In the light of Industry 4.0 revolution, the Industrial Internet of Things (IIoT) allows digitalizing manufacturing processes and increasing the digital connectivity and automation in the smart factories and industrial systems. The reliability of a system is considered as a key performance indicator that defines how accurately and perfectly the system works. Ensuring reliability in the IIoT systems presents several challenges due to the presence of uncertain and dynamics in the industry environment as well as the complex nature of industrial systems. While there are no standard frameworks proposed and applied for the IIoT systems with multiple reliability levels, the challenges reveal many promising opportunities for the research and practical implementation including advancing technologies and systematic designs such as algorithms, architectures, and devices. However, there are a few works studying the reliability-related aspects of the industrial systems in the existing literature, they lack a framework to conduct the study and examination of reliability of IIoT systems in a holistic manner. In this regard, this article will elucidate and survey several performance-improvement methods and techniques for better reliability and further challenges to be overcome for highly reliable IIoT systems. Finally, by defining several open research issues, we expect to draw more attention for both the academic researchers and practitioners toward designing and developing reliable solutions and frameworks.

鉴于工业 4.0 革命，工业物联网 (IIoT) 允许数字化制造过程并增加智能工厂和工业系统中的数字连接和自动化。系统的可靠性被视为关键性能指标，它定义了系统工作的准确性和完美程度。由于工业环境中存在不确定性和动态性以及工业系统的复杂性，确保 IIoT 系统的可靠性面临多项挑战。虽然没有针对具有多个可靠性级别的工业物联网系统提出和应用的标准框架，但这些挑战揭示了研究和实际实施的许多有希望的机会，包括先进的技术和系统设计，如算法、架构、和设备。然而，现有文献中很少有研究工业系统可靠性相关方面的工作，它们缺乏一个框架来以整体方式对 IIoT 系统的可靠性进行研究和检查。在这方面，本文将阐明和调查几种性能改进方法和技术，以提高可靠性并克服高度可靠的 IIoT 系统面临的进一步挑战。最后，通过定义几个开放的研究问题，我们希望吸引学术研究人员和从业人员更多地关注设计和开发可靠的解决方案和框架。他们缺乏以整体方式对 IIoT 系统的可靠性进行研究和检查的框架。在这方面，本文将阐明和调查几种性能改进方法和技术，以提高可靠性并克服高度可靠的 IIoT 系统面临的进一步挑战。最后，通过定义几个开放的研究问题，我们希望吸引学术研究人员和从业人员更多地关注设计和开发可靠的解决方案和框架。他们缺乏以整体方式对 IIoT 系统的可靠性进行研究和检查的框架。在这方面，本文将阐明和调查几种性能改进方法和技术，以提高可靠性并克服高度可靠的 IIoT 系统面临的进一步挑战。最后，通过定义几个开放的研究问题，我们希望吸引学术研究人员和从业人员更多地关注设计和开发可靠的解决方案和框架。