to build a model of the traffic congestion throughout the day. As traffic patterns are broadly similar for weekdays this gives us a good idea of what traffic will be like allowing us to route the vehicles more efficiently using the Time-Ants Algorithm. 3) Electric Vehicle enhanced Dedicated Bus Lanes (E-DBL) proposes allowing electric vehicles onto the bus lanes. Such an approach could allow a reduction in traffic congestion on the regular lanes without greatly impeding the buses. It would also encourage uptake of electric vehicles. 4) A comprehensive survey of issues associated with communication centred traffic management systems was carried out