Open systems: The foundation for a new era of BAS
Dividing the vendor roles
An open philosophy sets the stage for vendors to focus on their area of expertise and work with other providers to deliver a complete solution, one that allows building owners to select the right products and vendors for their needs. In this strategy, the integrator role is elevated to oversee the complete project and ensure the building owner's objectives while separating the vendor roles so no one vendor is supplying the entire solution. Many building owners have implemented a multi-tier system architecture that defines these roles, where tier one is the sensor/actuator level; tier two is the field devices, such as the controllers; tier three is the in-building communications and connectivity level including device communication protocols; and tier four is the IT and enterprise infrastructure including user interfaces, both local and remote, data collection, and analysis. By utilizing the four-tier model, a check-and-balance system is put into place that ensures fully transparent interoperability throughout the system.
The proliferation of IT into nearly every aspect of our daily life illustrates just how efficient and productive we can be with data readily available to us. The BAS industry is no different. As building owners discover what it means to have an open system, they see how intelligent decisions based on usage data positively impact the bottom line. While the definition of "open" may differ from one person to another, the common thread is data and its level of interoperability and accessibility. Couple this with an open protocol that facilitates the access to data across different systems and platforms, and this opens the door for the facility and IT departments to cooperate in the design, implementation, and management of the BAS.
Access to data from anywhere requires even greater support in the base system specification. Tying a BAS system into the facility IP network may seem simple and straightforward, but as soon as the IT department gets involved, a host of issues become exposed as the BAS system encroaches into the IT space. More and more control devices feature native IP access ports, requiring a fixed IP address. The IT department must be aware of and prepared for increased bandwidth utilization and, of particular importance, the security risks.
In 2004, the U.S Army Corps of Engineers published the Unified Facilities Guide Specifications, a definitive specification guideline that identifies building and integration requirements with the ultimate goal of creating "one integrated, multi-vendor system with no future dependence on any one contractor or controls vendor." The guideline encourages competitive bidding at all levels of procurement, and it has been adopted by thousands of installations nationwide. According to Will White, lead project engineer for the U.S. Army Corps of Engineers, "Security on our building systems is critical, and we are actively and aggressively defining the systems and standards to ensure the highest level of security is enabled. This may put an additional burden on the integrators and their vendors, but will enable us to expand our strategy into a fully enterprise-based solution rather than the current, single-premise-based solution."
Efforts within several standards groups are engaged in defining the hardware and software requirement for various levels of security. SGIP 2.0, Inc., is providing a national framework for coordinating all Smart Grid stakeholders in an effort to accelerate standards harmonization and advance the Interoperability of Smart Grid devices and systems, including security issues for tying the smart building into the Smart Grid. Other organizations, including LonMark International, ASHRAE, OASIS, and others, have developed security task forces to begin addressing the specific issues faced by building automation systems.