Group's generic model to blend ISA 95, OAGIS standards

An industry coalition looking to blend two standards for the integration of plant-level data with enterprise systems will have a generic model that supports this convergence ready by May 2007. The Manufacturing Interoperability Guideline Working Group (MIGWG) looks to unite the ISA 95 standard overseen by ISA with a similar portion of the OAGIS standard from the Open Applications Group (OAGi).

Speaking at the ISA show in Houston in mid-October, Keith Unger, a principal manufacturing IT consultant with Stone Technologies, a St. Louis-based systems integration firm, says ISA 95 is widely used in the process and batch industries, while OAGIS is used in discrete verticals such as automotive.

"We have a goal of developing a model that's generic and applies to all industries," says Unger, a member of the ISA 95 committee and MIGWG.

Unger says the generic model will serve as a guideline for making the standards more similar, which should lead to greater consistency in the way that plant-to-enterprise integration is done across verticals.

But rather than create a third standard, says Unger, the generic model will be a demonstration model that the standards bodies can use to make standards more similar, building on existing strengths. For example, explains Unger, ISA 95 uses common-sense terms for the points of integration between plant and enterprise, but lacks some of the detail for discrete manufacturing steps covered under OAGIS.

"For instance, maybe [ISA 95] needs a very detailed work-order routing model that we don't have in the traditional mixed-mode and process industries environments," says Unger.

Unger says the ISA 95 standard does have a couple of ways to add custom properties to handle additional points of integration, but believes the ISA 95 standard will gravitate toward including more standard properties. The working group's generic model should help "extend the standard part of ISA 95 that is missing," adds Unger.

The working group is using Business to Manufacturing Markup Language (B2MML)—an eXtensible markup language (XML) schema that implements ISA 95—as a means of mapping out differences between ISA 95 and OAGIS. This mapping and gap-analysis work is progressing on pace to devise a generic model by May 2008, according to Unger.

In other standards-related news from the show, Dennis Brandl, a manufacturing IT consultant and ISA 95 committee member, says B2MML will be updated by early 2007 to support the "Part 5" transaction-handling definitions being added to the ISA 95 standard. B2MML already is being supported by vendors at both the plant and ERP levels to describe the common terms and categories of information exchange laid out in Parts 1 & 2 of the ISA 95 standard. The XML support for Part 5 will boil down to adding "verbs" such as "get" or "process" to the Parts 1 & 2 XML schemas, Brandl adds.

Tom Burke, president and executive director of the OPC Foundation, says vendor support for the foundation's OPC Unified Architecture (OPA UA) is building rapidly. By spring 2007, he says, all the major process control and industrial automation software vendors will have new products that support OPC UA, a series of specifications that use Web services and XML as the basis for moving data from the plant floor to the enterprise. Previously, OPC communication specifications were built around Microsoft technologies such as the Component Object Model, or COM.

Among other benefits, says Burke, OPC UA should make it easier for companies using industrial automation software architectures from vendors such as Wonderware and Rockwell Automation to tie in control systems or devices from third parties with their vendor architecture of choice. However, OPC UA is not meant as a replacement for the plant-data modeling performed in vendor architectures.

ISA will begin making its standards free to members, and increased its standard-related funding to make up for the elimination of fees. Beginning Jan. 1, 2007, ISA members will be able to download (in .PDF form) any ISA standard for free.