GLOSSARY
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online fall back/fall forward
A feature that allows high-speed, error-control modems 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 modems switch 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. 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.
remote echo
A copy of the data received by the remote system,
returned to the sending system, and displayed on the
screen. Remote echoing is a function of the remote system.