I welcome you to the fourth issue of the IEEE Communications Surveys and Tutorials in 2021. This issue includes 23 papers covering different aspects of communication networks. In particular, these articles survey and tutor various issues in “Internet Technologies,” “Network Security,” “Network Virtualization,” “Optical Communications,” “Vehicular and Sensor Communications,” and “Wireless Communications.” A brief account for each of these papers is given below.

中文翻译：

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IEEE 通信调查和教程


欢迎您阅读 2021 年第四期 IEEE 通信调查和教程。本期包括 23 篇论文，涵盖通信网络的不同方面。特别是，这些文章调查并指导了“互联网技术”、“网络安全”、“网络虚拟化”、“光通信”、“车辆和传感器通信”和“无线通信”中的各种问题。下面对每篇论文进行简要说明。