OPC no longer an "Open" standard?

[Wilhelm Medetz]

OPC has always been and 'Open' standard and also still claim to be an 'Open' standard (s. a. 'What is OPC?'
http://www.opcfoundation.org/Default.aspx/01_about/01_whatis.asp?MID=AboutOPC).

But the official OPC download policy has changed.

The only public downloadable OPC specification nowadays is "OPC UA Part 1 - Concepts RC1.20 Specification". All other specifications (e. g. "OPC DA 3.00 Specification") are only available to OPC members.

I also received the following E-Mail from OPC confirming this new download policy:

[Randy]

Here is an explaination of the new policy provided by Tom Burke:

In the early days the OPC foundation actively promoted and encourage adoption of the OPC data access technology without caring who and how implemented the technology, or how they evangelized the OPC technology through the delivery of their products. What we learned was that the end-user satisfaction was compromised by many vendor companies as well is end-users building OPC products that were less than satisfactory with respect to quality and also resulted in many interoperability problems with products that were developed and certified by the OPC foundation members.

The OPC foundation members of which there are a little over 400 of them now deserve better. The OPC foundation has a responsibility to making sure that the support burden by the OPC foundation member companies is significantly lowered as well is the perception of the OPC technology is of the highest quality. It is virtually impossible for the OPC foundation and improve the quality of products from nonmembers of the OPC foundation without knowing who the companies are that are not members of the OPC foundation.

We allowed anyone to download specifications from the OPC foundation based on the rules that we started the OPC foundation with. We frequently see client applications built on the OPC technology by nonmembers being essentially quickly developed and not using the technology in the most efficient fashion resulting in many interoperability problems.

We concluded that the OPC foundation had two alternatives with respect to improving the quality of products. One alternative was to require all companies to become members of the OPC foundation in order to use the OPC technology. This alternative would essentially raise the bar to make sure that it a company was going to use the OPC foundation technology as part of the rules of membership they would have to use it in such a way to clearly demonstrate secure reliable interoperability and quality products being developed and delivered based on the technology.

The other alternative was to actually require companies that were interested in using the technology but did not want to become members of the OPC foundation be required to pay a nominal fee to download the specifications accordingly. By knowing who the companies are we can do some things in a proactive fashion to make sure that the companies that buy the specifications build products that are up to the quality of the OPC foundation standard.

We looked at a number of the other standards organizations and quickly realized that either alternative was a feasible solution as many of the organizations do require membership in order to use the technology from the organization, and in other cases the organizations sell the specifications under the auspice of still being open. What we know is those organizations that sell the specifications basically sell the specifications in such a fashion that the reality is that it is better to become a member of the organization from a cost-effective standpoint from the companies that wish to just buy the specifications without becoming members.

We decided to restrict the downloads as part of our feasibility exercise with respect to the OPC foundation specifications to only members of the OPC foundation on May 1, 2006. We put in place plan is to build a shopping cart to facilitate nonmembers being able to purchase the OPC foundation specifications at a nominal fee.

We will be putting together a form on the OPC foundation web site that will allow organizations and companies to petition the OPC foundation accordingly to be able to evaluate the OPC foundation technology without purchasing the OPC foundation specifications or becoming members of the OPC foundation. We want to make sure that the products that are built based on the OPC technology are of the highest quality.

[Bhuvnesh Jain]

There may be pros and cons.

For a moment, if we agree with Mr Burke and consider that one should be a member of the OPC foundation for accessing the specification.

But the OPC foundation has a mebership fees structure which varies with the sales ($). The lowest slab here is quite comfortable for all develped countries-even for startup companies.

But what about the startup companies in developing nations. The amount $1000 is not justified and quite high. That's why you have only four-five companies registered from a country like INDIA.

Willing to became a member for two years, but waiting to grow till my company can afford....

[Thomas Burke]

My OPC Vision is to evangelize and have OPC adopted everywhere, and truly have vendors and end-users know that products based on the OPC technology are of the highest quality.

The OPC Foundation commitment is about providing the technology and specifications that "guarantee" secure reliable interoperability.

Working with all vendors and end-users to successfully adopt the technology and make the most effective use as always been the fundamental principle.

