3Com 1.024.1644-00 - Manual (Page 52)

Glossary
46 56K Voice Faxmodem Internal - User’s Guide
error control
A variety of techniques that check the reliability of characters (parity) or
blocks of data. V.42 and MNP error-control protocols use error detection
(CRC) and retransmission of flawed frames (ARQ).
facsimile
A method for transmitting the image on a page from one point to another.
This is commonly referred to as fax.
fax mode
The mode in which the faxmodem is capable of sending and receiving files
in a facsimile format. See definitions for V.17, V.27ter, V.29.
flow control
A mechanism that compensates for differences in the flow of data into and
out of a modem or other device. See commands &Hn, &In, &Rn.
frame
A data communications term for a block of data with header and trailer
information attached. The added information usually includes a frame
number, block size data, error-check codes, and Start/End indicators.
full duplex
These signals will flow in both directions at the same time. In
microcomputer communications, may refer to the suppression of the on-
line local echo.
half duplex
These signals will flow in both directions, but only one way at a time. In
microcomputer communications, may refer to activation of the online
local echo, which causes the modem to send a copy of the transmitted
data to the screen of the sending computer.
Hz
Hertz is a frequency measurement unit used internationally to indicate
one cycle per second.