The Experts below are selected from a list of 9219 Experts worldwide ranked by ideXlab platform
Shun-ren Yang - One of the best experts on this subject based on the ideXlab platform.
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An adaptive trajectory-based group Message Delivery protocol with detour support for vehicular networks
International Journal of Ad Hoc and Ubiquitous Computing, 2020Co-Authors: Guann-long Chiou, Shun-ren YangAbstract:To realise I2V group Message Delivery, some previously proposed protocols utilise the future trajectories of vehicles to deploy Message Delivery routes. However, we have noticed that none of these protocols consider that the destination vehicles may take unexpected detours, resulting in these vehicles no longer passing the rendezvous points. Thus, the detoured vehicles miss the Messages stored on the rendezvous points. To address this issue, this paper designs tc-eTGMD, which aims to redeploy only the routes for the detour vehicles when the detour events happen. Moreover, this scheme can guarantee the reaction time and can offload the traffic while handling the detour events. The specific contributions of this paper are as follows: (1) we formally formulate the trajectory-based I2V group Message Delivery with the detour events problem; (2) we give a detailed design of tc-eTGMD protocol and (3) we conduct extensive simulation experiments to evaluate tc-eTGMD's Message Delivery performance.
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Modeling Trajectory-Based I2V Message Delivery Over VANETs with Vehicle Detours
2018 IEEE International Conference on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber Physical and , 2018Co-Authors: Shun-ren Yang, Yi-syuan ShenAbstract:Vehicular ad-hoc networking (VANET) is an effective and green approach to supporting the communication requirements of networked electric vehicles (EVs). This paper studies trajectory-based infrastructure-to-vehicle (I2V) Message Delivery over VANETs, whose operations can be summarized as follows: 1) the server first selects an appropriate roadside unit on the destination vehicle's subsequent trajectory as the rendezvous point (RP); 2) the server then transmits the Message to the RP and expects that when the vehicle passes through the RP later, the Message can be delivered from the RP to the vehicle. Such existing protocols commonly assume that vehicles move strictly following the suggested routes, without detours. Consequently, the Delivery performance can be overestimated. This paper proposes an analytic model to investigate the impacts of vehicle detours on trajectory-based VANET I2V Message Delivery. The model derives the probability that a destination vehicle will pass through its RP, and thus receive the Message successfully, considering the fact that the vehicle may detour during the movement. We validate the analytic model against simulation. Finally, several numerical examples are presented to quantitatively show how the Message reception performance is affected by vehicle detours.
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On Trajectory-Based I2V Group Message Delivery Over Vehicular Ad-Hoc Networks
IEEE Transactions on Vehicular Technology, 2016Co-Authors: Guann-long Chiou, Shun-ren YangAbstract:In the literature, future vehicle trajectories have been exploited to improve the performance of challenging infrastructure-to-vehicle (I2V) group Message Delivery over vehicular ad-hoc networks (VANETs). The existing trajectory-based I2V group Message Delivery protocols typically consist of two phases. Based on the reported vehicle trajectories, phase one identifies an appropriate rendezvous point of the group Message and each of the member vehicles. Then, phase two composes a multicast tree to deliver the Message to these selected rendezvous points. The Message is kept at the rendezvous points for later last-hop Delivery when the member vehicles pass through. However, separately handling the rendezvous point selection and the multicast tree construction may significantly restrict the overall Message Delivery performance. This paper designs a novel trajectory-based I2V group Message Delivery protocol, i.e., eTGMD, for delay-tolerant vehicular applications. eTGMD iteratively selects a promising rendezvous point and extends the current multicast tree to cover the selected rendezvous point. Our specific contributions include the following: 1) We prove the trajectory-based I2V group Message Delivery problem's NP-hardness, 2) we theoretically analyze the worst-case performance bound and time complexity of eTGMD, and 3) we conduct extensive simulation experiments to evaluate eTGMD's Message Delivery performance.
