Shin Yongje, Choi Hyunseok, Nam Youngju, Lee Euisin
School of Information and Communication Engineering, Chungbuk National University, Cheongju 28644, Korea.
Sensors (Basel). 2021 Nov 5;21(21):7368. doi: 10.3390/s21217368.
By leveraging the development of mobile communication technologies and due to the increased capabilities of mobile devices, mobile multimedia services have gained prominence for supporting high-quality video streaming services. In vehicular ad-hoc networks (VANETs), high-quality video streaming services are focused on providing safety and infotainment applications to vehicles on the roads. Video streaming data require elastic and continuous video packet distributions to vehicles to present interactive real-time views of meaningful scenarios on the road. However, the high mobility of vehicles is one of the fundamental and important challenging issues for video streaming services in VANETs. Nevertheless, previous studies neither dealt with suitable data caching for supporting the mobility of vehicles nor provided appropriate seamless packet forwarding for ensuring the quality of service (QoS) and quality of experience (QoE) of real-time video streaming services. To address this problem, this paper proposes a video packet distribution scheme named Clone, which integrates vehicle-to-vehicle and vehicle-to-infrastructure communications to disseminate video packets for video streaming services in VANETs. First, an indicator called current network quality information (CNQI) is defined to measure the feature of data forwarding of each node to its neighbor nodes in terms of data delivery ratio and delay. Based on the CNQI value of each node and the trajectory of the destination vehicle, access points called clones are selected to cache video data packets from data sources. Subsequently, packet distribution optimization is conducted to determine the number of video packets to cache in each clone. Finally, data delivery synchronization is established to support seamless streaming data delivery from a clone to the destination vehicle. The experimental results show that the proposed scheme achieves high-quality video streaming services in terms of QoS and QoE compared with existing schemes.
随着移动通信技术的发展以及移动设备功能的增强，移动多媒体服务在支持高质量视频流服务方面变得日益突出。在车载自组织网络（VANET）中，高质量视频流服务专注于为道路上的车辆提供安全和信息娱乐应用。视频流数据需要向车辆弹性且持续地分发视频数据包，以呈现道路上有意义场景的交互式实时视图。然而，车辆的高移动性是VANET中视频流服务面临的一个基本且重要的挑战性问题。尽管如此，先前的研究既未处理支持车辆移动性的合适数据缓存问题，也未提供适当的无缝数据包转发以确保实时视频流服务的服务质量（QoS）和体验质量（QoE）。为了解决这个问题，本文提出了一种名为Clone的视频数据包分发方案，该方案整合了车对车和车对基础设施通信，以在VANET中传播用于视频流服务的视频数据包。首先，定义了一个名为当前网络质量信息（CNQI）的指标，用于从数据传输率和延迟方面衡量每个节点向其邻居节点进行数据转发的特性。基于每个节点的CNQI值和目标车辆的轨迹，选择称为克隆点的接入点来缓存来自数据源的视频数据包。随后，进行数据包分发优化以确定每个克隆点要缓存的视频数据包数量。最后，建立数据传输同步以支持从克隆点到目标车辆的无缝流数据传输。实验结果表明，与现有方案相比，所提出的方案在QoS和QoE方面实现了高质量的视频流服务。
