How does DSL work?

How does DLS work over an existing phone line? I was wondering how this is
technically done. Why
doesn't DSL mess with incoming phone calls? I figured some techies out there
would know the answer.

In news:(E-Mail Removed) "snow" <(E-Mail Removed)>
wrote:

> How does DLS work over an existing phone line? I was wondering how this
> is technically done. Why doesn't DSL mess with incoming phone calls? I
> figured some techies out there would know the answer.

You'll probably get a better answer over in "comp.dcom.xdsl", but an
explanation that was good enough to satisfy me is simply that the DSL
signal occupies a portion of the audio spectrum above that which carries
the voice signal of ordinary phone calls.

DSL service ->will mess up your voice service unless you install filters
to remove the DSL signal from the lines that have telephones connected to
them. Without the filter, you'll hear an annoying hiss on each of your
telephones.

In some installations, a single filter is installed where the phone line
enters your house, and all the lines to the telephone jacks run from
there, and a single unfiltered line is run to the jack where the DSL
connection will be. In other installations, individual filters are plugged
in series with the line going from the wall jack to each telephone.

--
Bert Hyman St. Paul, MN (E-Mail Removed)

In article <(E-Mail Removed)>,
snow <(E-Mail Removed)> wrote:
:How does DLS work over an existing phone line? I was wondering how this is
:technically done. Why
:doesn't DSL mess with incoming phone calls? I figured some techies out there
:would know the answer.

Regular phone calls only use about 4 KHz of bandwidth. DSL uses a much
wider range. In some implimentations of DSL, the entire range will
be used until the phone goes into use, at which point the data portion
is restricted to higher frequency ranges until the call ends [so the DSL
slows down slightly when phone calls are being made.] Other DSL
implimentations just never use that lower 4 KHz.

The copper wire that is used to carry phone conversations can handle
a lot more than 4 KHz -- it's just that 4 KHz is all of it that is
used for regular voice conversations.
--
Positrons can be described as electrons traveling backwards in time.
Certainly many Usenet arguments about the past become clearer when they
are re-interpreted as uncertainty about the future.
-- Walter Roberson

On Sun, 22 Aug 2004 19:25:14 -0400, "snow" <(E-Mail Removed)>
wrote:

>How does DLS work..?

What's a DLS? I think you mean DSL.
http://computer.howstuffworks.com/dsl.htm (12 pages)

The theory is simple. Acronyms flow down the phone line from the
phone company toward your computah. Monthly contributions of currency
flows in the other direction. When you fail to respond to the ISP's
request for money, the acronyms stop flowing. The more currency you
upload, the faster the acronyms arrive.


--
Jeff Liebermann (E-Mail Removed)
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558

"Jeff Liebermann" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> On Sun, 22 Aug 2004 19:25:14 -0400, "snow" <(E-Mail Removed)>
> wrote:
>
> >How does [DSL] work..? [snip]
>
> The theory is simple. Acronyms flow down the phone line from the
> phone company toward your computah. Monthly contributions of currency
> flows in the other direction. When you fail to respond to the ISP's
> request for money, the acronyms stop flowing. The more currency you
> upload, the faster the acronyms arrive.

Think of DSL as a dog whistle: it's on a note that humans can't hear, but
your modem can. This why people are often heard to remark that "My DSL
service is a real dog" or similar remarks.

William, who is wagging his tail like Dogbert.

On Mon, 23 Aug 2004 14:46:43 GMT, "William Warren"
<(E-Mail Removed)> wrote:

>"Jeff Liebermann" <(E-Mail Removed)> wrote in message
>news:(E-Mail Removed).. .
>> On Sun, 22 Aug 2004 19:25:14 -0400, "snow" <(E-Mail Removed)>
>> wrote:
>>
>> >How does [DSL] work..? [snip]
>>
>> The theory is simple. Acronyms flow down the phone line from the
>> phone company toward your computah. Monthly contributions of currency
>> flows in the other direction. When you fail to respond to the ISP's
>> request for money, the acronyms stop flowing. The more currency you
>> upload, the faster the acronyms arrive.

>Think of DSL as a dog whistle: it's on a note that humans can't hear, but
>your modem can. This why people are often heard to remark that "My DSL
>service is a real dog" or similar remarks.
>
>William, who is wagging his tail like Dogbert.

Woof, bow-wow, grrrrr....

Some un-named person once sent me email suggesting that anything more
than a single sentence is too long and complicated. So, here's DSL in
one sentence.

DSL seperates the low POTS frequencies, from the higher DSL data
frequencies, which are run through an adaptive equalizer, echo
canceler, and directional isolators, upon which an ATM permanent
virtual circuit is established between the ADSL modem/bridge and the
telco DSLAM, which is then fed to the ISP via a different ATM
permanent virtual circuit, terminating in the ISP's Redback ATM
router, where both the router and the ADSL modem/bridge extract the
ecapsulated TCP/IP packets, and therefore deliver IP packets between
the ISP and the customer.

See? Isn't that simpler?


--
Jeff Liebermann (E-Mail Removed)
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558

>> DSL seperates the low POTS frequencies, from the higher DSL data
frequencies, which are run through an adaptive equalizer, echo
canceler, and directional isolators, upon which an ATM permanent
virtual circuit is established between the ADSL modem/bridge and the
telco DSLAM, which is then fed to the ISP via a different ATM
permanent virtual circuit, terminating in the ISP's Redback ATM
router, where both the router and the ADSL modem/bridge extract the
ecapsulated TCP/IP packets, and therefore deliver IP packets between
the ISP and the customer.

Jeff:

What about static address/bridged (not PPPoE, no Redbacks) and PPPoA?

TIA