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Re: New forum topic - Open Control
Feb 13, 2002 3:40 pm, by Greg Goodman
Text :
>> "I think that most people will want to buy something which is already put
>> together and tested by someone else.
> My understanding is that what Michael describes is the definition of a
> proprietary system.
I disagree completely. "Proprietary" means that only the manufacturer has access to the internals, or the right/ability to fix or modify it. Michael is describing a product whose components are open, but whose initial assemblage and configuration and testing have been taken care of for you. When you buy such a package, you're paying for the effort and expertise that went into the packaging. You're not paying for the software, and you're not obliged to get your support, or your fixes, or your consulting, or your upgrades and add-ons and customizations, from the same provider. "Open" means you have the right and the access (whether or not you have the skill) to take over completely the management and maintenance of your system. Lacking the skill or the time or the inclination, you are also free to have someone else do it.
To use a mundane example, houses are "open" technology; the plans are published, the materials are readily available, and any technologist competent in the field can build one, or fix or modify one once it's installed. That doesn't mean that everybody builds their own house, or that there's no money to be made building houses for other people. What it does mean is that there are a variety of approaches to getting a house built. You can buy the materials and build one, or buy the materials and pay someone else to build one, or pay somebody else to take care of the whole thing. You are also free to buy a pre-fab that only the manufacturer can work on, but that's an idea that even Buckminster Fuller had trouble selling to the public.
The analogy can actually be pushed a bit further. A house has a number of complex subsystems, and any one person is probably not an expert in all of them. You may be a good carpenter or plumber or bricklayer, but
you may not know much about pouring concrete or wiring electricity. For this, you hire specialists, or hire a general contractor that employs specialists. Later, when you need the attic converted to a bedroom, or an alarm system installed, or a swimming pool that ties into your
plumbing and electricity, you're not beholden to the original builder.
As Curt frequently points out, "open" isn't just about low cost; it's about freedom. And that freedom isn't limited to the choice between doing it yourself and buying from one of the big-name distributors. It's a freedom that lasts forever, and survives the demise of the manufacturer, survives the abandonment of software packages by the provider, is immune to the obsolescence of standards and protocols and interfaces. As long as you can find (or be) someone competent in the technology, you can protect your investment.
> I can't think of anyone I have ever known, that would go
> to the trouble of organizing, testing and distributing this software without
> a payback.
The payback for packaging is a completely separate issue from whether "pre-packaged" is equivalent to "proprietary".
There are two easily identified revenue streams from packaging/distributing open source components:
1) people paying for the convenience of using your packaged version
red hat makes money from their distributions because most linux users don't want to collect the several hundred software packages it takes to make a usable desktop box, verify that the versions are current and correct, compile them in an appropriate development environment, and configure them from scratch. users are also happy to have the correct video driver (out of the several hundred possibilities) auto-selected and installed, the correct NIC driver, the correct ATAPI/CDROM driver, etc. red hat (and every other distribution provider) has done sufficient work that the dollars it costs me to buy their distribution (about $30) is much less expensive than the time it would cost me to accomplish the same thing (many hours, maybe days).
2) people paying for support
which brings us to your next point.
> ... the moment anyone
> but the distributor touched the code ...
> therefore destroying the foundation of "tested by someone
> else", the distributer has every right to cease supporting the software or
> charging plenty to fix it.
True; that's what warranties, service contracts and support agreements are for, which is a topic for another posting.
Regards,
Greg Goodman
Chiron Consulting
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Re: New forum topic - Open Control
Feb 14, 2002 2:00 pm, by Bob Pawley
Hi Greg:
One of the postings had this statement -
"That's where distributions come in - they're the sales departments of the Linux world, and that's where you go when you want a structured, organized package.
One can modify anything in Linux, but one rarely does. Indeed, I would expect that a plant would standardize on a particular combination of
packages from a particular distribution, perhaps customized, and then refuse to change a thing for years (without good reason). Only the actual
control logic would change"
I am still not convinced of the difference between a Linux package that a distributor puts together that "no one can touch" and a proprietary package, an original invention, that has the code protected. I agree that with Linux
you do have the option of changing the base code at any time. But, there are consequences of doing so, such as:
- warranty violation
- creating a non-standard format
- by definition you force people, newly exposed to any Linux installation to review the whole software package
- changing a "standard" software package can inhibit standardizing solutions across processes, plants and the whole enterprise.
These consequences all come at a cost that has to be calculated before adopting any open source system.
I would further suggest that trends in the software industry as a whole, automation always lags, is to make tools easy and intuitive to use. People want tools - the vast majority are not particularly interested in doing the coding. An example of this trend can be seen from the explosion of computer sales once Microsoft moved from DOS to Windows.
I agree as well, that proprietary software for systems needing flexibility, such as industrial primary and advanced control, is restricting. However, I have yet to be convinced that a purely open source system is the way to go.
Bob Pawley
www.automating-automation.com
250-493-6146
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Re: New forum topic - Open Control
Feb 14, 2002 9:50 am, by Alan Brause
Your house analogy is well taken and goes a long way to clear up some of the misunderstanding about "open" technology. But the problem I see is that home building is described in sets of established codes and automation isn't.
For instance, every lumber manufacturer knows 2X6 dimensional lumber is used in building, every electrical manufacturer knows if they build to UL specs they can sell their products, every plumbing
manufacturer builds fixtures that connect to standardized pipe sizes, you start to get the picture.
Where are the codes and standards in automation that can allow this type of open technology to work? Isn't this where it all has to start?
Alan Brause
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