I4.0-Device Integration: A Qualitative Analysis of Methods and Technologies Utilized by System Integrators: Implications for Enginering Future Industrial Internet of Things System

Describing software component interfaces with a machine-readable language is not new in software architecture research. Although there has been significant research effort and success stories, formal languages have not yet been applied widely in industrial settings. Besides reasons such as low usability or a bad effort to benefit ratio, almost all available interface description languages rely on the assumption that every use case has to be defined during design time. This may be possible for a small number of IoT-device interfaces in a topdown defined use-case scenario but is hard to achieve for the distributed emergence of such devices. Current device integration approaches fall short for desired future IoT characteristics such as self-adaptive or semantic interoperability. For "smarter" integration methods that scale with the increasing number of IoT devices, the reason of such shortcomings must be clearly understood from both, a practical and scientific viewpoint. This paper presents practical experiences when connecting IoT-Systems at different levels of abstractions.