F1 and F2 lines - Explanation of Terminology

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I find I made a note when a line technician installed a replacement
drop at my house. If I understood what he told me then, I've now
forgotten. The note says:

Our F1 line appears to be 'way too long.'
Our F2 line appears very clean.

I gather from a few more clues that F1 and F2 designate the lines from
the CO to the major neighborhood connection box and from the
connection box to individual subscriber NID's.

Can someone please set me straight which is which?



Re: F1 and F2 lines - Explanation of Terminology

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Count starting from the C.O. and work outwards.

Re: F1 and F2 lines - Explanation of Terminology

baumgrenze wrote:
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They refer to "F"acility 1 and "F"acility 2. Starting closest to the
central office each cable has a start and end point. That makes up a
cable facility.

Much copper telephone plant is designed with multiple cable facilities.
The F1 facility will run from the Central Office to a cross connection
box in the neighborhood. From the cross box there will be cable
facilities that feed the neighborhood. These are the F2 facilities. If
there was yet another cross connection box, it would then be an F3
facility. You don't normally see too many of these.

Typically there will be more F2 pairs coming out of the box than F1
pairs feeding it. This is because there are spare pairs in the F2
facility for trouble purposes and also to accommodate second and third

It used to be 2 to 1, bit that ratio can change depending on the
residential/business makeup of the neighborhood.

Hope this helps.

John Dearing
A+, Network+, Server+
To Reply, just drop "yourpants" from my address! 8-)

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