USB 3.0/3.1/3.2 Gen 1 aka the kind that can do 5 gbps can only use cables up to 3m in length. Meanwhile Ethernet uses a similar twisted pair copper cable, but can do 10 gbps over 100m.
What gives, why is USB so limited in terms of cable length?
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electrically usb is voltage coupled. think of voltage as pressure, and the cable (at this length) is like a very long sponge. if you tap the pressure on one end of the tube will you detect to at the other end? yes or no? usb uses this method.
another problem is electrical noise over distance. think of that long tube getting bumped or vibrated causing pressure changes these add up over a long distance sort of like a giant antenna
in contrast ethernet is magnetically coupled. you force more electricity into and out of the cable via current flow that alternates direction. the result is current flow on the other end of the cable causes a magnetic change in the coil at the other end of the cable. this is easier to detect. this type of transmission is immune to those pressure bumps but current flow is very different and requires very strong magnets to cause noise signals.
electo magnets are like the coil of wire around a nail you did in middle school science class
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