Fiber Internet Hypothetical

Alright, so you talk about fiber and how it's all mostly there and all that needs be done is lay the "last mile" of it.

So my question posed in the form of a hypothetical wherein one has paid thousands to have fiber connected to their house, or bought a trencher and has done it themselves like Wendell mentioned.

What comes next? Do you call your local ISP and tell 'em you're now in the super secret fiber club and whisper 'swordfish' into the phone to unlock gigabit? Do you have to start your own ISP, or do you just sit on your hands, fiber ready, until someone offers it locally?