The Fragility Factor

E-mail Wayne Manges

The reliability of wireless systems has long been the Achilles' heel of the technology. Perhaps one of the first steps toward allaying the fears of users is to come up with a litmus test to gauge the system's vitality.

Will It Work?
Recently, I've been pushing a concept based on the word "fragility." It seems to me that most companies installing wireless systems need to know two things: Will they work now, and will they work later?

The "will they work now" part is included in the "can you hear me now" vs. "engineered solutions" discussion in my August Wireless & M2M newsletter essay. The "will they work later" part seems to me to be a function of the changes that occur after the original installation. If the only indication available to operators is a green light indicating up or down, the system appears to me to be quite "fragile."

We need to develop a way to let the operator know that the system is being stressed.

During a meeting of the ISA SP100 last month at ISA headquarters, I proposed that we install an algorithm that measures "fragility"—an indication of how far the wireless system is from failure. The basic algorithm would simply compare a current value of the system's performance with an expected value. If we can compare an expected performance value—say from a suite of models running in background—with an actual performance measurement, we would have a good indication of how close we are. The operator could then take action to prevent further degradation in performance and perhaps prevent catastrophic failure.

More Details Forthcoming
The concept of "fragility" may be the first step toward addressing one of the major concerns about wireless systems. To my way of thinking, it would benefit from further discussion by the members of the ISA's SP100 committee. Look for more details in the forthcoming months, and check out my account of the committee's activities in the September issue of Sensors' Wireless & M2M newsletter.