In case you haven’t seen this news yet, the OPC Foundation has renamed OPC Xi to OPC .NET 3.0 (WCF). Let’s call it OPC .NET 3.0 for short. It’s the same client/server connectivity standard and functionality for the process industries that I’ve been describing as OPC Xi in earlier posts.
I turned to Emerson’s Chris Felts and Lee Neitzel, whom you may recall from earlier OPC-related posts and asked what this change means. Lee shared the following key points with me that your IT staff members may find of interest:
- Xi has been renamed to OPC .NET 3.0 (WCF) to make its intention and use more apparent.
- With OPC .NET 3.0:
- OPC standardizes a Windows Communication Foundation (WCF) interface for OPC Classic servers.
- OPC standardizes a standard OPC Client application programming interface (API) for accessing both OPC Classic servers via WCF and for accessing OPC UA servers via the UA protocol.
- OPC provides a standard OPC .NET wrapper for OPC Classic servers in the form of source code to allow it to be adapted to any .NET platform.
- OPC provides a standard OPC .NET Client Proxy for WCF that supports the standard OPC Client API for access.
- OPC will begin development of a standard UA Client Proxy that supports the standard OPC Client API for access and that can coexist with the OPC .NET Client Proxy.
With Windows-based client developments moving to Microsoft’s .NET framework, these applications needed a native .NET interface to talk to existing OPC Classic (COM-based) servers. The alternative was that each application needed to have its own interface developed separately.
At the Emerson Exchange, Lee and Chris gave a presentation on this topic with respect to the DeltaV system. With the OPC name change, their presentation has been updated and renamed, OPC .Net 3.0 Simplifies Client Access to DeltaV. Instead of the application developer designing security into the application, this OPC .NET standard has this security built in at the .NET level. Some of these functions include the assignment of firewall ports through which to communicate, disablement of the standard web browser port 80, unused port lockdown, specifically configured individual client connections, and encrypted communications.
Lee and Chris shared some of the robustness capabilities in the .NET framework such as automatic recovery from a connection failure without losing configuration between the server and client. There are plenty of architectural drawings and block diagrams to highlight performance, communications paths, interfaces and more. The first 16 slides give a great overview for automation professionals and the balance of the presentation provides a deeper level for IT developers with existing or planned OPC implementations.
