Industrial Internet of Things (IIoT) technologies have revolutionized industrial processes, enabling smart automation, real-time data analytics, and improved operational efficiency across diverse industry sectors. IIoT testbeds play a critical role in advancing IIoT research and development (R&D) to provide controlled environments for technology evaluation before their real-world deployment. In this article, we conduct a comprehensive literature review on existing IIoT testbeds, aiming to identify benchmark performance, research gaps and explore emerging trends in IIoT systems. We first review the state-of-the-art resource management solutions proposed for IIoT applications. We then categorize the reviewed testbeds according to their deployed communication protocols (including TSN, IEEE 802.15.4, IEEE 802.11 and 5G) and discuss the design and usage of each testbed. Driven by the knowledge gained during this study, we present suggestions and good practices for researchers and practitioners who are planning to design and develop IIoT testbeds for connectivity research.

翻译：工业物联网技术已彻底变革了工业流程，实现了智能自动化、实时数据分析，并提升了各行业部门的运营效率。工业物联网测试平台在推动工业物联网研发（R&D）中发挥着关键作用，为技术在现实部署前提供受控评估环境。本文对现有工业物联网测试平台开展系统性文献综述，旨在识别基准性能、研究空白，并探索工业物联网系统中的新兴趋势。我们首先梳理了面向工业物联网应用的最新资源管理方案。随后，根据已部署的通信协议（包括TSN、IEEE 802.15.4、IEEE 802.11及5G）对综述的测试平台进行分类，并讨论各测试平台的设计与用途。基于本研究获得的知识，我们为计划设计和开发面向连接性研究的工业物联网测试平台的研究人员及实践者提出了建议与最佳实践。