In the future 5G paradigm, billions of machinetype devices will be deployed to enable wide-area and ubiquitous data sensing, collection, and transmission. Considering the traffic characteristics of machine-to-machine (M2M) communications and the spectrum shortage dilemma, a cost-efficient solution is to share the underutilized spectrum allocated to human-to-human (H2H) users with M2M devices in an opportunistic manner. However, the implementation of large-scale spectrum sharing in 5G heterogeneous networks confronts many challenges, including lack of incentive mechanism, privacy leakage, security threats, and so on. This motivates us to develop a privacy-preserved, incentive-compatible, and spectrum-efficient framework based on blockchain, which is implemented in two stages. First, H2H users sign a contract with the base station for spectrum sharing, and receive dedicated payments based on their contributions. Next, the shared spectrum is allocated to M2M devices to maximize the total throughput. We elaborate the operation details of secure spectrum sharing, incentive mechanism design, and efficient spectrum allocation. A case study is presented to demonstrate the security and efficiency of the proposed framework. Finally, we outline several open issues and conclude this article.

中文翻译：

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适用于5G异构网络的基于区块链的安全频谱共享

在未来的5G范式中，将部署数十亿台机器类型的设备，以实现广域和无处不在的数据感测，收集和传输。考虑到机器对机器（M2M）通信的流量特性和频谱短缺的困境，一种经济高效的解决方案是以机会主义方式与M2M设备共享分配给人对人（H2H）用户的未充分利用的频谱。但是，在5G异构网络中实现大规模频谱共享面临许多挑战，包括缺乏激励机制，隐私泄漏，安全威胁等。这激励我们开发基于区块链的隐私保护，激励兼容且频谱有效的框架，该框架分两个阶段实施。第一，H2H用户与基站签订了频谱共享合同，并根据他们的贡献获得专用付款。接下来，将共享频谱分配给M2M设备以最大化总吞吐量。我们详细阐述了安全频谱共享，激励机制设计和有效频谱分配的操作细节。案例研究表明了所提出框架的安全性和有效性。最后，我们概述了几个未解决的问题并总结了本文。案例研究表明了所提出框架的安全性和有效性。最后，我们概述了几个未解决的问题并总结了本文。案例研究表明了所提出框架的安全性和有效性。最后，我们概述了几个未解决的问题，并总结了本文。