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Glossary
Gigaset C450 IP / Greek eng / A31008-M1713-T151-3-8U19 / glossary.fm / 24.9.07
Ver
si
on 4, 16.
09.20
05
G
G.711 a law, G.711 µ law
.
G.711 delivers a very good voice qual-
ity that corresponds to that in the ISDN
fixed network. As there is little com-
pression, the necessary bandwidth is
approx. 64 Kbit/s per voice connection,
but the delay caused by coding/decod-
ing is only 0.125 ms.
"a law" describes the European stand-
ard and "
μ
law" describes the North
American/Japanese equivalent.
G.726
.
G.726 delivers a good voice quality. It is
inferior to the quality with codec
G.711
but better than with
G.729
.
G.729A/B
.
The voice quality is rather less with
G.729A/B. As a result of the high level
of compression, the necessary band-
width is only approx. 8 Kbit/s per voice
connection, but the delay is approx. 15
ms.
Gateway
Connects two different
with
one another, e.g. router as Internet
gateway.
For phone calls from
to the tele-
phone network, a gateway has to be
connected to the IP network and the
telephone network (gateway/VoIP pro-
vider). It forwards calls from VoIP to the
telephone network as required.
Gateway Provider
.
GSM
Global System for Mobile Communication
Originally, European standard for
mobile networks. GSM can now be
described as a worldwide standard. In
the USA and Japan national standards
are now more frequently supported
than in the past.
H
Headset
Combination of microphone and head-
phone. A headset makes handsfree
talking more comfortable. There are
headsets available which are con-
nected to the handset by a cable.
Hold music
Music on hold
Music is played while you are making
a
.
The waiting participant hears music
while on hold.
HTTP proxy
can process their Internet traffic.
Hub
Connects several
in one
. All
data sent to the hub by one network
subscriber is forwarded to all network
subscribers.
See also: