Vehicular ad hoc networks ( VANETs ) and the services they support are an essential part of intelligent transportation. Through physical technologies, applications, protocols, and standards, they help to ensure traffic moves efficiently and vehicles operate safely. This article surveys the current state of play in VANETs development. The summarized and classified include the key technologies critical to the field, the resource-management and safety applications needed for smooth operations, the communications and data transmission protocols that support networking, and the theoretical and environmental constructs underpinning research and development, such as graph neural networks and the Internet of Things. Additionally, we identify and discuss several challenges facing VANETs, including poor safety, poor reliability, non-uniform standards, and low intelligence levels. Finally, we touch on hot technologies and techniques, such as reinforcement learning and 5G communications, to provide an outlook for the future of intelligent transportation systems.

中文翻译：

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车载自组织网络关键技术和挑战的综合调查

车载自组织网络(VANET) 及其支持的服务是智能交通的重要组成部分。通过物理技术、应用程序、协议和标准，它们有助于确保交通高效移动和车辆安全运行。本文调查了 VANETs 开发的当前状态。总结和分类的内容包括对该领域至关重要的关键技术、平稳运行所需的资源管理和安全应用、支持网络的通信和数据传输协议，以及支撑研究和开发的理论和环境结构，例如图神经网络和物联网。此外，我们确定并讨论了 VANET 面临的几个挑战，包括安全性差、可靠性差、标准不统一和智能水平低。最后，