How low is "low cost?"
There is nothing fundamentally wrong with this kind of compromise; after all, "low cost" and "high reliability" are relative phrases. How low cost is "low cost?" That depends on who the customer is. Let's say that a particular wireless technology would cost $100 per node. That is prohibitively expensive for a light switch targeted at consumers in home environments. But $100 may be quite acceptable, perhaps even down-right attractive, for a customer designing an industrial process automation solution for factories.

Comparing low cost and high reliability provides only one example of the many concessions that have to be made when designing a wireless system, but it effectively illustrates the challenge. It is not clear why anyone thought that there must be a grand unifying wireless technology.

The unfortunate initial response to this reality, however, was the proliferation of a multitude of WiEC technologies, each promising to deliver what none of the others could.

The list is a veritable collection of trademarks, brands, and clever marketing: ZigBee, ANT, Z-Wave, INSTEON, Wavenis, ISA SP-100, WirelessHART (to name a few), and a host of other proprietary RF technologies from companies like Cypress, Nordic, TI, and Freescale (and many, many more). Each believes that they can build a better widget. It is worth noting that not all those technologies target the same markets, but many of them overlap.

The consequence is a market that is highly fragmented. Customers have a multitude of WiEC technologies to choose from, but no clear winner has emerged. Some customers are in a holding pattern, unwilling to invest in technologies that may eventually disappear because of lack of adoption.

The problem is that this has become a self-fulfilling prophecy—lack of adoption is feeding uncertainty, which in turn leads to lack of adoption. This has also meant that profits have been largely absent for a large number of suppliers. What little money customers are willing to commit to cutting the cord on their applications is being spread too thinly amongst too many suppliers.

Good news
The good news is that this kind of pressure is exactly what is needed to narrow the field down, and allow the more competitive technologies to float to the top. The principle of natural selection is in full-swing.

Already, the market is observing a growing maturity from these technologies, at least when it comes to the promises being made. The hype is slowly dying down, and is being replaced with rational, measured thinking that is based on sound engineering.

The new thinking addresses the fundamental flaw in the hype: A single technology cannot solve all problems equally well. But, it may solve a subset of problems extremely well.

A light switch and a valve in a factory may both benefit from a wireless connection but perhaps not the same type of wireless connection. By better understanding target markets and end applications, suppliers and promoters are fine-tuning their focus and their offerings.

Take ZigBee for example, the mesh technology that promised to be in everything from ultra low-cost consumer applications to mission-critical systems in factories. More recently, the ZigBee Alliance has been focusing on a few select applications that play to the strengths of ZigBee, including Automated Metering Infrastructure (AMI) and commercial building automation.

There is less talk now about consumer applications (where low cost needs make ZigBee less competitive than other technologies) and process automation (where higher reliability and stronger security are needed). The ZigBee specification continues to evolve (most recently with addition of the ZigBee PRO Feature Set) to address the results of real-world issues faced by customers who have attempted to implement ZigBee systems over the past two years. Compatibility between the evolving versions of the specification remains a challenge for both suppliers and customers.

The inability of ZigBee to address the industrial process automation market has resulted in some spin-off technologies. Designers have realized that the RF transceiver technology underlying ZigBee, defined by IEEE 802.15.4, may be the right transceiver for the task if paired with a networking protocol better targeted at challenges specific to process automation.