Commentary: What makes a system open?

Calling an industrial wireless system “proprietary” or “closed” is a marketing kiss of death. But do we agree as to what “open” architecture really means?

By Control Engineering Staff November 5, 2008

In our recent Webcast, Wireless for Bridging Applications , (now available for on-demand listening) one participant claimed another’s wireless system was an “integrated but closed architecture.” While we avoided fisticuffs on air, it did prompt me to consider what makes a system “open” anyway?

“Closed” and “proprietary” are bad words when describing anything that requires connectivity, so let’s look at some of the attributes of open systems. I asked two individuals what they think makes something open: Jeff Becker from Honeywell Process Solutions (who’s wireless system was maligned in the Webcast) and Ron Helson, executive director of the HART Communications Foundation , a group that is founded on interoperability.

Jeff Becker: “Open systems may be one of those terms where different people may have different interpretations. When I talk about open systems in the context of computer systems, I am referring to using well-known and widely deployable system interfaces that allow for interoperability with products from other vendors. The advantage of open systems to users is that they can integrate and combine elements of a system from different vendors, which prevents vendor lock-in. There is also a larger talent pool available that knows how to work with these interfaces. This ultimately lowers cost and improves choices through competition.

“There is an advantage for us as a vendor as well, since the interfaces are well defined, we can focus our efforts on the elements of the system that differentiate the product, rather than spending resources on interfaces. For example, rather than having to design a wired interface, I can buy Ethernet chips and software from many vendors, and have a large pool of talent that already knows how to use these elements. So open systems provide advantage across the value chain.

“I would consider OneWireless an open system. It uses well known and widely deployed interfaces like Ethernet, WiFi, and Modbus. It passes IP traffic across the mesh in conformance with IP networking standards, and can be managed with network management tools that use typical SNMP protocols. We make our sensor radio hardware and software available to any vendor at reasonable cost today, and we are migrating towards ISA100 Standard sensor interfaces in the future. Any vendor can therefore design a product that will work with our system, and any user can buy products from multiple vendors for use in their OneWireless network. I believe OneWireless is the most open industrial wireless system on the market today.”

Ron Helson: “The HART Communication Protocol (which includes WirelessHART) is an open communication technology. An open technology is one that is not owned by one company, but is openly available to anyone who wants to use it. The HART Protocol standards are well documented and available to anyone who wants them, regardless of whether they just want to understand the details or they want to implement the technology in products. The HART Protocol became an open communication technology in 1990, and the HART Communication Foundation was founded in 1993 to establish and administer programs that ensure the technology remain openly available for the benefit of industry.

“The HART Communication Foundation provides a full range of services to support the technology and ensure the compliance of products around the integrator, end user, educational institute, government agency) interested in use of the HART Protocol technology can and should join the Foundation.”

So, as we apply this to the growing world of wireless communication, “open” suggests more than just the ability to buy compatible equipment from more than one supplier. It begins with an intentionality to create the best for the supplier and user, allowing both to benefit.

—Peter Welander, process industries editor, ,
Process & Advanced Control Monthly
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