| Modem | ||
| A modem converts a digital
signal (as used by computers) into an analogue
signal (as used by the telephone
system).
Digital data has distinct values but analogue data can have any value in a continuous range. (Shoe sizes are digital, temperatures are analogue)
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This process is called modulating a signal... | |
| This will allow a computer to send data down the telephone
lines to another computer. Another modem
will need to translate the analogue signal back into a digital signal so
that the receiving computer can use the data.
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..and this process is
called demodulating...
a MODEM stands for MOdulate-DEModulate. |
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| There is no need for modems if the link between computers
is digital...such as...
ISDN lines allow much faster connection between computers...but is more expensive.
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ISDN = Integrated Services Digital Network | |
| Broadband allows
greater bandwidth - this means more data
can be sent at the same time giving faster communication.
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..think of a water pipe with a larger diameter... | |
| Exercise : Modem | ||
| A modem converts a computer's
signals
into
signals so that the data can be sent over the phone lines to another computer
where a modem changes the signals back to digital.
ISDN lines are and allow much faster connection between computers. networks allow more data to be transmitted at one time.
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