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 des

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 https://en.wikipedia.org/wiki/Tape_relay IP routers now do this faster.