Glossary - ZyXEL Communications Omni 56K User Manual

Analog An electrical circuit that is represented by means of continuous, variable physical quantities
(such as voltages and frequencies), as opposed to discrete representations (like the 0/1,
off/on representation of digital circuits).
Testing method in which the modem's analog signal is connected to the analog input.
Analog Loopback
Test
In a connection between two modems, one modem works as the recipient (in answer mode)
Answer
and the second modem as the initiator (originate mode).
Architecture A design. The term architecture can refer to either hardware or software, or to a
combination of hardware and software. The architecture of a system always defines its
broad outlines, and may define precise mechanisms as well.
Automatic Retransmission reQuest – standardized method in error control protocols.
ARQ
ASCII American Standard Code for Information Interchange. This code assigns a 7-bit numerical
value to characters, digits and control characters. An ASCII character is a 7-bit character
with a decimal value ranging from 0 to 127.
Asynchronous Data transfer method in which a character's data bits are framed by additional bits (start bit,
parity bit and stop bit). There are variable idle times between characters.
AT Command The commands used with an intelligent modem. Every command line is started with the
AT
communications software running.
Authenticity Proof that the information came from the person or location that reportedly sent it. One
example of authenticating software is through digital signatures.
Auto-answer Modem's ability to automatically answer a call after a set number of rings.
A high-speed line or series of connections that forms a major pathway within a network.
Backbone
Bandwidth This is the capacity on a link usually measured in bits-per-second (bps).
bis Old French word for two.
(Binary Digit) – A single digit number in base-2, in other words, either a one or a zero. The
Bit
smallest unit of computerized data.
Count of data bits transmitted per time unit. The framing bits needed for asynchronous
Bit Rate
transfer are also counted in the calculation of the bit rate. In general, the bit rate is ten times
the character rate.
bps Unit of measurement. Bits per second.
A set of bits that represent a single character. There are 8 bits in a Byte.
Byte
Carrier The carrier is a modulated tone and is used by the modem to transfer the data.
Comité Consultatif International Thonique et Traphique; former name for the ITU-TSS
CCITT
(ITU-T), the international standard making organization for telecommunications.
CD See DCD.
prefix (ATtention). To send an
User's Guide for ZyXEL Omni 56K USB Modem
AT
command to a modem, you must have

Glossary

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