H. Michael Newman, chairman of the BACnet XML Working Group, points out some of the advancement with the BACnet standard.
ANAHEIM, Calif. – When the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) published its BACnet standard almost 10 years ago, former committee chair Mike Newman stated, "We are on the threshold of new possibilities of designing and operating buildings and for new applications that have not even been thought of in the market."

That remains true today.

As BACnet is increasingly being deployed around the world, its capabilities also are expanding through the continuous maintenance of the standard. On Tuesday at the Anaheim Convention Center, three prominent people involved in BACnet's creation briefed the trade press regarding new advances with the standard.

In addition to Newman, who is now chair of the BACnet XML Working Group, other speakers included Steve Bushby, current chair of ANSI/ASHRAE Standard 135 (SSPC 135) committee, and Jim Lee, president of the BACnet Manufacturers Association.

"A lot has happened since the original version of the BACnet standard was published in the summer of 1995," said Bushby. "A lot has happened since then both in terms of new capabilities being added to the standard and in the realization of those features in BACnet products installed around the world."

Newman noted that some more changes are coming in the near future related to the use of XML and Web Services technology.

"BACnet's chore is its ‘objects' and ‘services' model," stated Newman. "The objects allow the functionality of building automation and control system devices to be unambiguously represented. The services allow communication between devices related to their functionality. In addition, BACnet prescribes a variety of wide- and local-area internetworking solutions."

Newman said BACnet's biggest strength is its ability to evolve and embrace new technologies as they become available, "thus enabling it to meet the ever-growing needs and expectations of building owners, operators, and users."

An example of this development, said Newman, was the creation of BACnet/IP several years ago. This enabled BACnet messages to be sent over the Internet.

"Today our industry is abuzz with the possibility of integrating building automation and business systems in such a way as to create valuable new services for the building owner," said Newman. "In an attempt to find a common language between systems, SSPC 135 is deliberating the addition of the information technology (IT) known as ‘Web Services' to the BACnet standard.

"Web Services is a set of technologies that enable ‘machine-to-machine' communications, using two standards called XML [eXtensible Markup Language] and SOAP [Simple Object Access Protocol]."

According to Newman, among the design objectives for this new capability include:

  • BACnet /XML must support Read, Write, and Find Device capabilities at a minimum. "Support for advanced services can be added as the need is demonstrated," he said.

  • BACnet/XML must leverage the extensive capabilities of the BACnet standard and the work of the BACnet XML Working Group.

  • BACnet/XML must be compatible with industry standard IT security mechanisms.

  • BACnet/XML may enhance BACnet services where appropriate.

  • BACnet/XML must support the connection of systems through Network Address Translation devices and firewalls.

    "The use of XML to represent BACnet messages will permit ‘Web Services' gateways to provide building automation data to ‘enterprise' systems in a new way," said Newman. "At the ASHRAE 2004 Winter Meeting, a small group was formed within the XML-WG to develop a Web Service that will use a hierarchical naming method to identify building information that can then be used in business applications, reports, and spreadsheets.

    "The service will also allow searching for, and modification of, building data by appropriately authorized users. The service will be structures in such a way as to permit its application to other building automation protocols that may be present."

    He admitted that BACnet and other protocols – such as LonMark and CABA/oBIX – are not formally working together, "but many of the participants in the oBIX work are on the respective BACnet or LonMark committees.

    "The oBIX agenda seems to be in a state of flux, so it is not yet possible to determine potential conflicts," said Newman.

    With the 2004 ASHRAE Winter Meeting taking place this week in conjunction with the International Air-Conditioning, Heating, Refrigerating Exposition, Bushby said it was the committee's hope to deliberate, approve, and put through about 130 proposed additions to the standard through the public review process.

    "These ideas were combined into six addenda that have already been published and three more that will be approved for publication this week," he said. "I wasn't to focus on the three new addenda that are on the Board of Directors agenda for approval this week."

    Look for more regarding the upgrading of BACnet in a future issue of The News.

    Publication date: 01/26/2004