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(IIoT)技术已彻底变革工业流程，在多个行业领域实现了智能自动化、实时数据分析及运营效率提升。IIoT测试平台通过提供技术实际部署前的受控评估环境，对推动IIoT研发具有关键作用。本文对现有IIoT测试平台进行全面文献综述，旨在确立性能基准、识别研究空白并探索IIoT系统新兴趋势。首先回顾了为IIoT应用提出的前沿资源管理方案，继而依据测试平台采用的通信协议（包括TSN、IEEE 802.15.4、IEEE 802.11及5G）进行分类，并逐一探讨各测试平台的设计与应用。基于本研究获得的认识，我们为计划设计和开发IIoT连接性研究测试平台的研究者与实践者提供了建议与最佳实践方案。