ZyXEL U-90E User Guide - Page 142

EPROM, Error, correction, High-speed modem, Internet, FIFO-Buffer, Firmware, Flash, Flow control

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U-90E Data/Fax Modem EPROM: Electrically Programmable Read Only Memory. A memory chip which may be programmed electronically, but must be exposed to ultraviolet radiation to be erased. Error correction: A method to compensate for errors which occurred in the transmission path. Error correction is done by the modems and is transparent to the DTEs. The most familiar correction methods are MNP5 and V.42bis. Fax: Long distance copy; facsimile - transfer of graphical data between two fax units. The graphical data is compressed during transfer (G3). FIFO-Buffer: First-in-first-out buffer. A buffer of this type is used in the 16550 type UARTs which allow higher data throughput rates on PCs. Firmware: The ZyXEL modems' system software is located in flash EPROMs. Depending on the size of the EPROM(s), some features may or may not be available. Flash: Memory designed for multi-purposes. Flow control: Method to stop and start the data flow to avoid loss of data. Front panel: The front panel on the ZyXEL modems consists of LED indicators and key switches. Full-duplex: Transmission link where transmission can take place in both directions simultaneously. FSK: Frequency Shift Keying - a frequency modulation scheme. G3 fax: Several fax standards exist. Most available fax machines use the group 3 (G3) standard. This standard defines the compression of graphic data and a transmission speed of up to 14400 bps with an automatic fallback to 2400 bps if the telephone line is bad. Handshake: At the beginning of a connection, the modems must negotiate and initialize the protocols to be used and the speed at which the connection is to be established. This negotiation phase and the following initialization phase is called handshake. HDLC: High-level Data Link Control - protocol for synchronous transfer. High-speed modem: A modem that works at bit rates higher than 9600 bps. Hook-Flash: The hook-flash is a signal used in a dial sequence. This signal may be used for call transfers or to request an outside line on certain PABX. Hz: Hertz. A unit of measurement for frequency. Cycles per second. Internet: The worldwide collection of networks and computers, linked together to create a global community for D Glossary

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U-90E Data/Fax Modem
EPROM
: Electrically Programmable Read Only Memory. A memory chip which may be programmed electronically, but
must be exposed to ultraviolet radiation to be erased.
Error
correction
: A method to compensate for errors which occurred in the transmission path. Error correction is done
by the modems and is transparent to the DTEs. The most familiar correction methods are MNP5 and V.42bis.
Fax
: Long distance copy; facsimile - transfer of graphical data between two fax units. The graphical data is compressed
during transfer (G3).
High-speed modem
: A modem that works at bit rates higher than 9600 bps.
Internet
: The worldwide collection of networks and computers, linked together to create a global community for
FIFO-Buffer
: First-in-first-out buffer. A buffer of this type is used in the 16550 type UARTs which allow higher data
throughput rates on PCs.
Firmware
: The ZyXEL modems' system software is located in flash EPROMs. Depending on the size of the EPROM(s),
some features may or may not be available.
Flash
: Memory designed for multi-purposes.
Flow control
: Method to stop and start the data flow to avoid loss of data.
Front panel
: The front panel on the ZyXEL modems consists of LED indicators and key switches.
Full-duplex
: Transmission link where transmission can take place in both directions simultaneously.
FSK
: Frequency Shift Keying - a frequency modulation scheme.
G3 fax
: Several fax standards exist. Most available fax machines use the group 3 (G3) standard. This standard defines the
compression of graphic data and a transmission speed of up to 14400 bps with an automatic fallback to 2400 bps if the
telephone line is bad.
Handshake
: At the beginning of a connection, the modems must negotiate and initialize the protocols to be used and the
speed at which the connection is to be established. This negotiation phase and the following initialization phase is called
handshake.
HDLC
: High-level Data Link Control - protocol for synchronous transfer.
Hook-Flash
: The hook-flash is a signal used in a dial sequence. This signal may be used for call transfers or to request an
outside line on certain PABX.
Hz
: Hertz. A unit of measurement for frequency. Cycles per second.
Glossary
D