Industrial Internet of Things covers all aspects of networked intelligent manufacturing systems. This means covering a wide array of application domains and user requirements. In such scenarios it is not feasible to define a single protocol for all situations. Hence, a multi-protocol approach is required. OPC UA has strong backing from Industry 4.0 as the protocol for the Industrial Internet of Things. Interoperability of OPC UA has been investigated in the context of migration from legacy and with protocols such as DPWS. Additionally HTTP and CoAP have been investigated as possible transport mediums. However, OPC UA interoperability has not been investigated within a multi-protocol settings and no generic protocol translation exists. This paper proposes an OPC UA translator following the service translator model proposed in the Arrowhead project. Utilizing a mapping to intermediate format, it can be used along side CoAP, HTTP and MQTT protocols.

Protocol interoperability of OPC UA in service oriented architectures

Ope UA is one of the most important communication protocols for Industry 4.0 applications in the automation domain. However, to really reach the status of an Internet-of-Things protocol, OPC UA also has to give some answers to upcoming cross-domain questions. Only if OPC UA is able to bridge the gap between several different domains, it will be accepted as real Internet-of-Things protocol and therefore supported even better by the APIs of the big IT players. One technology which already interconnects nearly every domain is the REST architecture. A lot of research already focused on the combination of these two technologies. However, in this paper we will show the first approach which covers all OPC UA requirements and therefore enables also use cases like server reconfiguration. We will also give some insights into our concept, which was contributed to the OPC UA specification as part of the Vl.04 release.

REST based OPC UA for the IIoT

Over the past years, Internet of Things (IoT) has been emerging with connected and smart things that can communicate with each other and exchange information. Similarly, with the emergence of Industry 4.0, the industrial world is also undergoing a strong evolution by connecting devices, sensors and machines to the Internet. In this paper, we investigate the integration of these two domains and examine the interconnection of two of the promising interoperability standards in these domains, namely OPC Unified Architecture and Lightweight Machine-to-Machine (LwM2M) protocol. For this purpose, we introduce an efficient and scalable approach, based on Docker Containers, for the cross-domain integration and interoperation. Besides, we also demonstrate and validate our interoperability approach by means of real world implementations and also theoretical and practical analysis.

https://biblio.ugent.be/publication/8612866/file/8612868.pdf

The Integration of LwM2M and OPC UA: An Interoperability Approach for Industrial IoT

This thesis details the design of a protocol translator between the industrial-automation protocol OPC UA, and HTTP. The design is based on the architecture of the protocol translator of the Arrowh ...

Integration of OPC Unified Architecture with IIoT Communication Protocols in an Arrowhead Translator

Rapid advances in digitalization are leading the automation and manufacturing sector towards the fourth industrial revolution also known as Industry 40, whose main goal is to realize the changeable production processes, which is currently expensive and effort-intensive The Open Platform Communications Unified Architecture (OPC UA) is an established and well-known communication protocol in the industrial domain The Reference Architecture Model Industry40 (RAMI 40) proposes OPC UA as the core communication protocol among assets such as machines, robots, and appliances Despite the key role of OPC UA in Industry 40, there is still a lack of technical guidance on how to integrate OPC UA with other communication protocols, especially with legacy devices that communicate through proprietary protocols To address this challenge, we propose a solution that is characterized by a set of communication primitives, a platform-independent type system and an intermediate language We also evaluate the overhead created through integration in terms of the round-trip time and message size imposed by metadata for abstraction We have implemented the proposed approach in reference Industry 40 projects, and in this paper, we report our experiences in integrating OPC UA in a homogeneous communication system comprised of Create, Read, Update, Delete and Invoke primitives which improves the protocol interoperability and reduces integration effort

Enabling Industry 4.0 Communication Protocol Interoperability: An OPC UA Case Study

OPC Unified Architecture (OPC UA) is a data exchange specification
that provides interoperability in industrial automation. With the
arrival of Industry 4.0, it is of great importance to implement the
exchange of semantic information utilizing OPC UA Transmitting in
CoAP. This document provides some transmission methods for message of
OPC UA over CoAP.

Jianqiang Hou

Papers

OPC UA Message Transmission Method over CoAP