Wireless Communications Standard

Posted January 26th 2011

Building managers that have been around long enough are likely very familiar with the evolution of communications standards. BACnet was touted as the ‘standard’ for many years before it actually approached that status. Various vendors each claimed to communicate over BACnet, but in reality it was still difficult to get systems to interoperate. BACnet has come a long way in standardization since those early days. However, now the building industry is contending with wireless standardization. This may seem like Groundhog Day for those that went through the hardwire standardization process.

Many people in the industry believe both the residential and commercial wireless standard will be ZigBee. Unfortunately, the development and adoption of ZigBee has gone through fits and starts, making it challenging for both vendors and customers to put a stake in the ground. Fortunately for the commercial building space, the prevalence of an existing communications standard (BACnet) provides a very solid foundation on which the wireless standards can mature.

Generally, the drivers for pushing towards a standard protocol include:

• Ensuring new systems can be easily and quickly integrated with existing systems
• Reducing the need to strand legacy systems
• Minimizing the required communications infrastructure
• Driving down costs with economies of scale

Since most legacy systems today communicate over BACnet, wireless systems can address the first two drivers by offering a BACnet interface from their hubs. This leaves only the last two drivers unaddressed. In regards to infrastructure, wireless has a light footprint by its very nature. Furthermore, a well designed wireless system would minimize the number of repeaters and hubs, making it less of a burden to have multiple wireless systems in the same site. The BMS would be able to synchronize the various systems centrally, achieving the desired performance demanded by the building manager. In regards to the economies of scale, vendors in the building industry can take advantage of the scale wireless has already achieved in other industries.

Generally, standards development is a classic chicken-and-egg problem. If vendors were to wait until a true standard developed before releasing products, then no standard would develop. With BACnet in place, vendors can confidently develop their solution without the risk of being stranded later. Building managers can likewise move forward without the risks that arose in the early days of BACnet. As a result, the adoption and maturation of wireless standards in the commercial building space should go much more smoothly and quickly than previous generations of communication technology.