![background image](http://html1.mh-extra.com/html/3com/005687-03/005687-03_manual_440884120.webp)
G
LOSSARY
116
full duplex
Signals can flow in both directions at the same
time over one line. In microcomputer
communications, may refer to the suppression
of the online
local echo
.
half duplex
Signals can 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, a frequency measurement unit used
internationally to indicate cycles per second.
ITU-T
An international organization that defines
standards for telegraphic and telephone
equipment. For example, the Bell 212A
standard for 1200-bps communication in
North America is observed internationally as
ITU-T
V.22
. For 2400-bps communication,
most U.S. manufacturers observe V.22 bis.
LAPM
Link Access Procedure for Modems. An
error-control
protocol
defined in
ITU-T
Recommendation V.42. Like the
MNP
protocols, LAPM uses
cyclic redundancy
checking
(
CRC
) and retransmission of
corrupted data (
ARQ
) to ensure data
reliability.