Glossary
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online fall back/fall forward
A feature that allows a high-speed, error-control
modem to monitor line quality and fall back to the
next lower speed in a defined range if line quality
diminishes. As line conditions improve, the
modem switches up to the next higher speed.
originate mode
The mode used by your modem when initiating an
outgoing call to a destination modem. The
transmit/ receive frequencies are the reverse of the
called modem, which is in answer mode.
parity
A simple error-detection method that checks the
validity of a transmitted character. Character
checking has been surpassed by more reliable and
efficient forms of error checking, including V.42
and MNP 2-4 protocols. Either the same type of
parity must be used by two communicating
computers, or both may omit parity.
protocol
A system of rules and procedures governing
communications between two or more devices.
Protocols vary, but communicating devices must
follow the same protocol in order to exchange data.
The format of the data, readiness to receive or
send, error detection and error correction are some
of
the operations that may be defined in protocols.
RAM
Random Access Memory is memory that is
available for use when the modem is turned on, but
that clears of all information when the power is
turned off. The modem's RAM holds the current
operational settings, a flow control buffer, and a
command buffer.
remote digital loopback
A test that checks the phone link and a remote
modem's transmitter and receiver.
