3Com U.S. Robotics 56K Voice, Command Reference Manual

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G
LOSSARY
7
HDLC See High Level Data Link Control.
High Speed
Technology (HST)
3Com' proprietary signaling scheme, design and error control protocol
for high-speed modems. HST incorporates trellis-coded modulation, for
greater immunity from variable phone line conditions, and asymmetrical
modulation for more efficient use of the phone channel at speeds of
4800 bps and above. HST also incorporates MNP-compatible error
control procedures adapted to asymmetrical modulation.
Hz (Hertz) A frequency measurement unit used internationally to indicate one
cycle per second.
Industry Standard
Architecture (ISA)
The most common type of computer expansion bus. Other types
include Extended Industry Standard Architecture (EISA) and
Microchannel Architecture (MCA).
interrupt request
(IRQ)
A number that must be assigned to devices that plug in to your
computer's expansion bus.
IP Internet Protocol.
IPX Novell's Internet Packet Exchange protocol.
IRQ See interrupt request.
ISA See Industry Standard Architecture.
ITU-T International Telecommunication Union-Telecommunication sector.
Formerly referred to as CCITT. 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 .
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.