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TGMD: A trajectory-based group Message Delivery protocol for Vehicular Ad Hoc Networks
2012 IEEE International Conference on Communications (ICC), 2012Co-Authors: Wan-han Hsieh, Shun-ren Yang, Guann-long ChiouAbstract:Infrastructure-to-vehicle (I2V) group Message Delivery is a common operation required by a wide variety of vehicular ad hoc network (VANET) applications. However, due to the highly dynamic mobility in VANETs, it remains a difficult problem to deliver Messages to a group of moving vehicles scattering over the whole network. The contribution of this paper is to propose the first trajectory-based I2V group Message Delivery protocol, TGMD, that exploits vehicle trajectories to improve the group-Message Delivery performance. TGMD contains two phases. The first phase determines a few rendezvous points from which the member vehicles can receive the Message. Then the second phase transmits the group Message over multiple hops to these selected rendezvous points using a multicast-like forwarding scheme to avoid redundant packet transmissions over the overlapped road segments. TGMD aims to minimize the required number of network-layer packet transmissions under a relatively loose delay constraint. Our extensive simulation results indicate that in comparison with the trajectory-based single-destination I2V Message Delivery scheme (through N-unicasting), TGMD significantly reduces the required number of packet transmissions (and thus bandwidth consumption) while achieving a high Delivery ratio around 90%.
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ICC - TGMD: A trajectory-based group Message Delivery protocol for Vehicular Ad Hoc Networks
2012 IEEE International Conference on Communications (ICC), 2012Co-Authors: Wan-han Hsieh, Shun-ren Yang, Guann-long ChiouAbstract:Infrastructure-to-vehicle (I2V) group Message Delivery is a common operation required by a wide variety of vehicular ad hoc network (VANET) applications. However, due to the highly dynamic mobility in VANETs, it remains a difficult problem to deliver Messages to a group of moving vehicles scattering over the whole network. The contribution of this paper is to propose the first trajectory-based I2V group Message Delivery protocol, TGMD, that exploits vehicle trajectories to improve the group-Message Delivery performance. TGMD contains two phases. The first phase determines a few rendezvous points from which the member vehicles can receive the Message. Then the second phase transmits the group Message over multiple hops to these selected rendezvous points using a multicast-like forwarding scheme to avoid redundant packet transmissions over the overlapped road segments. TGMD aims to minimize the required number of network-layer packet transmissions under a relatively loose delay constraint. Our extensive simulation results indicate that in comparison with the trajectory-based single-destination I2V Message Delivery scheme (through N-unicasting), TGMD significantly reduces the required number of packet transmissions (and thus bandwidth consumption) while achieving a high Delivery ratio around 90%.
Yoonyoung Sung - One of the best experts on this subject based on the ideXlab platform.
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Light-Weight Reliable Broadcast Message Delivery for Vehicular Ad-Hoc Networks
2012 IEEE 75th Vehicular Technology Conference (VTC Spring), 2012Co-Authors: Yoonyoung SungAbstract:Reliability as well as efficiency of transmissions is of a paramount issue for the safety critical services of VANET due to the urgency and/or significance of the Messages. To this end,various retransmission mechanisms have been studied for reliable broadcast Message Delivery in VANETs. Most of the existing approaches, though, rely on periodic beacons for retransmission decisions and intrinsically require high control overheads. Especially, in urban environments where the traffic density tends to be high, minimizing control overheads is important not only for the efficiency but also for the reliability of user Message Delivery. In this paper, we propose an efficient broadcast Message Delivery mechanism, which does not rely on the periodic beacon exchanges. Based on the observation that the broadcast Message Delivery could be particularly difficult at the intersections due to the signal diffraction and attenuation caused by the obstacles such as buildings around the corners of the intersection, a novel mechanism to make efficient and effective retransmissions across an intersection is proposed. Simulation results show that the proposed mechanism can provide similar or better reliability while incurring prominently less overheads than the existing approaches.
