3Com Courier, Справочник

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8 G
LOSSARY
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 .
jumper A switch composed of pins and a shunt. The shunt's position on the
pins determines the jumper setting.
Kbps Kilobits per second, or thousand bits per second.
LAPM See Link Access Procedure for Modems.
Link Access
Procedure for
Modems (LAPM)
Link Access Procedure for Modems, an error control protocol
incorporated in ITU-T Recommendation V.42. Like the MNP and HST
protocols, LAPM uses cyclic redundancy checking (CRC) and
retransmission of corrupted data (ARQ) to ensure data reliability.
local echo A modem feature that enables the modem to send copies of keyboard
commands and transmitted data to the screen. When the modem is i
Command mode (not online to another system) the local echo is
invoked through the ATE1 command. The command causes the modem
to display your typed commands. When the modem is online to
another system, the local echo is invoked through the ATF0 command
This command causes the modem to display the data it transmits to the
remote system.
MB
Megabyte. One million bytes.
Microcom
Networking Protocol
(MNP)
An asynchronous error control protocol developed by Microcom, Inc.
and now in the public domain. The protocol ensures error-free
transmission through error detection (CRC) and retransmission of
errored frames. 3Com modems use MNP Levels 1-4 and Level 5 data
compression. MNP Levels 1-4 have been incorporated into ITU-T
Recommendation V.42. Compare HST.
MNP See Microcom Networking Protocol.
modem A device that transmits/receives computer data through a
communications channel such as radio or telephone lines. The Courier
V.Everything modem is a telephone channel modem that modulates, or
transforms, digital signals from a computer into the analogue form that
can be carried successfully on a phone line. It also demodulates signals
received from the phone line back to digital signals before passing
them to the receiving computer