MStudio 8.1 & Deprecation of DataSocket

[ddunne]

Hello;

I've been evaluation Measurement Studio 8.0.1 for the last couple of weeks.  I have not only been impressed by the UI controls, but the ease of connecting to OPC servers through DataSocket, as well as publishing data to DataSocket (i.e., basically creating custom hardware drivers).

Now with the new release of 8.1, the DataSocket has been deprecated, seemingly in favor of "network variables".  Does this mean that moving forward, Measurement Studio will no longer be able to connect to OPC servers, or is this going to be possible with the Network Variables (after initial inspection, I don't see how to do it)?  I know the DataSocket is still available, but I am hesitant to create new software using deprecated tools.

This is a very important issue for me, as I was about to purchase Measurement Studio.  But without the connectivity to OPC Servers, I may be forced to look elsewhere.

Thanks,

Derrick Dunne

[JonathanN]

Hi Derrick,

The

[drohacek]

Derrick -

I'd like to add to Jonathan's response.

In general, the Network Variable library provides better performance than DataSocket and its performance scales better for large numbers of connections and large amounts of data. This is why we are deprecating DataSocket in favor of Network Variable. These performance differences are more of an issue with the native protocols (dstp: and psp:) than they are with OPC (opc:).

Despite this deprecation, we do not plan to remove the DataSocket library from the product, for compatibility reasons. However, there are no plans for new feature development of DataSocket. You can consider it to be in maintenance mode. We do plan on supporting it on Windows Vista. We do not plan to develop a 64-bit version of DataSocket (though the 32-bit version should run fine on a 64-bit OS). If a new version of the .NET CLR is released, it is unlikely that we will create a new version of the DataSocket library to support it (instead we would rely on the CLR's backward compatibility). Basically, if you create a system today that works with it and you won't need to evolve that system greatly over a long period of time, you can be comfortable in using it.

As Jonathan mentioned, you can use Network Variable to talk OPC as long as LabVIEW DSC is in the picture. One correction to Jonathan's statement is that you need only the DSC run time, not the LabVIEW DSC development module. Additionally, you need to install the DSC run time only on the machine that will host the Network Variable engine that you will use to host the OPC variables. This page (https://www.ni.com/en-us/shop/product/labview-datalogging-and-supervisory-control-module.html) shows the DSC product options.

Let us know if you have additional questions.

David Rohacek
National Instruments

[ddunne]

Thanks for the information!

Although NI plans on keeping DataSocket around, it is difficult for me at this point to estimate if our product will evolve beyond the current capabilities of DataSocket.  That's something I need to discuss with my team.

I will indeed submit a feature request.  If I were to keep current with your tools and migrate from DataSocket to Network Variables, it would require adding in an extra layer of seperation (DSC), plus all the costs, extra configurations, troubleshooting and license management that go along with that.  If Network Variables could directly communicate with OPC it would make Measurement Studio a much more attractive option for those of us creating HMIs for industrial networks with a mix of hardware vendors & protocols.  Isn't OPC - conecptually speaking - really just another "network variable", running in a different process?  It seems like a perfect match to me.

Thanks again for your input,

Derrick Dunne

[drohacek]

Derrick -

Thanks for your feedback on this issue; it is very helpful.

Out of curiosity, which user interface controls are you considering using to build these HMIs, the WindowsForms controls or the WebForms (ASP.NET) controls?

Also, do you plan to use any NI hardware in these systems, and if so, which?

David Rohacek

[ddunne]

Hello David;

For my immeditate needs, I plan on building a Windows Forms application.  However, I am also about to embark on a 3-year R&D project which would have mixed Win & Web.

With the immediate need, there is no NI hardware - hence my interest with compatibility with OPC (then I could easily mix vendors).  With the 3 year project, there may be opportunity to use NI hardware.  Our sensor requirements are pretty trivial (mostly dry contact, some analog), and to date we have been focusing on PLCs & ethernet based remote I/O.  Our biggest goal for our software is to be flexible with the types of hardware it can support - again, hence our interest in OPC.

Derrick

[drohacek]

Derrick -

I spoke to some other people here, who are more directly involved in the decision-making for the underlying DataSocket components, about whether we will have 64-bit support for DataSocket. I was overly pessimistic about this issue. They seem to think that it is likely that we will create a 64-bit version of DataSocket.

We are also actively discussing future options for support for more directly accessing OPC variables from the Network Variable API, but I do not have any more specific information to give you at this time.

Thanks for all of your input.

David Rohacek
National Instruments

[drohacek]

I should clarify one of my above statements a little bit.

The statement:

"They seem to think that it is likely that we will create a 64-bit version of DataSocket."

Should have been:

"They seem to think that it is likely that we will create a 64-bit version of DataSocket for the purposes of supporting OPC (as opposed to DSTP)."

David Rohacek

National Instruments

[ddunne]

Thanks for the updates David.  All very helpful information!

Derrick

[Abhishek Ghuwalewala]

The following Knowledge Base article explains the procedure for using the DSC runtime for binding OPC items to the Measurement Studio Network Variable class library:

http://digital.ni.com/public.nsf/websearch/599A1CAE18B7048F86257248005941F9?OpenDocument