Why there is a bandwidth limitations in serial ports

hi all
why there is a bandwidth limitations in serial ports ??
like the highest one is 45 mbps
but Ethernet ports reach 100 GB !!
thanks,

Dear,
each standard has its own specification about media, connectors and protocols. Depending on the type of media and technologies that ware available when the standard has been defined, a maximum speed has also been defined. The speed depends on the specific media (copper or optical, twisted pair or coax, cat 5 or cat 6), electrical signals (volts, waveform, clock), distance between device,.... each protocol defines a maximum speed. It's true that ethernet protocols have a very high speed but over a copper line they are also limited to 100 meters while other serial protocols, xDSL for example, can transmit up to 20Mbps over copper line over a distance of some kilometre. So speed reduction is often a way to have longer connections.
Bye,
enrico
PS: please rate if useful

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Why there is a bandwidth limitations in serial ports

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