3Com 1.024.1644-00 Modem User Manual


 
Glossary
48 56K Voice Faxmodem Internal - User’s Guide
online fallback/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.
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.