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Glossary
Gigaset A580 IP / GBR / A31008-xxxx-xxxx-x-xxxx / glossary.fm / 24.03.2010
V
e
rsion 8, 03.0
9
.2008
Full duplex
Data transmission is a mode in which data can be sent and received at the same
time.
G
G.711 a law, G.711 μ law
Standard for a
.
G.711 delivers a very good voice quality that corresponds to that in the ISDN fixed
line. As there is little compression, the necessary bandwidth is around 64 kbit/s per
voice connection, but the delay caused by coding/decoding is only 0.125 ms.
"a law" describes the European standard and "μ law" describes the North American/
Japanese equivalent.
G.722
Standard for a
.
G.722 is a
broadband
language codec with a bandwidth of 50 Hz to 7 kHz, a net
transmission rate of 64 kbit/s per voice connection and integrated speech pause
recognition and comfort noise generation (silence suppression).
G.722 delivers very good voice quality. A higher sampling rate provides clearer and
better voice quality than other codecs and enables a speech tone in High Definition
Sound Performance (HDSP).
G.726
Standard for a
.
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
Standard for a
.
The voice quality is more likely to be lower with G.729A/B. As a result of the high
level of compression, the necessary bandwidth is only around 8 kbit/s per voice
connection, but the delay is around 15 ms.
Gateway
Connects two different
, e.g. a router as an Internet gateway.
For phone calls from
to the telephone network, a gateway has to be con-
nected to the IP network and the telephone network (gateway/VoIP provider). It
forwards calls from VoIP to the telephone network as required.
Gateway provider
£
Global IP address
£
.
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 fre-
quently supported than in the past.