There are some other significant reasons to "require" membership in the OPC Foundation to acquire and use the OPC Foundation Technology, and I assure you they are all based on my mission to have OPC be the standard known for plug-n-play secure reliable high performance interoperability. Requiring membership gives us the opportunity to know who the vendors and end-users are and to work with all of them to deliver the highest quality products.

There are many member companies that have dedicated significant resources to the development of the OPC specifications as well as the technology that we as OPC and the OPC Members will be making available to the members providing the solid foundation for deploying OPC products.

I am currently investigating a number of alternatives to facilitate an equitable structure to allow all companies to successfully use the OPC Foundation Specifications and technology, and would welcome all thoughts and suggestions to facilitate widespread quality adoption of the OPC technology.

Thanks for "listening to my rambling thoughts"

Tom

[Wilhelm Medetz]

I completely agree with Thomas J Burke, that it should (even must) be a goal of the OPC foundation to “guarantee” secure and reliable applications.

But I believe that the chosen decision to restrict access to the OPC specifications has some very disadvantageous implications, both two developers and end users:

1) A software developer no longer has the possibility to analyze the specification in order to decide whether to develop a product based upon OPC or not. He even can not decide about the efforts necessary to adapt OPC technologies, whether to buy and reuse off the shelve OPC components or whether to develop the necessary interfaces himself. This is true, both for client and for server applications.

2) On the same side it is impossible for and end user to understand the implications (technological and quality) of using products based on the OPC standard (has he does not get the standard to read). He also has not chance to evaluate, whether an OPC based product, really adheres to the standard. He even has no chance to articulate his needs – like I want an OPC based product, fulfilling the following standard subset – as nobody will tell him that these subsets exit and which implications they have.

Thus I think restricting the access to the OPC specifications will heavily slow down the further widespread adoption of OPC, esp. of the new OPC-UA.

If the goal is to “guarantee” secure and reliable applications – it would have been much easier to define an OPC compliancy statement, which is bound to a formal test certificate from the OPC foundation. As it is now any OPC member can deliver OPC based product, but nobody certifies that these products are really OPC compliant – so there still is no real “guarantee”.

[Thomas Burke]

The OPC Foundation is evaluating opportunites to facilitate developers analyzing the OPC Specifications without being members.

Consider the following:

Many software companies do provide demo versions or products that expire after x number of days. But how could OPC provide a demo version or version of our products and specifications that expire after x number of days?

Some of the end-users have even suggested that a strategy be deployed where products cannot be sold unless they are certified, and at a minimum they are lobbying for best practices where they make their purchase decisions based on level of certification.

Some standards (specifically in the hardware industry), require the vendors to even license the technology and be required to use a component (chip) from the standard organization for every product they build. End user satisfaction seems to be significantly higher with the quality of produts that are delivered based on this strategy. I get chastised every day for not following the model of the hardware organizations, and requiring vendors to use OPC technology in their products.

How often can you evaluate and read a recipe book without buying it first?

What things can you borrow / evaluate before buying, and never really return?

OPC has had an open source model for members with our reference implementations(sample code), and the result has been many versions being shipped of some of the "standard" componets resulting in interoperability problems.

The majority of other standard organizations require membership or sell the specifications. OPC is working at improving the quality of the OPC deliverables, and want to improve the qualityof the products that are based on the OPC Technology.

So Here is my offer:

Any developer that does not want to be a member of the OPC Foundation but wants the OPC Foundation Specifications to evaluate the OPC technology, I will personally provide them unrestricted access to the OPC specifications as long as they provide complete unresticted access to any products they or their company has built in the last 10 years (matching the opc foundation 10 year anniversary) that I am alowed to provide to members of the OPC Foundaton for to evaluate and use for interoperability testing. Demo versions of products are unacceptable.

Developers also must be willing to bring their products to the Interopeability workshops and prepare for the grueling testing theat all OPC Foundation members go through to validate quality and interopaerability. See where I am going?

More to come....

[Thomas Burke]

My vision of OPC from an end-user perspective in simple, and I felt I should comment on the following to clarify and make sure the vision of OPC is understood.