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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: DSL line stealing when there is no tone - DANGER - Operational content
At 04:46 PM 5/16/01, Greg Maxwell wrote: Better: a chip with a recorded voice: "This pair is in use" interspersed with a tone.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. While present baseband signalling may be unable to handle such, it'd be useful if future ones purposely avoided the zero to 5kHz spectrum to allow for such a mechanism. Clearly the telco workers have demonstrated the absolute necessity for such a facility. ----------------------------------------------------------------- Daniel Senie [email protected] Amaranth Networks Inc. http://www.amaranth.com
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