Devolo GIGAGATE, Руководство пользователя

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Introduction 11
devolo GigaGate
The wireless network established by an access
point has only limited range. The reception
range of the access point, also known as a
"radio cell", is impeded by the walls of a
building. In some cases, stable connections are
often only possible between WiFi devices
within a single room.
Since it is not possible to rely on hardware such
as network cables (in a LAN) or household
wiring (in a dLAN) to control access to a WiFi
network, wireless networking naturally
presents special security challenges. WiFi
networks therefore use a number of security
measures, such as a concealed network name
(SSID - Service Set Identifier), data encryption
and access control via the MAC addresses of
the devices (clients).
2.1.1 Wi-Fi or WLAN?
Wi-Fi is an invented brand name of the Wi-Fi
Alliance, a consortium that certifies devices
with wireless interfaces. In many countries,
Wi-Fi is also used synonymously with WLAN,
which if taken strictly, is incorrect, because Wi-
Fi designates the wireless standard and WLAN
the wireless network.
2.1.2 Differences in WiFi
frequency bands
The devolo GigaGate supports WiFi
frequencies of 2.4 GHz and 5 GHz for an
optimal WiFi transmission rate.
Both frequency bands have their pros and cons
and showcase their strengths best when
combined together.
2.4 GHz frequency band
The 2.4 GHz frequency band is used by many
everyday wireless devices, e.g. by cordless
phones, microwaves, Bluetooth devices and
network devices that rely on the 802.11b,
802.11g and 802.11n WiFi standards. The high
level of spread is also a decisive disadvantage
because there are only a few channels free of
overlap in the 2.4 GHz frequency band that can
be used in parallel and without interference
for WiFi. In addition, the large number of