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Glossary
Gigaset DE900 IP PRO / en / A31008-M2210-R101-3x-7619 / glossary.fm / 22.03.2011
Version 2, 27.05.2010
G.729A/B
Standard for a codec.
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 networks, e.g., a router as an Internet gateway.
For phone calls from VoIP to the telephone network, a gateway has to be connected
to the IP network and the telephone network (gateway/VoIP provider). It forwards calls
from VoIP to the telephone network as required.
Gateway provider
See SIP provider.
Global IP address
See IP address.
GSM
Global System for Mobile Communication
Originally, a European standard for mobile networks. GSM can now be described as a
worldwide standard. However, in the USA and Japan, national standards were previ-
ously more frequently supported.
H
Headset
Combination of microphone and headphone. A headset makes using speaker mode
more convenient. Headsets that can be connected to the telephone via a cable are
available.
HTTP proxy
Server via which network subscribers can process their Internet traffic.
Hub
Connects several network subscribers in one infrastructure network. All data sent to
the hub by one network subscriber is forwarded to all network subscribers.
See also: Gateway, Router.
I
IEEE
Institute of Electrical and Electronics Engineers
International body that defines standards in electronics and electrical engineering,
concerned in particular with the standardisation of LAN technology, transmission pro-
tocols, data transfer rate and wiring.
Infrastructure network
Network with central structure: All network subscribers communicate via a central
router.
Instant messaging
Service that uses a client program to allow chatting in real time, i.e., to send brief mes-
sages to other subscribers on the Internet.
