In the modern world, the connectivity-as-we-go model is gaining popularity. Internet-of-Things (IoT) envisions a future in which human beings communicate with each other and with devices that have identities and virtual personalities, as well as sensing, processing, and networking capabilities, which will allow the developing of smart environments that operate with little or no human intervention. In such IoT environments, that will have battery-operated sensors and devices, energy efficiency becomes a fundamental concern. Thus, energy-efficient (EE) connectivity is gaining significant attention from the industrial and academic communities. This work aims to provide a comprehensive state-of-the-art survey on the energy efficiency of medium access control (MAC) protocols for cellular IoT. we provide a detailed discussion on the sources of energy dissipation at the MAC layer and then propose solutions. In addition to reviewing the proposed MAC designs, we also provide insights and suggestions that can guide practitioners and researchers in designing EE MAC protocols that extend the battery life of IoT devices. Finally, we identify a range of challenging open problems that should be solved for providing EE MAC services for IoT devices, along with corresponding opportunities and future research ideas to address these challenges.

翻译：在现代世界,互联互通模式越来越受欢迎; 互联网互连互通模式(Io-We-go)展望未来,人类彼此交流,并与具有身份和虚拟人格的装置以及遥感、处理和联网能力进行交流,从而能够发展智能环境,在人类很少或根本没有干预的情况下运作; 在互联网互连互通模式环境中,使用电池操作的传感器和装置,能源效率成为基本问题; 因此,工业和学术界对节能(EEE)互连互通正在给予极大关注; 这项工作旨在提供对手机互连互通协议的能源效率进行最新全面调查。 我们详细讨论了在计算机互连互通系统层的能源流失问题,然后提出了解决办法; 除了审查拟议的计算机互连互连互连互连互通模式的设计外,我们还提供各种见解和建议,指导从业人员和研究人员设计扩大信息互连通设备的电池寿命的电子电子互连通协议。 最后,我们查明了一系列挑战性的问题,这些问题应当解决,以便提供电子互连通控制(MAC)协议(MAC)对未来研究设备提供E MAC服务的挑战,同时解决这些机遇。