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Re: dry pair
From: Joel Jaeggli <joelja () darkwing uoregon edu>
Date: Fri, 29 Aug 2003 15:03:48 -0700 (PDT)


On Fri, 29 Aug 2003, Patrick Felt wrote:


I have been following the thread very intensly since I read the article that
William Warren posted.

I also have two locations that I wish to connect, and we were looking at
802.11b with cantennas.  This may not work because it looks like there are a
lot of trees between the two locations, and they may be just out of range.
We weren't sure what our other options where till this came along (we really
can't afford t1 connections).

Qwest has stated that one of the two locations has the fiber connectivity
Randy Neals mentioned below.  That does put a damper on the homebrew dsl
connectivity.

How would an alarm company get around this? 

Probably the alarm company would use slightly different gear and settle 
for what in qwest terminology is a plt (private line transport) ds0, or 
maybe dds, which is a syncronous serial service)

Would Qwest need to run copper
into the neighborhood if any one of the people purchased an alarm?

not likely. if it's a feasable buildout they'll be happy to charge you for 
the construction involved in delivering the service. but that will push 
out the delivery date and probably increase the cost to the point where 
it's not really affordable... most adt style home alarms systems use your 
existing pots telephone line anyway. most alarms circuit applications are 
to insure that things like the door on your bank vault or the cryogenic 
refrigerator in your sperm bank don't fail without someone noticing.

If not,
how would the alarm company get the signal pushed through the fiber, and
could that be done with the dsl signal?

The alarm companies need to deliver extremely small amounts of data which 
can range from make or break circuits to 60 300 or 2400bps data for things 
like building control systems, that's a considerably different problem 
than try to ram 1-7mb/s through a 25,000 foot long piece of wire.

pat
----- Original Message -----
From: "Randy Neals (ORION)" <randy.neals () orion on ca>
To: <Dan.Thorson () seagate com>
Cc: "'Austad, Jay'" <JAustad () temgweb com>; <nanog () merit edu>
Sent: Friday, August 29, 2003 2:46 PM
Subject: RE: dry pair




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
circuit.

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.  ;-)

-Randy








-- 
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Joel Jaeggli           Unix Consulting         joelja () darkwing uoregon edu    
GPG Key Fingerprint:     5C6E 0104 BAF0 40B0 5BD3 C38B F000 35AB B67F 56B2



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