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RE: dry pair
From: "Randy Neals (ORION)" <randy.neals () orion on ca>
Date: Fri, 29 Aug 2003 16:46:13 -0400

From: Dan.Thorson () seagate com
From what I recall there is no guarentee that the Qwest 
tarrif for NB3 is actually a straight-through copper pair
[section 7.3.1.B.2.a.(4)]... note the restriction of
signaling frequency.... 
see the Terms & Conditions in section 7.3.1.B.2.a.(2).

By requesting a circuit that offers 60Hz and/or DC signalling that
pretty much requires them to use Copper, if they have it available. The
only way to know if they have it available is to order the circuit.
After a few days the order will hit their design department which will
look at the order and determine if facilities exist to provison the

Some newer office towers and subdivisons/developments may be fed with
fiber using Digital Loop Carrier(DLC/SLC) equipment in a CEV hut. While
there is still a copper loop to each home or business from the CEV/Hut,
the loop ends at the SLC and the voice is converted to PCM over fiber to
extend to the C.O.

Our Telco uses a slightly different wording in their Tariff for this
lack of DC continuity disclaimer...:
"The provisioning of metallic or DC continuity applied until 1993 12 31.
Thereafter, the provisioning of metallic or DC continuity is provided
only where metallic facilities currently exist, following normal
provisioning practices.
Where capacity is exhausted, or where appropriate facilities do not
exist, the Company will evaluate all requests and only provide
end-to-end metallic facilities at the customer's expense based on the
cost incurred by the Company."

The largest concern is usually the length of the circuit because how
they route the circuit is not always intuitive and the cable may take a
circuitous route between your two locations. Usually they can estimate
the loop length when the do the design.

The limitation on frequency/pulses is largely administrative verbiage. I
highly doubt they will install a filter on the circuit to prevent higher
speed. (Although it is possible)
At one time I think the different speed circuits where priced
differently. I suppose a few decades ago the differnce between 30 bits
per second and 75 bits per second was considered a large amount of
difference.  ;-)


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