at the risk of being pedantic DSL is a digital *service*. it still uses high frequency carrier wave modulation (analog signal transmission) to transmit the data. hence the use of modulation/demodulation technology. ADSL happens to modulate frequencies on the line which are outside the normal phone spectrum and it's this spectral separation that allows co-residence with standard analog voice services. other flavors do/don't allow for this but operate on largely the same principles. signal processing is a wonderful thing. On Thu, Jan 16, 2014 at 7:55 AM, Carl Wilhelm Soderstrom <chrome at real-time.com> wrote: > On 01/15 07:33 , Jay Kline wrote: >> I thought anything that modulated an analog signal to a digital signal (and >> the reverse) was a modem. It may not be audible, but it is an analog signal. > > But in the case of a DSL or cable Internet connection, it is digital on the > wire. (Arguably I suppose in the case of a POTS telephone connection it uses > discrete tones, so could be called 'digital' since it doesn't use a smooth > wave). > > -- > Carl Soderstrom > Systems Administrator > Real-Time Enterprises > www.real-time.com > _______________________________________________ > TCLUG Mailing List - Minneapolis/St. Paul, Minnesota > tclug-list at mn-linux.org > http://mailman.mn-linux.org/mailman/listinfo/tclug-list -- steve ulrich (sulrich at botwerks.*)