[c-nsp] OT - Dark Fiber

[Justin M. Streiner]

On Wed, 2 Sep 2009, chris at lavin-llc.com wrote:

> I was curious to know if there are different ways to go about purchasing
> dark fiber. If you have Site A and Site B only a few miles apart and 
> you're happy to provide the light, how do you get the fiber? Not 
> expecting to obtain right-of-way/permits/ditch digger. Do you lease 
> (meaning paying a MRC) or is it 'purchased' (meaning a NRC)?

In a case like this, it's commonplace to lease fiber from a fiber 
provider.  Depending on your location, there might be several who can 
provide you with the glass you're looking for.  In a scenario like this, 
you're normally leasing the fiber, or possible purchasing a long-term IRU 
(Indefeasible Right to Use).

Charges are normally based on mileage and any necessary construction at 
either/both ends to get the fiber from their existing plant into your 
buildings.  Some providers will amoritize the construction costs into your 
monthly contract rate, while others will require you to pay for the 
construction separately.

Depending on the number of strands you need between points A and B and 
other considerations (multiple routes to provide physical diversity, etc), 
the provider might be willing to build a path for you, but the cost goes 
up dramatically.

Once the fiber path is completely built, make sure the provider gives you 
the results of their tests (2-point loss, OTDR graphs, etc) on the whole 
span.  The performance of the fiber and the type of optics you'll need 
to drive the link over distances of 'a few miles' will normally have much 
more to do with the quality and number of splices than the length of the 
span itself.  I've driven 1000baseLX/LH signal cleanly over fiber paths 
that were longer than 10km as long as the 2-point loss is under the link 
budget for the optics.

jms