Our local newspaper reported that the local phone company had completed installing fiber optic cables between their central offices in the Boston area. That didn’t surprise me, but what did was the description of the cables they were installing. Each cable had 864 fibers in it!
The fire alarm systems industry has changed considerably over the years. Many old-timers can remember a fire alarm system that only detected a fire and sounded an alarm. Nonfire alarm systems did not interface with these fire alarm systems.