View Full Version : Re: Theory Question: ADSL loop extender

August 25th 03, 02:00 AM
"Some One" > wrote in message
> "Gene de Vore" > wrote in
> :
> > I work for a small Telephone company and we have some loop lengths
> > longer 16K foot. We are using Cisco 6160 DSLAMs setup fro G.Light.
> > Does anyone know of a way to extend the length without decreasing the
> > speed too much? we offer 640/256 and 1.5/512 currently.
> >
> > My dream goal is to extend the loop length in the few areas I have and
> > use the same CPE equipment to keep supporting of the system easier.
> >
> > TIA
> > ~Gene
> >
> >
> >
> I'm a central office tech for a big phone company and I don't know all the
> details or what your budget might be. I work in a suburban area so loop
> lengths aren't as much of a problem as they are in rural areas.
> Our ADSL circuits leave the central office either on copper pairs or on
> Litespan 2000 pairs. With the Litespans the customer is wired to a remote
> terminal, multiplexed onto an OC3 and sent to the central office terminal
> where they are demuxed. In our case the only wiring in the central office
> is for dial tone. The DSL signal somehow gets to the remote seperately.
> At the remote the DSL and dial tone are combined and sent to the customer
> on one copper pair. In this system the only loop length that matters is
> between the customer and the remote Litespan. I have relatives that are
> over 30k feet from the c.o. and get excellent DSL speeds, in the 1.3 to
> megabit range. The distance to the Litespan remote for my relatives is
> around 600 feet.

I didn't think you could get that far out with those speeds, unless they
have a Litespan RT out there (remote) since it is a DLC? Never heard of
30Kft for ADSL as I thought that was only possible for IDSL. But if that's
so, that's really great! Gene, I would say that you could also try drpping
the SNR margin on your downstream to 3dB to get better length, but then
you'd be more suseptible to link drops. Although I heard that some
providers do do that and have not had problems.