I recently read an article that talked about "wireless standards craziness," referring to the frustrations of users dealing with multiple wireless networking standards within the context of issues like network management, interoperability, and security. My first thought was that we've been here before. The fieldbus wars of the 1990s were a free-for-all among vendors and consortiums trying to promote their own standards and protect their technological investments. During this frenetic period, more than 120 different protocols were developed and deployed. Everyone knew the performance specifications required to meet user needs. The issue was whose approach would win out.
The question today is: Have we learned from that experience? Wireless networking has gone through a period dominated by proprietary specifications, but the duration of this phase was relatively short. The lessons learned during the fieldbus wars regarding the value of open standards moved the industry much more quickly to the stage where standards bodies developed protocols for specific types of wireless networking applications.
To help focus these efforts, the Institute of Electrical and Electronics Engineers (IEEE) has guided the standards-making process by designating coverage zones for wireless networks. These include wireless local area networks (e.g., WiFi), wireless personal area networks (e.g., ZigBee and Bluetooth), wireless metropolitan area networks, and wireless wide area networks.
While the efforts of the IEEE would seem to clarify the situation, the technologies developed for particular zones of coverage can cross over into other zones. This blurs the lines separating the areas of coverage and complicates the situation by adding more variations to the mix.
In addition, industrial networks operate in extremely complicated settings. On any given plant floor, you'll find sensors, actuators, controllers, switches, and computers that are all connected with operational software throughout the infrastructure. The needs and types of connectivity required vary from level to level.
In response to the challenges posed by this complexity and to the need to maintain momentum, the industry has formed a committee made up of individuals who have grown savvy as wireless technology has matured.
Once More Into the Breach
On February 17, ISA announced the formation of the SP100 committee, whose mission is to "create standards, recommended practices, and/or technical reports to define procedures for implementing wireless systems in the automation and control environment at the field level." To meet the complex and varied needs of industrial networks, the committee hopes to come up with a hierarchical wireless industrial standard built on levels targeted at differing industrial requirements. Hopefully, the work of SP100 will move us closer to a set of wireless standards that we can live with.
Efforts to create functional wireless networking standards have benefited from the lessons of the past—to a degree. But no matter how you cut it, the process is not going to be quick or easy.