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VTC Spring - Light-Weight Reliable Broadcast Message Delivery for Vehicular Ad-Hoc Networks
2012 IEEE 75th Vehicular Technology Conference (VTC Spring), 2012Co-Authors: Yoonyoung SungAbstract:Reliability as well as efficiency of transmissions is of a paramount issue for the safety critical services of VANET due to the urgency and/or significance of the Messages. To this end,various retransmission mechanisms have been studied for reliable broadcast Message Delivery in VANETs. Most of the existing approaches, though, rely on periodic beacons for retransmission decisions and intrinsically require high control overheads. Especially, in urban environments where the traffic density tends to be high, minimizing control overheads is important not only for the efficiency but also for the reliability of user Message Delivery. In this paper, we propose an efficient broadcast Message Delivery mechanism, which does not rely on the periodic beacon exchanges. Based on the observation that the broadcast Message Delivery could be particularly difficult at the intersections due to the signal diffraction and attenuation caused by the obstacles such as buildings around the corners of the intersection, a novel mechanism to make efficient and effective retransmissions across an intersection is proposed. Simulation results show that the proposed mechanism can provide similar or better reliability while incurring prominently less overheads than the existing approaches.
Guann-long Chiou - One of the best experts on this subject based on the ideXlab platform.
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An adaptive trajectory-based group Message Delivery protocol with detour support for vehicular networks
International Journal of Ad Hoc and Ubiquitous Computing, 2020Co-Authors: Guann-long Chiou, Shun-ren YangAbstract:To realise I2V group Message Delivery, some previously proposed protocols utilise the future trajectories of vehicles to deploy Message Delivery routes. However, we have noticed that none of these protocols consider that the destination vehicles may take unexpected detours, resulting in these vehicles no longer passing the rendezvous points. Thus, the detoured vehicles miss the Messages stored on the rendezvous points. To address this issue, this paper designs tc-eTGMD, which aims to redeploy only the routes for the detour vehicles when the detour events happen. Moreover, this scheme can guarantee the reaction time and can offload the traffic while handling the detour events. The specific contributions of this paper are as follows: (1) we formally formulate the trajectory-based I2V group Message Delivery with the detour events problem; (2) we give a detailed design of tc-eTGMD protocol and (3) we conduct extensive simulation experiments to evaluate tc-eTGMD's Message Delivery performance.
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On Trajectory-Based I2V Group Message Delivery Over Vehicular Ad-Hoc Networks
IEEE Transactions on Vehicular Technology, 2016Co-Authors: Guann-long Chiou, Shun-ren YangAbstract:In the literature, future vehicle trajectories have been exploited to improve the performance of challenging infrastructure-to-vehicle (I2V) group Message Delivery over vehicular ad-hoc networks (VANETs). The existing trajectory-based I2V group Message Delivery protocols typically consist of two phases. Based on the reported vehicle trajectories, phase one identifies an appropriate rendezvous point of the group Message and each of the member vehicles. Then, phase two composes a multicast tree to deliver the Message to these selected rendezvous points. The Message is kept at the rendezvous points for later last-hop Delivery when the member vehicles pass through. However, separately handling the rendezvous point selection and the multicast tree construction may significantly restrict the overall Message Delivery performance. This paper designs a novel trajectory-based I2V group Message Delivery protocol, i.e., eTGMD, for delay-tolerant vehicular applications. eTGMD iteratively selects a promising rendezvous point and extends the current multicast tree to cover the selected rendezvous point. Our specific contributions include the following: 1) We prove the trajectory-based I2V group Message Delivery problem's NP-hardness, 2) we theoretically analyze the worst-case performance bound and time complexity of eTGMD, and 3) we conduct extensive simulation experiments to evaluate eTGMD's Message Delivery performance.
