Re:Why 56k is the fastest dial up modem speed
by Merrill on Saturday November 25, 2023 @12:30PM
(#38414921)
At one time teletype switching was done in centers where the incoming line was connected to a tape punch. The operator tore the tape off the punch, read the destination address punched at the beginning of the tape, and put the tape on a tape reader connected to an outgoing line to another center closer to the destination. https://en.wikipedia.org/wiki/Tape_relay
IP routers now do this faster.