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Bandwidth (was QList Netiquette?)
From: Trisha Bethen <firstname.lastname@example.org>
>Hey, guys, what do you all mean by bandwidth? <snip>
Bandwidth is the range of frequencies used to transmit a signal. In
radio terms, the bandwidth of an audio signal is from 3kHz (telephony)
to 20kHz or more (hifi or CD quality). To broadcast a 15kHz bandwidth
audio signal might require 30kHz (AM) or 200kHz (FM). Video signals
require a bandwidth of about 5 or 6 MHz.
The same term (bandwidth) is often used to describe the bits/second
required to transmit digital signals. If you send a message of 200
words to me (200words is approximately = 1Kbyte = 8Kbits), and the
message takes 10seconds to transmit, then you are using 800bits/second
Between your e-mail provider and mine there might only be a 64kbits/s
link. If other people are downloading bitmaps using this link, then
they may well use almost all the available bandwidth which means your
message might only receive 100bits/s. Now the message will take
80seconds to transmit (it still might not reach me for hours, but that
is because of the tortuous routes these messages take).
As more and more people join e-mail and the internet, less and less
bandwidth is available for each (unless governments install suitable
Here endeth the lesson - sorry about the lengthy answer.