On Jan 29, 2013, at 20:36 , George Herbert <george.herbert@gmail.com> wrote:
On Tue, Jan 29, 2013 at 8:10 PM, Leo Bicknell <bicknell@ufp.org> wrote:
In a message written on Tue, Jan 29, 2013 at 07:46:06PM -0800, Owen DeLong wrote:
Case 2, you move the CO Full problem from the CO to the adjacent cable vaults. Even with fiber, a 10,000 strand bundle is not small.
It's also a lot more expensive to pull in 10,000 strands from a few blocks away than it is to drop a router in the building with the MMR and aggregate those cross-connects into a much smaller number of fibers leaving the MMR building. [snip] But what happens when you fill the cable vaults?
It's really not an issue. 10,000 fibers will fit in a space not much larger than my arm.
I have on my desk a 10+ year old cable sample of a Corning 864 strand cable (36 ribbons of 24 fibers a ribbon). It is barely larger around than my thumb. Each one terminated into an almost-full rack of SC patch panels.
It's more than just terminating it; the bulk fiber is not free. And it's not the customer end where you see congestion; unless you (expensively) splice out in the field at intermediate aggregation points, for a say 10,000 customer "wire center" you have 10,000 x the individual cable cross section area at the convergence point. Which you have to provision end-to-end unbroken as splicing is likely to screw with your overall cost model in an atrocious way. Unlike all the other media.
This can be addressed by the fiberoptic equivalent of Telco "B Boxes" out in the neighborhoods. You run a large fiber bundle to the "B Box" (or series of B Boxes) and run the individual fiber bundles from the B Box to each house in the immediate neighborhood. Same model as the current Telco F1/F2 cable bundles, etc.
It's a pain in the ass to provision in a way that you can centralize a L1 dark fiber service, because of splices. If you're providing L2 then you don't splice, you just run to a pole or ground or vault box and terminate there, and have a few 10G or 40G or 100G uplink fibers from there to your interchange point "wire center". If you're providing L1 then that's an amazingly complex fiber pull / conduit / delivered fiber quality / space management problem at the wire center.
I don't think this is necessarily true if you include the possibility of passive LC patching at the neighborhood level. Owen