DSL line stealing when there is no tone - DANGER - Operational content

John Fraizer nanog at Overkill.EnterZone.Net
Thu May 17 18:02:29 UTC 2001

On Wed, 16 May 2001, Greg Maxwell wrote:

> On Wed, 16 May 2001, Steve Schaefer wrote:
> > The main reason not to stick a tone on the DSL line is that the line
> > coding (2B1Q) used by SDSL uses the baseband (low frequency part of the
> > spectrum).
> > 
> > For line codings that don't use the baseband (CAP, DMT and variants like
> > G.lite), the DSLAM (telco central office DSL equipment) is always set up
> > so that the DSL can be combined with a voice circuit over the same pair,
> > so it still doesn't put a tone on the line.
> I predict great profits for the first person to duct tape 100 'tracer
> tone-generators' into a 23 inch rack with 48v DC power source. 
> --
> The comments and opinions expressed herein are those of the author of this 
> message and may not reflect the policies of the Martin County Board of
> County Commissioners.

I predict great great headache for the same person.  Typically, the
line-tech is looking for those tones and this will make your lines even
more likely to be fudged with.

John Fraizer
EnterZone, Inc

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