A perfect, straight line sloping gently downward is a perfect cable. Unfortunately, perfect cables rarely exist in the real world. Instead, you will see five distinct "events."

This looks like someone took a step down on the graph.

Elias nodded, plugging the ruggedized laptop into the access panel of the dark fiber strand. He opened the software. It was a specialized tool, an interface that turned invisible pulses of light into a map of the physical world.