FCCs RFC for the Definition of Broadband

Jack Bates jbates at brightok.net
Thu Aug 27 09:57:56 CDT 2009


Leo Bicknell wrote:
> So while mileage per subscriber increases, cost per mile dramatically
> increases.  The only advantage in an urban enviornment is that one
> trench may serve 200 families in a building, where as a rural trench
> may serve 20 familes.

Cost per subscriber is the only cost that matters. That is what defines 
your recoup time and profit margins. BTW, in many cases it's actually 
cheaper to bore the entire way then intermix boring and trenching. And 
out here, they are heavily against you trenching right through someone's 
driveway or a road. Then there's the rivers and creeks.

> But more puzzling to me is the idea that fiber becomes uneconomic.
> This may have once been true, but right now you can buy 10km or
> even 40km lasers quite cheaply.  Compare with copper which for even
> modest speeds requires a repeater every 2-4km.

Maintenance. The reason rural companies prefer active equipment in the 
plant is because of maintenance. 20 splices to restore service to 20 
customers vs 1 splice to restore service to 20 customers. This is 
oversimplified, in reality, many of the FTTH comments in this thread 
imply bringing all customers back to the CO to keep active equipment out 
of the plant. This will tend to imply large fiber bundles leaving the CO 
and breaking down smaller and smaller as you get further from the CO. A 
large fiber cut may mean 128+ splices to restore service at 1 splice per 
customer.

In addition, it throws away all the money and investment of plant 
already in the ground from key points to the customers. I haven't seen 
an installation running repeaters for copper. More common is a remote 
system fed by a fiber ring (so when the 20km fiber is cut, service isn't 
lost while repairs are done) and the last 1.5 miles fed by copper which 
is already there.

> with GigE speeds today with no intermediate equipment; the cost of
> a 20km GBIC is far less than the cost of installing 4 repeaters.
> 

If someone is setting up like this, I'd agree. More common:

Traditional POTS was often served off double ended carrier and load 
coils, which later became fiber fed integrated carrier with gr303 and 
load coils. Cheapest solution, replace carrier with DSL capable carrier, 
remove load coils when not necessary and extend from there for closer 
carriers where applicable (shorten copper loops, and removal of more 
load coils).

Here locally, we dropped over 90% of our load peds. Only the furthest 
reaches still have them and of course cannot get DSL.

> There's plenty of infrastructure built every day with ROI's of 20 years.

Hope they have disaster insurance. A good tornado or wildfire (or 
backhoe) can do some serious damage. I had both this year in Lone Grove. 
Fun. Fun. Fiber rings to remote field equipment still gives the best 
redundancy and maintenance cost (as there is less to splice over the 
longhaul to the remote system).

> service is $5 per month.  It's a 33 year ROI.  That's ok with me, it's
> infrastructure, like a road, or a bridge.  We're still using copper in
> the ground put in during the 60's, 70's, and 80's.

You bet. We're also using fiber and copper put in the ground yesterday. 
Copper is amazingly resilient. Most of the copper that has to be 
replaced is old aircore in the ground (which is why aircore shouldn't be 
in the ground, as it collects water and leads to shorts over long 
distances) or rehab of aircore in aerial due to bad boots that weren't 
maintained. The switch to fiber fed remote systems abandoned most of the 
problematic copper, though.


Jack




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