On 2021-11-21 14:24, I wrote: >> >> (DSL is a great practical illustration of Claude Shannon's famous theorem >> IMO. Some modems can even display a bar-chart of the number of bits >> negotiated per bin over the total bandwidth.)
Out of idle curiosity I had a look at the performance of my own FTTN modem at the end of about 1Km of fairly old, rural & regional, and now rather wet, copper. Each DSL "bin" has 4.3125 KHz of bandwidth. The number of bits transmitted per bin varies from 1 to 13, and the resulting downstream bitrate per bin varies from 1.2040 to 13.640 Kbit/s. Now 1.2040 Kbit/s over a single 4.3125 KHz bin sounds to me very like an old 1,200/75 bit/s dialup modem running over a PMG copper tail about 35 years ago. But I now get around 30/6 Mbits/s from the same tail, Claude Shannon be blessed! DL _______________________________________________ Link mailing list [email protected] https://mailman.anu.edu.au/mailman/listinfo/link
