Solutions for vehicular communications: a review

Vehicular networks experience a number of unique challenges due to the high mobility of vehicles and highly dynamic network topology, short contact durations, disruption intermittent connectivity, significant loss rates, node density, and frequent network fragmentation. All these issues have a profound impact on routing strategies in these networks. This paper gives an insight about available solutions on related literature for vehicular communications. It overviews and compares the most relevant approaches for data communication in these networks, discussing their influence on routing strategies. It intends to stimulate research and contribute to further advances in this rapidly evolving area where many key open issues that still remain to be addressed are identified.Part of this work has been supported by the Instituto de Telecomunicações, Next Generation Networks and Applications Group (NetGNA), Portugal, in the framework of the Project VDTN@Lab, and by the Euro-NF Network of Excellence of the Seventh Framework Programme of EU, in the framework of the Specific Joint Research Project VDTN

VDTNsim: a simulation tool for vehicular delay-tolerant networks

“Copyright © [2010] IEEE. Reprinted from 15th IEEE International Workshop on Computer-Aided Modeling Analysis and Design of Communication Links and Networks.(IEEE CAMAD 2010) ISBN:978-1-4244-7634-3. This material is posted here with permission of the IEEE. Internal or personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution must be obtained from the IEEE by writing to [email protected]. By choosing to view this document, you agree to all provisions of the copyright laws protecting it.”Developing an adequate network architecture for supporting data communications in vehicular networks is critical to overcome the challenges caused by highly dynamic network topology, connectivity disruption, and intermittent connectivity issues. Among several approaches available in the literature proposed to address these problems, vehicular delay-tolerant networking (VDTN) architecture appears as a recent and innovative solution that integrates the concepts of end-to-end, asynchronous, and variable-length bundle oriented communication; Internet protocol over VDTN; and out-of-band signaling. VDTN architecture, protocols and services are in a fairly early stage of development. Therefore, simulation appears as an important tool providing a highly flexible, low-cost, and fast answer for research questions, and furnishes important inputs for exploring through prototyping. This paper presents and describes the proposal and construction of a simulation tool for VDTN networks, called VDTNsim.Part of this work has been supported by Instituto de Telecomunicações, Next Generation Networks and Applications Group (NetGNA), Portugal, in the framework of the Project VDTN@Lab, and by the Euro-NF Network of Excellence of the Seventh Framework Programme of EU, in the framework of the Specific Joint Research Project VDTN

Impact of content storage and retrieval mechanisms on the performance of vehicular delay-tolerant networks

“Copyright © [2010] IEEE. Reprinted from 18th International Conference on Software, Telecommunications and Computer Networks (SoftCOM 2010). ISBN: 978-1-4244-8663-2 . This material is posted here with permission of the IEEE. Internal or personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution must be obtained from the IEEE by writing to [email protected]. By choosing to view this document, you agree to all provisions of the copyright laws protecting it.”Vehicular Delay-Tolerant Networking (VDTN) is a new disruptive network architecture based on the concept of delay tolerant networks (DTNs). VDTNs handle non-real time applications using vehicles to carry messages on their buffers, relaying them only when a proper contact opportunity occurs. Therefore, the network performance is directly affected by the storage capacity and message retrieving of intermediate nodes. This paper proposes a suitable content storage and retrieval (CSR) mechanism for VDTN networks. This CSR solution adds additional information on control labels of the setup message associated to the corresponding data bundle (aggregated traffic) that defines and applies caching and forwarding restrictions on network traffic (data bundles). Furthermore, this work presents a performance analysis and evaluation of CSR mechanisms over a VDTN application scenario, using a VDTN testbed. This work presents the comparison of the network behavior and performance using two DTN routing protocols, Epidemic and Spray and Wait, with and without CSR mechanisms. The results show that CSR mechanisms improve the performance of VDTN networks significantly.Part of this work has been supported by the Instituto de Telecomunicações, Next Generation Networks and Applications Group (NetGNA), Portugal in the framework of the Project VDTN@Lab, and by the Euro-NF Network of Excellence from the Seventh Framework Programme of EU, in the framework of the Specific Joint Research Project VDTN

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

Performance Assessment of Aggregation and Deaggregation Algorithms in Vehicular Delay-Tolerant Networks

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, bundleoriented communication from the DTN architecture, employing a store-carryand- forward routing paradigm. In this sense, VDTNs should use the tight network resources optimizing each opportunistic contact among nodes. At the ingress edge nodes, incoming IP Packets (datagrams) are assembled into large data packets, called bundles. The bundle aggregation process plays an important role on the performance of VDTN applications. Then, this paper presents three aggregation algorithms based on time, bundle size, and a hybrid solution with combination of both. Furthermore, the following four aggregation schemes with quality of service (QoS) support are proposed: 1) single-class bundle with N = M, 2) composite-class bundle with N = M, 3) single-class bundle with N > M, and 4) composite-class bundle with N > M, where N is the number of classes of incoming packets and M is the number of priorities supported by the VDTN core network. The proposed mechanisms were evaluated through a laboratory testbed, called VDTN@Lab. The adaptive hybrid approach and the composite-class schemes present the best performance for different types of traffic load and best priorities distribution, respectively

Construction of a real vehicular delay-tolerant network testbed

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, although notable interference as fading and characteristics of the radio channel, require the use of more modern, appropriate and robust technologies. Thus, the real deployment of VDTNs confirms that VDTNs can be seen as a very promising technology for vehicular communications.Fundação para a Ciência e a Tecnologia (FCT

Towards Intelligent Caching and Retrieval Mechanisms for Upcoming Proposals on Vehicular Delay-Tolerant Networks

Vehicular delay-tolerant networks (VDTNs) are opportunistic networks that enable connectivity in challenged scenarios with unstable links where end-to-end communications may not exist. VDTN architecture handles non-real timeapplications using vehicles to relay messages between network nodes. To address the problem of intermittent connectivity, network nodes store messages on their buffers, carrying them through the network while waiting for transfer opportunities. The storage capacity of the nodes affects directly the network performance. Therefore, it is important to incorporate suitable network protocols using self-contained messages to improve communication that supports store-carry-and-forward operation procedures. Clearly, such procedures motivate content cachingand retrieval. This paper surveys the state-of-the art on intelligent caching and retrieval mechanisms focusing on ad-hoc and delay tolerant networks (DTN). These approaches can offer important insights for upcoming proposals on intelligent caching and retrieval mechanisms for VDTNs

車両・無人航空機を活用した災害時情報共有のためのDTNプロトコル

電気通信大学202

Congressos amb més articles Campus del Baix Llobregat (CBL) - 2011

Es presenta la llista de congressos en les que més han participat els autors del CBL ordenat per centres. Si el centre no apareix vol dir que els congressos en el que han participat els seus autors no están buidats a l’SCOPUS.Preprin