IP Dual Port PBXgateway and Remote System Administrator’s Guide
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such as a letter, numeral, or punctuation mark.
CODECS
Codec refers to "Coder-Decoder," which describes a device or
program capable of performing transformations on a data stream or
signal.
Companding
A type of signal processing in which the signal is compressed on
input and expanded back to its original form on output. Digital
companding allows a device to achieve a greater apparent dynamic
range with fewer bits per sample word.
Compression
A technology that reduces the size of a file. Compression programs
are valuable to network adminstrators because they help save both
time and bandwidth.
Console
An interactive terminal connected to a computer or electronic
system usually for the purposes of administration.
D
Daemon
A program that runs unattended to perform continuous or periodic
systemwide functions, such as network monitoring or control.
dB
A unit used to convey the intensity of sound.
DB9
On a PC, the serial port is a DB9 male connector. It has 9 pins
arranged in two rows, with one row on top of the other.
DHCP
Short for Dynamic Host Configuration Protocol, a protocol for
assigning dynamic IP addresses to devices on a network. With
dynamic addressing, a device can have a different IP address every
time it connects to the network. DHCP also supports a mix of static
and dynamic IP addresses.
Dial Tone
This sound signifies that a telephone is ready to receive instruction
(i.e. make a call).
DiffServ
Is an architecture for providing different types or levels of service for
network traffic. One key characteristic of diffserv is that flows are
aggregated in the network, so that core routers only need to
distinguish a comparably small number of aggregated flows, even if
those flows contain thousands or millions of individual flows
Digital Phones
A telephone that uses signaling rather than pulses (as in an analog
phone). Most PBXs/KTSs use digital phones as the user interface.
Domain Name
A domain name is the text name corresponding to the numeric IP
address of a computer on the Internet.
DTMF
Dual Tone Multi-Frequency; better known as a Touch Tone. The
tones generated by touching the keys on the phone are used for a
variety of purposes including voice mail systems and voice
messaging.
Duty Cycle
In an ideal pulse train (one having rectangular pulses) it’s the ratio
of the pulse duration to the pulse period.
E
Echo
An interference present on telephone circuits in which transmitted
signals are reflected back to the source from the terminating end.
This is usually overcome by the telephone company by the
installation of echo suppressors in the transmission path which
absorb the echo when each party is talking.
EXTender
A communications solution offered by Citel Technologies that allows
for seamlessly connecting remote offices to the corporate PBX or
KTS. The EXTender resides at the remote site.
Extensions
A telephone extension is an internal telephone line attached to a
Document Number: M-4100-MUC
Version: Rev AA
© Copyright 2007 Citel plc All Rights Reserved
