What is OPC Unified Architecture?
The OPC Unified Architecture, also known as OPC-UA, is the latest open-standard architecture developed by the OPC Foundation to improve and expand interoperability standards in the Industrial Automation Industry.
Why do we need OPC UA?
OPC-UA was the result of several advancements and changes in the way data was commonly being accessed and exchanged. Some changes that lead to the need for a new architecture include:
- Microsoft's COM and DCOM (the basis for previous standards) were deprecated and are now considered legacy technologies
- Web services gained importance in data exchange between machines and for communications to factory floor devices
- Earlier specifications were decoupled and did not integrate well, e.g. items in a Data Access server could not communicate directly with items in an Alarms and Events server.
OPC-UA is designed for exchanging information in an object-oriented manner, rather than as isolated data points. This increases the accessibility of your plant floor data by letting you re-use information stored in a common object. OPC-UA also incorporates a service-oriented model, which increases interoperability with other platforms and improves security.
OPC-UA is not a replacement for existing OPC-DA standards. Because of the layered design of this architecture it includes all the functionality of existing OPC-DA servers, but expands upon their functionality with a common interoperability layer. This interoperability layer unifies information exchange and provides a common interface for controlling processes.
How does OPC UA work in OmniServer?
Starting with OmniServer V2.7, OmniServer Server Edition and the OmniServer Professional Edition give you access to the new OPC UA Server interface, in addition to the existing client interfaces. See the link below for more detailed information:
OmniServer OPC UA Online Resources
What are the Benifits of OPC UA?
OPC-UA provides a way to connect clients and servers in a secure manner, without relying on Microsoft DCOM . This is a big advantage because it means that you are no longer saddled with the headaches associated with having to configure DCOM. This is because DCOM plays no role in data transport.
OPC-UA can also allow users to make secure connections through firewalls and over VPN connections . In addition, it expands the ability to provide factory floor information to other business systems, as a result of the object-oriented model described above.