Julius and Team
New open62541 Website – Interview with Götz Görisch
A new look-and-feel for http://www.open62541.org.
A few days ago the new website of open62541 was put online. Thanks Andreas Ebner for this!
With the new website we also started a series of technical articles on
open62541 and interviews with community members.
First up is
an interview with Götz Görisch of the German Machine Tool Builders` Association
We also include his interview in this community newsletter.
1. Who are you and what is your role at VDW?
Hi, my name is Götz Görisch. I work at the German Machine Tool Builders` Association (VDW – Verein Deutscher Werkzeugmaschinenfabriken e.V.) as the expert for digitization and open interfaces. I am the elected chairperson for the “OPC UA for Machine Tools joint working group” with the OPC Foundation. In this position I’m leading the companion spec work for OPC 40501 (UA4MT) and 40502 (UA4CNC). Additional I’m an “umati evangelist” for the umati community to drive the adoption of OPC UA in the machine building industries. Eight of the VDW’s members constitute the “core group” which leads the way to develop the OPC UA standards. I coordinate these activities. We are supported by the Institute for Control Engineering of Machine Tools and Manufacturing Units (ISW) from the University of Stuttgart; therefore, it is my pleasure to also introduce Christian von Arnim. He is Research Assistant and is doing most of the work concerning open62541 on our behalf. The browser-based dashboard application at the EMO 2019 was mostly developed by him. Apart from OPC UA, his research area is “reconfigured real-time production networks”.2. Since when do you know and use OPC UA and the open62541 SDK?
I’m deeply involved in the OPC community since 2018 and already back then I got the attention for open62541. Originally, we started this companion specification work in 2017 with a commercial C++ SDK, which supported us until 2019. Christian von Arnim started working with OPC UA in 2014. After open62541 was chosen as the most promising Open Source OPC UA SDK in his research project back in 2017, he realized several projects using this SDK.3. Within the universal machine technology interface (umati), the OPC UA standard is an important part of the solution. What advantages and added value do you see in the use of OPC UA?
Although we have “interface” in the name, I would like to resolve the misunderstanding that this is an interface standard. Behind umati is a community of more than 200 partners who share the vision to enable “Plug and Play” for the machine building industry users. Therefore, on the one hand we are developing together with the VDMA and the OPC-Foundation companion specifications to create the Global Production Language based on OPC UA with machine information interoperability. On the other hand, the partners join forces to solve the technical challenges and develop solutions together for the sake of their customers. The Open-Source OPC UA community and open62541 play a crucial role to achieve this goal together. A success story in this regard for the machine tool and woodworking groups to extend open62541 and to upstream feature development can be found at https://umati.org/weinig-group-introduces-woodworking-companion-spec-into-umati-sample-server/ and the https://umati.org/dashboard-opc-ua-client/.4. Why did you or the VDW choose the open62541 library for the implementation of the umati standard?
As said above, umati is not a standard. It is a community to drive adoption of OPC UA and Open Source in the machinery industry. Specifically, the development of the OPC 40501-1 “UA for Machine Tools” specification led to amendments of the UA base specification. Suddenly, our CS was in the front line of OPC UA development. We noticed that commercial SDKs could not keep up with this rapid development as their development cycles are slower. Hence, this delayed the implementation of our specification in the products of our partners. Therefore, in the end of 2019, we started to develop a Sample Server for UA4MT to use throughout the remaining work ahead and to open source this implementation as a base for the community, other groups and interested parties in the companion specifications.5. What added value do you see in using the open6254- OPC UA SDK’s?
open62541 gave us the flexibility to implement the new features of the base UA specification during the development phase of the specification amendment. Therefore, we were able to have a running server according to spec the day after the release of the new UA version. Our members who were relying on commercial products and SDK had to wait 3-9 month before the new base specification was available to them. This was for my personal the pivot point to fully endorse the development work with Open-Source SDKs like open62541. Furthermore, the ability to fix bugs in the OPC UA SDK by us or partners like Weinig or basysKom, without the need to wait for a next release, greatly improved the development speed. Additionally, the are no runtime license costs and they can be directly reinvested in features and bug fixes. Lastly, an Open-Source SDK like open62541 typically give the users the ability to run on different platforms, Win, Linux, x86, arm64 or in container images without porting costs.6. What role do open source libraries play for you in the implementation of umati?
For UA4MT we are also looking to provide sample implementations of servers and clients, we are doing this based on open62541, node-opcua and opcua-asyncio. Additionally with the machine tools group we started a project to further standardize towards underlying systems, which led to the first publication of a TransformationEngineAPI and will continue to get an Open Source reference implementation in 2022, where we for sure will make use of other related libraries. For demonstration purpose we also build and continue to develop a dashboard application running at https://umati.app. This is also relying on more than 1000 Open-Source Projects from npm community to make this a reality. Also, there we are trying to provide bug fixes to the upstream projects.
Thank you to the open62541 for this great project to make OPC UA in the industry based on Open Source a reality.
open6241 @ Hannover Fair
This year did
we again present open62541 at the Hannover Fair. See below the “partner pod” at
the booth of the OPC Foundation. It was great connecting with the community directly
after two years of remote work.
Thanks also to OSADL and Kalycito for co-organizing the booth
(Andreas Ebner and Julius Pfrommer at Hannover Fair 2022)
1. Patch Release v1.2.5 and v1.3.1
We received a responsible disclosure of a security issue from Team 82 / Claroty.
The default configuration of open62541 allowed for messages of unlimited size / unlimited number of chunks.
This can obviously be used for a denial-of-service attack for OPC UA applications on constrained devices.
The v1.2.5 and v1.3.1 patch releases rectify the issue (on master as well).
The new default are messages up to 512 MB comprised of up to 16k chunks.
Users of older versions are advised to adjust the settings in the client/server configuration.
2. JSON5 Parsing Backend
JSON5 is a superset of the JSON standard with many usability improvements (https://json5.org/).
open62541 now includes the possibility to parse JSON5. This will be used in the future for textfile-based configuration.
Going forward, the parsing of the OPC UA data types will be switched over to the new JSON5 backend as well.
That way, configuration textfiles can include OPC UA data types in the JSON encoding that are automatically decoded.
3. Server switched to the EventLoop model
A lot of work went into the EventLoop model of the core control flow in open62541.
The server is now switched over to the EventLoop. The Client, PubSub and Discovery subsystems are now being switched over as well.
The EventLoop aggregates all network interactions into a single "select" syscall.
This will enable performant networking with many protocols (OPC UA Binary, PubSub UADP, PubSub MQTT, IP Multicast Discovery and in the future also HTTP, AMQP, etc.) and allows the concurrent operation of multiple servers and clients in a single thread.
Eventually the EventLoop will act as the uniform hardware-abstraction-layer interface so that the core open62541 library is maximally portable and can "converge" to a stable state.
Community Call on June 15
The next community call (via MS Teams) will take
place on June 15 at 17:00 (CET).
Attached also as an Outlook-Calendar event in the .ics format.
Phone-In: +49 69 365057687,,979095389#
Do you want to receive these mailings?
this email because your are either registered to the open62541 Google Group
(mailing list) or are listed as a “power user” to get notifications (also
security-related advance notice).
If you do not want to receive these mails, shoot us a quick message and we take you off the list.