…across the walking path!
… rather use aerial optical cable, mounted 25cm/10in above the ground. Ideally paint it in same colour as floor. 
In case it’s unclear, the resulting damage wasn’t from tripping: it was merely from being trodden on occasionally. This cable was sold as bend-resistant plenum type, so I figured it’d put up with this abuse well enough. Nope. The stuff positively fell apart over the course of a year, resulting in the disintegration you see. I only learned of it when the link finally failed, sending me on a long troubleshooting process that involved SFP swaps, time spent staring at WinBox, and other fun.
Along with the replacement cable, I’ve ordered a set of floor cord covers.
Learn from my lesson, chillins!
I’ve guessed that much 
The rest was my sarcastic proposal on how to avoid similar damage next time 