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TGMD: A trajectory-based group Message Delivery protocol for Vehicular Ad Hoc Networks
2012 IEEE International Conference on Communications (ICC), 2012Co-Authors: Wan-han Hsieh, Shun-ren Yang, Guann-long ChiouAbstract:Infrastructure-to-vehicle (I2V) group Message Delivery is a common operation required by a wide variety of vehicular ad hoc network (VANET) applications. However, due to the highly dynamic mobility in VANETs, it remains a difficult problem to deliver Messages to a group of moving vehicles scattering over the whole network. The contribution of this paper is to propose the first trajectory-based I2V group Message Delivery protocol, TGMD, that exploits vehicle trajectories to improve the group-Message Delivery performance. TGMD contains two phases. The first phase determines a few rendezvous points from which the member vehicles can receive the Message. Then the second phase transmits the group Message over multiple hops to these selected rendezvous points using a multicast-like forwarding scheme to avoid redundant packet transmissions over the overlapped road segments. TGMD aims to minimize the required number of network-layer packet transmissions under a relatively loose delay constraint. Our extensive simulation results indicate that in comparison with the trajectory-based single-destination I2V Message Delivery scheme (through N-unicasting), TGMD significantly reduces the required number of packet transmissions (and thus bandwidth consumption) while achieving a high Delivery ratio around 90%.
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ICC - TGMD: A trajectory-based group Message Delivery protocol for Vehicular Ad Hoc Networks
2012 IEEE International Conference on Communications (ICC), 2012Co-Authors: Wan-han Hsieh, Shun-ren Yang, Guann-long ChiouAbstract:Infrastructure-to-vehicle (I2V) group Message Delivery is a common operation required by a wide variety of vehicular ad hoc network (VANET) applications. However, due to the highly dynamic mobility in VANETs, it remains a difficult problem to deliver Messages to a group of moving vehicles scattering over the whole network. The contribution of this paper is to propose the first trajectory-based I2V group Message Delivery protocol, TGMD, that exploits vehicle trajectories to improve the group-Message Delivery performance. TGMD contains two phases. The first phase determines a few rendezvous points from which the member vehicles can receive the Message. Then the second phase transmits the group Message over multiple hops to these selected rendezvous points using a multicast-like forwarding scheme to avoid redundant packet transmissions over the overlapped road segments. TGMD aims to minimize the required number of network-layer packet transmissions under a relatively loose delay constraint. Our extensive simulation results indicate that in comparison with the trajectory-based single-destination I2V Message Delivery scheme (through N-unicasting), TGMD significantly reduces the required number of packet transmissions (and thus bandwidth consumption) while achieving a high Delivery ratio around 90%.
Qian Zhang - One of the best experts on this subject based on the ideXlab platform.
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Message Delivery Capacity in Delay-Constrained Mobile Sensor Networks: Bounds and Realization
IEEE Transactions on Wireless Communications, 2011Co-Authors: Gabriel Y. Keung, Bo Li, Qian ZhangAbstract:In this paper, we study the Message Delivery capacity problem in delay-constrained mobile sensor networks. The Message Delivery capacity specifies the maximum percentage of sensing Messages that can be successfully delivered to sink nodes within a given time constraint. This captures the overall system capacity in terms of successful sensing Message Delivery. By taking full advantage of sensor mobility and rendezvous during senor node encounters, Messages can be delivered to a sink node either directly or through relays by other sensor nodes. In this paper, for the first time, we present the delay-constrained Message Delivery capacity formulation in mobile sensor networks. The objective is to maximize the Message Delivery capacity subject to the delay and buffering constraints. We first identify a number of unique challenges involved in such systems including Message relay and buffer replacement mechanisms, and we derive the capacity bound under perfect Message relay and buffer replacement mechanisms. Due to an unrealistic assumption about the foreknowledge of sensor moving trajectories, we next proceed to propose a practical algorithm to approximate the maximal Message Delivery capacity based on current global network knowledge. Furthermore, a distributed algorithm is proposed to reduce the control overhead for information exchange. Finally, we evaluate the algorithms and examine their sensitivity with respect to delay constraints, buffer size and Message relay, and replacement schemes.
