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ENGLISH
Chapter 14 - Advanced wireless network
information
What are wireless network connections?
Your wireless network adapter uses a wireless protocol (called IEEE 802.11b/g or WiFi) to
communicate with the SL400i by means of radio transmissions. WiFi radio waves travel
outwards from the antenna in all directions, and can transmit through walls and floors. WiFi can
theoretically reach up to 200 meters in an open environment and reach speeds of up to 11 (b)
or 54 (g) megabits per second (Mbps) at close range. However, the actual network range and
data throughput rate will always be less, depending on the wireless signal quality.
Factors determining your network range and network speed
•
Wireless signals travel farther outside of buildings, and when the wireless components are
in direct line of sight to one another. Putting wireless components high up helps avoid
physical obstacles and provides better coverage.
•
Building construction such as metal framing and concrete or masonry walls and floors will
reduce radio signal strength. Avoid putting wireless components next to walls and other
large, solid objects; or next to large metal objects such as computers, monitors, and
appliances.
•
Wireless signal range, speed, and strength can be affected by interference from
neighbouring wireless networks and devices. Electromagnetic devices such as televisions,
radios, microwave ovens, and cordless telephones, especially those with frequencies in the
2.4 GHz range, may also interfere with wireless transmission.
•
Standing or sitting too close to wireless equipment can also affect radio signal quality.
•
Adjusting the antennas: Certain areas, such as directly below the antenna, get relatively
poor reception. Moving the antenna slightly may improve your reception.
Note: Pointing the antenna toward another wireless component will not improve reception.
Securing your wireless network
Since wireless computer networks use radio signals, it is possible for other wireless network
devices outside your immediate area to pick up the wireless signals and either connect to your
network or to capture the network traffic.Therefore, you should always enable the Wired
Equivalent Privacy (WEP) network encryption key to help prevent unauthorised connections or
the possibility of eavesdroppers listening in on your network traffic.
What is WEP?
WEP is a 64-bit or 128 bit encryption key for securing your wireless network communication.
Preferably, you should use the highest encryption strength available. Always enter the same key
with the same length for all your home network computers and for the SL400i.
Securing your network from Internet access
Check in the documentation of your Wireless Base Station or gateway router whether it
provides you with a built-in firewall and network address translation (NAT), providing security
for an ‘always-on’ broadband Internet connection that is being shared among the computers
and devices on your home network.
Computers on an ad-hoc network may share an Internet connection that is set up on one of
the computers (ICS). However, a firewall is usually not built-in and you should install one on the
computer that is sharing the Internet connection.
What is a firewall?
A firewall acts as a barrier that helps protect your network from outside intruders.The firewall
specifies what information can be communicated from the computers on your network to the
Internet, and from the Internet to the computers on your network.
