Experiences Modeling a OPC UA / DDS Gateway in AADL in the Context of Fog Computing

摘要

The legacy protocols still used in industrial automation are an obstacle to interoperability. In the meantime, while newer protocols are slowly replacing gateways, they can provide a bridge between new and legacy protocols. The Architecture Analysis & Design Language (AADL) was used in the Fog Computing for Robotics and Industrial Automation (FORA) project to model a Fog Computing Platform (FCP). Part of the FCP is an OPC Unified Architecture (OPC UA) / Data Distribution Service (DDS) gateway. The main goal was to develop an AADL model that allows the creation of platform-specific instances of such a gateway and the creation of other gateways. While the gateway model is incomplete, it formed the basis for several gateway prototypes. Challenges included complex data structures and tooling issues related to code generation. Nevertheless, the experiences with the AADL modeling of the gateway and the FCP were positive overall.