OPC-UA protocol S/W and microservices

Description

In these days, various data transmission protocols are used in the factory system according to the vendors and machines. To make efficient communication scheme from the data srouce to the data service for smart factory solution, data protocol shoud be integrated one way. OPC-UA( Open Platform Communication United Architecture ) is one of the well-known data tranmission protocol for industrial technology. It can be the most desirable way with very high possibility, we expect. The OPC-UA protocol could be used entire smart factory data pipeline ( industrial things - edge device - cloud service ), so the microservices that used OPC-UA protocol could be located in the device service layer and the export service layer either. Therefore, the code repositories are separated into protocol S/W part and microservice part. The protocol S/W is provided with Java and C ( based on open62541, until Feb. 2018) version. For the Java version protocol S/W, it is based on the OPC-UA milo open source. The external open sources are not included in the repository, when you try to build protocol S/W, the milo open source will be downloaded in your build environment. And the microservices are provided as Device Service ( based on Device Service SDK of EdgeX ) and Export Service ( planned ). Also when you try to build the OPC-UA device service, the OPC-UA protocol S/W is automatically downloaded. 

Requirements

for OPC-UA protocol S/W

• OPC-UA client could establish connection with the OPC-UA server. ( connect procedure from OPC-UA specification )
• OPC-UA client could browse data node on the OPC-UA server. ( browse procedure from OPC-UA Service specification )
• OPC-UA client could access data node on the OPC-UA server. ( attribute service procedure from OPC-UA Service specification )
• OPC-UA client could monitor data node on the OPC-UA server. ( pub/sub procedure from OPC-UA Service specification )

for OPC-UA device service

• System( OPC-UA device service ) could process command requests from/to the OPC-UA protocol devices.
• System could publish data stream to the other microservices.
• System could update metadata with the OPC-UA protocol device attributes.

Design

The attached documents describe the high level design consideration.

• OPC-UA protocol S/W & device service

Code repository

https://github.com/mgjeong/protocol-opcua-java

https://github.com/mgjeong/device-opcua-java

Current status

• Verifiy the CTT compliance using  OPC-UA protocol S/W written in Java.
• Verify the interoperability with PROSYS OPC-UA S/W.
• Verify the interoperability with EdgeX core components ( Metadata , Command, Coredata, Registry&Config )
  • One proposal related Command microservice is going to be raised.
• CTT test is on going for OPC-UA protocol S/W written in C. ( is going to be finished Feb. 2018 )