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Message Delivery Capacity in Delay-Constrained Mobile Wireless Networks: Bounds and Realization
2010 IEEE International Conference on Communications, 2010Co-Authors: Gabriel Y. Keung, Bo Li, Qian ZhangAbstract:In this paper, we study the delay-constrained Message Delivery capacity formulation in mobile wireless networks. The Message Delivery capacity specifies the maximum percentage of Messages that can be successfully delivered to base stations within a given time constraint. By taking full advantage of node mobility and rendezvous during mobile node encounter, Messages can be delivered to a base station either directly or through relays by other nodes. We first identify a number of unique challenges involved in such systems including Message relay and buffer replacement mechanisms and then derive the capacity bound under perfect Message relay and buffer replacement mechanisms. We next prove that this problem is NP-hard. We proceed to propose a practical algorithm to approximate the maximal Message Delivery capacity. Finally, we evaluate the algorithm and examine the sensitivity with delay constraint, buffer size and Message relay and replacement schemes.
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ICC - Message Delivery Capacity in Delay-Constrained Mobile Wireless Networks: Bounds and Realization
2010 IEEE International Conference on Communications, 2010Co-Authors: Gabriel Y. Keung, Bo Li, Qian ZhangAbstract:In this paper, we study the delay-constrained Message Delivery capacity formulation in mobile wireless networks. The Message Delivery capacity specifies the maximum percentage of Messages that can be successfully delivered to base stations within a given time constraint. By taking full advantage of node mobility and rendezvous during mobile node encounter, Messages can be delivered to a base station either directly or through relays by other nodes. We first identify a number of unique challenges involved in such systems including Message relay and buffer replacement mechanisms and then derive the capacity bound under perfect Message relay and buffer replacement mechanisms. We next prove that this problem is NP-hard. We proceed to propose a practical algorithm to approximate the maximal Message Delivery capacity. Finally, we evaluate the algorithm and examine the sensitivity with delay constraint, buffer size and Message relay and replacement schemes.
Weihua Zhuang - One of the best experts on this subject based on the ideXlab platform.
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GLOBECOM - Delay Analysis for a Reliable Message Delivery in Sparse Vehicular Ad Hoc Networks
2010 IEEE Global Telecommunications Conference GLOBECOM 2010, 2010Co-Authors: Atef Abdrabou, Ben Liang, Weihua ZhuangAbstract:In this paper, we address the relation between Message Delivery delay and reliability for the communication between a vehicle and a road side unit (RSU). We focus on sparse or low density vehicular ad hoc networks (VANETs), where timely Message Delivery and reliable transmission are of significant importance. We present an exact Message Delivery delay distribution for a two-lane road, where vehicles in one direction act as Message carriers for the ones in the other direction and have the freedom to leave the road from randomly distributed exits with a certain probability. Our analysis offers a tool for an intelligent transportation system (ITS) service provider to determine the minimal separation between two consecutive RSUs for meeting a probabilistic requirement of the Message delay. Simulation results show the accuracy of our analysis.
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Delay Analysis for a Reliable Message Delivery in Sparse Vehicular Ad Hoc Networks
2010 IEEE Global Telecommunications Conference GLOBECOM 2010, 2010Co-Authors: Atef Abdrabou, Ben Liang, Weihua ZhuangAbstract:In this paper, we address the relation between Message Delivery delay and reliability for the communication between a vehicle and a road side unit (RSU). We focus on sparse or low density vehicular ad hoc networks (VANETs), where timely Message Delivery and reliable transmission are of significant importance. We present an exact Message Delivery delay distribution for a two-lane road, where vehicles in one direction act as Message carriers for the ones in the other direction and have the freedom to leave the road from randomly distributed exits with a certain probability. Our analysis offers a tool for an intelligent transportation system (ITS) service provider to determine the minimal separation between two consecutive RSUs for meeting a probabilistic requirement of the Message delay. Simulation results show the accuracy of our analysis.
