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Glossary
SE681 WiMAX / engbt / SE681_FUG_EN_9 / Glossary.fm / 18.5.11
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Glossary
Address Translation (NAT)
N
etwork
A
ddress
T
ranslation. NAT is a method for converting IP addresses (mainly pri-
vate IP addresses) in a network to one or more public IP addresses on the Internet.
With NAT, several network components in a LAN can share a public IP address to con-
nect to the Internet. The network components of the local network are hidden behind
the IP address registered on the Internet. NAT is often used as part of the firewall in a
network because of this security function.
Bridge
A bridge connects several network segments to form a joint network, e.g. to make a
network. The segments can have different physical characteristics, e.g. differ-
ent linking such as Ethernet and wireless LANs. Local networks can be expanded by
linking individual segments via bridges.
dB
D
eci
b
el (a tenth of a Bel). Logarithmic unit of measurement for ratios between two cur-
rents, voltages, sound levels or powers. In order to depict large value differences
clearly and graphically, these are given in dB; e.g. 60 dB corresponds to the factor 1000
relative to the voltage drops.
dBm
D
eci
b
el
m
illiwatt. Power level in decibels relative to 1 milliwatt.
DHCP
D
ynamic
H
ost
C
onfiguration
P
rotocol. DHCP handles the automatic assignment of IP
addresses to network components.
DHCP was developed because in large networks – especially the Internet – the defin-
ing of IP addresses is very complex as subscribers frequently move, drop out or new
ones join. A
automatically assigns the connected network components
(DHCP clients) dynamic IP addresses from a defined IP pool range, thus saving a great
deal of configuration work. In addition, the address blocks can be used more effectively:
since not all subscribers are on the network at the same time, the same
be assigned to different network components in succession as and when required.
DHCP server
There is a DHCP integrated into the SE681 WiMAX that automatically assigns IP
addresses to PCs in the local network.
