Unformatted text preview: nnection for communication, they try to establish which protocols
they share, and then they use the fastest rate that both modems have. That is, if
two computers, one with 9600 bps modem and the other one with 14400 bps
modem, try to communicate, the data would be transferred between the two
computers at 9600 bps. Hence, a fast modem just provides you the option to
communicate faster when you can.
2. Internal versus external. Modems are of two kinds, internal and external. An
internal modem is an optional add-on circuit board that plugs into one of the
computer's expansion slots. It gets its power from the computer's expansion bus. It
is manufactured and supplied by the computer manufacturer itself.
An external modem, on the other hand, is a separate box that contains the circuitry
and logic to modulate data signals. It has its own power supply, on/off switch, and
front-panel LCDs to indicate its status. For this reason, external modems are
slightly more expensive. An external modem is connected to the computer via a
Both the internal as well as external modems connect to the telephone system with
a standard telephone jack. However, each one has its own advantages and
disadvantages. Internal modems are slightly faster and do not have external wires
and power cords hanging around. However, as they plug into one of the
computer's expansion slots, this may be a problem if free slots are scarce. External
modems are slightly costlier and have external wires and power cords. They also
need one of the built-in serial ports of the computer, which may be a problem if there are few other devices that also require a serial port for connectivity.
However, external modems have the flexibility of being switched off independent
of the computer, and if there is any problem with the modem hardware/software,
the computer need not be sent for repair and maintenance (only the modem can be
3. Facsimile facility. Some modems, known as FAX modems, are capable of
emulating a FAX machine in add...
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This document was uploaded on 04/07/2014.
- Spring '14