The first-ever XML Symposium drew a large crowd at the Anaheim Hilton. (All photos by Frank Capuano, Strata Resource Inc.)
ANAHEIM, Calif. - "Structured text designed for communication between machines." Sounds simple enough, right? That's XML (eXtensible Markup Language) as defined by Alex Chervet of Echelon Corp.

Chervet was one of several presenters at the first-ever XML Symposium 2004, sponsored by the Continental Automated Buildings Association (CABA) and Clasma Inc. The daylong tutorial on XML, held at the Anaheim Hilton on Jan. 27, was held in conjunction with the 2004 International Air-Conditioning, Heating, Refrigerating Expo. Chervet tackled the task of explaining XML basics.

He proposed what every presenter supported: Not only is XML a language for machine-to-machine (M2M) communication, but it is becoming the language of choice and could be the gateway concept to realizing open systems on an unprecedented scale.

As pointed out by Chervet, advantages to XML include the fact it cannot be owned. It is designed for M2M but is quite readable by humans. It is optimized for travel over the Internet and is a common tool in that sector, he said. It allows computers to request pages from servers without human intervention (as opposed to HTML, the popular Web page language based on human interaction). It works with any computer, it meshes well with the open-source movement, and it can translate easily to spreadsheets, noted Chervet.

Chervet did admit that conventional wisdom also suggests the XML is the perfect "Trojan horse," where proprietary system manufacturers could be tempted to "slap an XML interface on a portion of the system and claim to be open." Also, it works best only if the participating devices use the same XML terms for types of equipment and data services, and for security, noted Chervet.

The panel on XML-related HVAC industry initiatives featured (from left) Paul Ehrlich, chair, oBIX; Barry Haaser, executive director, LonMark International; Jim Lee, president, BACnet Manufacturers Association; Mark Palmer, Fiatech; Wayne Dunn, ASHRAE, and John Kennedy, aecXML.

There's The Rub

The panel on XML-related HVAC industry initiatives featured industry firepower across the board. Paul Ehrlich, P.E., is the chair for oBIX (Open Building Information Xchange), a 110-member collaborative industry effort to reach such consensus XML definitions. Ehrlich is also a Business Development Leader with Trane's Global Controls business.

"The needs of facility managers have changed rapidly over the last several years," Ehrlich said. "No longer are facilities seen just as a cost center, but rather as an asset that must be properly managed. To manage this means pulling together information from HVAC systems, fire alarm, electrical distribution, security, and other systems. These, in turn, need to seamlessly integrate with each other, as well as facility and enterprise management systems," such as SAP and Oracle.

"Too many vendors are using XML in nonstandard ways," concluded Ehrlich.

In truth, oBIX - for good or bad - is not alone in working on the task at hand, and multiple opinions exist about the path to harmonious XML implementation.

Barry Haaser, executive director of LonMark International, outlined his belief that LonMark's strengths will turn out to be a natural complement to oBIX, providing a "real solution" to achieving what Ehrlich called "system-level data sharing."

An alternate perspective was offered by Jim Lee, chairman of the BACnet Manufacturers Association, and president and CEO of Cimetrics Inc. The HVAC industry product cycle tends to work slowly, he reminded the room, and it doesn't synchronize with other industries' movements. He pointed out the work already done by the BACnet XML committee, plus the BACnet infrastructure and core technologies already in place. He supports taking the ISO path to XML standardization and espouses a more tempered pace for the standards process.

John F. Kennedy, of aecXML, and Wayne A. Dunn, P.E., chairman of ASHRAE's XML Code Guideline committee, also outlined the work their respective groups continue to do. The aecXML agenda involved needs and definitions for particular building systems, presenting itself as the "central location for AEC-focused" schema promotions and specialty definitions needed by a bevy of related businesses. Dunn's committee, also taking a clearinghouse tack, looks to republish definitions as set by various other groups and organizations, with a first market review slated for January 2005.

Mark E. Palmer of the FIATECH consortium rounded out the panel. His group's AEX (Automating Equipment Information Exchange) Project has reportedly developed freely available XML schemas to "support information exchanges required to specify, purchase and operate equipment, starting with centrifugal pumps and shell-and-tube heat exchangers."

Alex Chervet of Echelon Corp. presents the session titled, “XML 101 — What are XML and Web Services?”

Plenty Of Faith, Too Many Visions?

Following the panel's presentations, one attendee asked what XML means for contractors and engineers. Dunn replied that XML becomes valuable in data transfers between engineers' applications, and in sending data from design engineers to contractors who might bid on a project. "XML will allow more intelligence to be put into that information," he said.

Later in the afternoon, Tridium's Ed Merwin emphasized that used well, XML can serve to "extend the life of existing systems" and to provide more choice, allowing facilities to "choose best-of-breed (devices or systems), irrespective of vendor."

Mike Donlon, research and development director for Computrols Inc., reflected the speakers' notably uniform and sincere belief in XML's potential: "I truly believe, in my heart, that this will be the final step ... to bring [different building systems] all together."

XML may one day become be the missing link to saving time and transforming building efficiency on a widespread scale, but the final consensus was that true agreement on standard XML definitions has to be reached first on an industry-leader scale. Ironically, with several well-qualified groups each working toward establishing the dictionary for XML usage, reconciling the efforts of the aspiring standardbearers may spell short-term difficulty for a language poised to transform building systems.

Final Note

The board of directors for CABA announced it would begin the process of transferring governance of oBIX to a newly created technical committee at the Organization for the Advancement of Structured Information Standards (OASIS). OASIS is a global, nonprofit consortium that focuses on the development and adoption of e-business standards. Along with the transfer to OASIS, oBIX announced the formation of a technical committee to continue driving progress on the specification.

"We are pleased to have nurtured the formative stages of the oBIX initiative," said Ron Zimmer, CABA president and CEO. "We expect that the shift to OASIS will eventually accommodate the creation of a complete Web services specification devised specifically for the large building sector."

Comprised of representatives from the entire spectrum of the buildings system industry, oBIX includes professionals from security, HVAC, building automation, open protocol, and IT disciplines. OBIX was originally established as a CABA working group in April 2003. Today its membership has grown to over 100 members. CABA will continue to be involved in oBIX and said it is pleased to be recognized as its founding association.

"CABA's contribution to oBIX encouraged broad industry support for the initiative," said Ehrlich, chair of oBIX. "It is our intention to continue the momentum required for a robust and operationally effective standard."

The object of oBIX is to have a common, standardized, secure way to manage intelligent buildings with greater interoperability between systems. To achieve this goal, oBIX is creating standard XML and Web services guidelines to facilitate the exchange of information between intelligent buildings, enable enterprise application integration, and bring forth systems integration.

Based on standards widely used by the IT industry, the oBIX guidelines are de-signed to improve operational effectiveness, giving facility managers and building owners increased knowledge and control of their properties. Eventually, oBIX aims to transform the guidelines into a standard protocol for building systems, a core piece of the work that will be addressed in the OASIS technical committee.

Beverly is editor of Engineered Systems, a sister publication of The News.

Publication date: 02/23/2004