ZyXEL Communications Omni 56K User Manual page 74

User's Guide for ZyXEL Omni 56K USB Modem
lines with some combination of asynchronous transfer mode (ATM), frame relay, or IP
networks.
DSR Data Set Ready – a control signal line of the RS-232C standard.
Originally, the DTE (data terminal equipment) meant a dumb terminal or printer, but today
DTE
it is a computer, or a bridge or router that interconnects local area networks.
DTMF Dual Tone Multi-Frequency. The technology used in pushbutton telephones, commonly
known as touchtone, of generating audible notes to represent numbers.
DTR Data Terminal Ready – a control signal line of the RS-232C standard interface. Some
computers set this signal when they are turned on, even if they are not able to receive data.
Echo For a modem user, echo has two meanings: A modem can return all received characters to
its local terminal/computer so they can be seen on-screen. The other meaning of the term
"echo" is that part of the analog signal the modem sent out is bounced back by the
telephone network to the modem's receiver, mixing there with the remote modem's signal.
Extended Distinctive Ring – A feature of ZyXEL modems that helps to distinguish between
EDR
data, fax and voice calls.
An Electronically Erasable and Programmable Read Only Memory. Such a device is used
EEPROM
in ZyXEL modems to store settings and profiles. An EEPROM does not lose data when the
modem is turned off.
EIA Electronic Industry Association (of North America); this organization was the first to draft
a standard serial port (RS-232C).
ElectroMagnetic Interference. The interference by electromagnetic signals that can cause
EMI
reduced data integrity and increased error rates on transmission channels.
Encryption The act of substituting numbers and characters in a file so that the file is unreadable until it
is decrypted. Encryption is usually done using a mathematical formula that determines how
the file is decrypted.
EPROM Electrically Programmable Read Only Memory. A memory chip that 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.
Ethernet A very common method of networking computers in a LAN. There are a number of
adaptations to the IEEE 802.3 Ethernet standard, including adaptations with data rates of 10
Mbits/sec and 100 Mbits/sec over coaxial cable, twisted-pair cable, and fiber-optic cable.
The latest version of Ethernet, Gigabit Ethernet, has a data rate of 1 Gbit/sec.
Events These are network activities. Some activities are direct attacks on your system, while others
might be depending on the circumstances. Therefore, any activity, regardless of severity is
called an event. An event may or may not be a direct attack on your system.
(Frequently Asked Questions) – FAQs are documents that list and answer the most
FAQ
common questions on a particular subject.
Fax Long distance copy; facsimile – transfer of graphical data between two fax units. The
graphical data is compressed during transfer (G3).
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