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“Copyright © [2009] IEEE. Reprinted from Next Generation Internet Network. NGI '09). ISBN:978-1-4244-4244-7. 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 pubs-permissions@ieee.org. By choosing to view this document, you agree to all provisions of the copyright laws protecting it.”
Vehicular Delay-Tolerant Networking (VDTN) is a Delay-Tolerant Network (DTN) based architecture concept for transit networks, where vehicles movement and their bundle relaying service is opportunistically exploited to enable non-real time applications, under environments prone to connectivity disruptions, network partitions and potentially long delays. In VDTNs, network resources may be limited, for instance due to physical constraints of the network nodes. In order to be able to prioritize applications traffic according to its requirements in such constrained scenarios, traffic differentiation mechanisms must be introduced at the VDTN architecture. This work considers a priority classes of service (CoS) model and investigates how different buffer management strategies can be combined with drop and scheduling policies, to provide strict priority based services, or to provide custom allocation of network resources. The efficiency and tradeoffs of these proposals is evaluated through extensive simulation.
Vehicular Delay-Tolerant Network (VDTN) appears as a particular application of the Delay-Tolerant Network (DTN) concept to transit networks. In this paper we analyze the use of a VDTN to provide asynchronous Internet access on a rural remote region scenario. Through simulation we evaluate the impact of a shortest path based movement model on the performance of four DTN routing protocols in respect to message delivery probability and message average delay.
“Copyright © [2009] IEEE. Reprinted from 17th International Conference on Software, Telecommunications & Computer Networks, 2009. SoftCOM 2009.ISBN:978-1-4244-4973-6. 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 pubs-permissions@ieee.org. By choosing to view this document, you agree to all provisions of the copyright laws protecting it.”
“Copyright © [2009] IEEE. Reprinted from Second International Conference on Communication Theory Reliability, and Quality of Service, 2009. CTRQ'09. ISBN:978-1-4244-4423-6. 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 pubs-permissions@ieee.org. By choosing to view this document, you agree to all provisions of the copyright laws protecting it.”
“Copyright © [2009] IEEE. Reprinted from Fourteenth IEEE Symposium on Computers and Communications (ISCC’09.ISSN:1530-1346. 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 pubs-permissions@ieee.org. By choosing to view this document, you agree to all provisions of the copyright laws protecting it.”
Vehicular Delay-Tolerant Networking (VDTN) was proposed as a new variant of a delay/disruptive-tolerant network, designed for vehicular networks. These networks are subject to several limitations including short contact durations, connectivity disruptions, network partitions, intermittent connectivity, and long delays. To address these connectivity issues, an asynchronous, store-carry-and-forward paradigm is combined with opportunistic bundle replication, to achieve multi-hop data delivery. Since VDTN networks are resource-constrained, for example in terms of communication bandwidth and storage capacity, a key challenge is to provide scheduling and dropping policies that can improve the overall performance of the network. This paper investigates the efficiency and tradeoffs of several scheduling and dropping policies enforced in a Spray and Wait routing scheme. It has been observed that these policies should give preferential treatment to less replicated bundles for a better network performance in terms of delivery ratio and average delivery delay.
Vehicular delay-tolerant networks (VDTNs) appear as an alternative to provide low cost asynchronous internet access on developing countries or isolated regions, enabling non-real time services, such as e-mail, web access, telemedicine, environmental monitoring and other data collection applications. VDTNs are based on the delay-tolerant network (DTN) concept applied to vehicular networks, where vehicles mobility is used for connectivity.
This paper considers a rural connectivity scenario and investigates how different mobility patterns and vehicle densities influence the performance of DTN routing protocols applied to VDTN networks. Moreover, routing protocols parameters are also changed in the present study. We analyse their effect on the performance of VDTNs through the bundle delivery ratio and the bundle average delay.
We expect that this contribution will provide a deep understanding about implications of movement models on the performance of VDTNs applied to rural scenarios, leading to insights for future routing algorithm theoretic study and protocol design.
Based on the concepts of Delay-Tolerant Network (DTN) and Opportunistic Networks, Vehicular opportunistic networks have been proposed to interconnect developing communities, or to implement disaster recovery networks when all other networks fail. Other possible application scenarios for these networks include traffic monitoring, accident warnings, advertisements, and information retrieval applications. The diversity of these network environments introduces challenging issues related to the architecture, protocol designs, interoperability, security, management, and stability of vehicular opportunistic networks. Furthermore, these networks are characterized by variable and intermittent connectivity and frequent network partition. The store-carry-and forward strategy can be used to cope with disconnections. However, in sparse networks with low node density, this strategy may be complemented with the introduction of stationary relay nodes into the network. These nodes are placed along vehicle's routes and create additional transmission opportunities. Therefore, when correctly positioned they will contribute to augment the message delivery ratio. This chapter investigates recent advances related to the deployment of stationary relay nodes on vehicular opportunistic networks. Furthermore, it presents a study that evaluates the impact of adding stationary relay nodes on the performance of DTN routing protocols applied to vehicular opportunistic networks. Two distinct environments were considered, rural and urban scenarios. Each of them combines different application scenarios, map areas, node density, and vehicle movement models. For both scenarios, results show that stationary relay nodes increase the number of contacts between network nodes, improving the overall performance of the network in terms of message delivery ratio.
“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 pubs-permissions@ieee.org. By choosing to view this document, you agree to all provisions of the copyright laws protecting it.”
“Copyright © [2010] IEEE. Reprinted from IEEE International Conference on Communications (IEEE ICC 2010) - General Symposium on Selected Areas in Communications (ICC'10 SAS).ISSN:1550-3607. 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 pubs-permissions@ieee.org. By choosing to view this document, you agree to all provisions of the copyright laws protecting it.”
“Copyright © [2010] IEEE. Reprinted from IEEE International Conference on Communications (IEEE ICC 2010). ISSN:1550-3607. 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 pubs permissions@ieee.org. By choosing to view this document, you agree to all provisions of the copyright laws protecting it.”
BOLETIM DA PROPRIEDADE INDUSTRIAL
No 2010/10/27 (208/2010) 27 de OUTUBRO de 2010
