[FroshKiller]

I thought "dark fiber" meant unused fiber. How can it be dark if you've got services running over it? Is there some other meaning in this context?

[bayindirh]

I used the term "dark" as in unshared, and as a result, you use it the way you like it.

Also, the term looks like it has both meanings.

Having a "dark fiber infrastructure" means having a web of unconnected fiber cables point to point, but since you connect your own devices to it, you don't have to share it with others.

As a result, its presence and its state is only known to you (i.e. it's in the dark).

I understand that my usage is not completely true, but in that context, it's not a flat-out blatant mistake either.

[rincebrain]

It's also not uncommon - people often describe big tech using dedicated lines they didn't lease from people as "dark fiber".

[FroshKiller]

I understand better now, you are really applying "dark" to the infrastructure (which happens to have fiber-optic cable) rather than to the fiber itself. The infrastructure is figuratively dark, and the fiber is literally lit.

[obivatelj]

Usually, dark fiber means that you got that cable (with one or more hairs) completely for yourself, as a customer. It is not leased line, you are not sharing it, it is your fibre to communicate with. It is more expensive, for sure, since Carrier could make lot of $$ out of it (many many Internet Customers for example), but at the end of the day it is cost efficient actually since you have no other interference on your cabling. You do not share bandwith, you do not share services, you decide about your techonlogy at the endpoints (GBICs, etc.).

[jbverschoor]

I think you got your definitions mixed up.

Even the name means: "it's dark, no light, as in no data, because that's what light is in this case"

[freshpots]

https://flexnetworks.ca/what-is-dark-fibre-why-would-i-want-....

It has two meanings. I have heard it most commonly used in reference to private fibre networks.

[jmbwell]

It’s dark in that the entity who purchased and installed it is not yet using it. Telcos install big multi fiber bundles, then actually use only a few strands. The rest are dark, waiting for growth or expansion or to be used as backups. You can lease those and light them up yourself until the telco needs them back.