[throwawaysea]

For someone unfamiliar with all these technologies and terms, do you mind explaining in a simpler way? What’s OTDR or DF? What do you mean by “build to you”?

[millzlane]

https://en.wikipedia.org/wiki/Optical_time-domain_reflectome...

OTDR basically uses light to measure a fiber cable's performance. A lot of these devices have break locators in them.

and DF I imagine OP is talking about dark fiber. https://en.wikipedia.org/wiki/Dark_fibre

[bifrost]

Yep, you got it!