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 Chapter 7 Wireless LAN

P-870H/HW Series User’s Guide

87

network’s name. This helps you identify your wireless network when wireless 
networks’ coverage areas overlap and you have a variety of networks to choose 
from. 

Radio Channels

In the radio spectrum, there are certain frequency bands allocated for unlicensed, 
civilian use. For the purposes of wireless networking, these bands are divided into 
numerous channels. This allows a variety of networks to exist in the same place 
without interfering with one another. When you create a network, you must select 
a channel to use. 

Since the available unlicensed spectrum varies from one country to another, the 
number of available channels also varies. 

Wireless Security

By their nature, radio communications are simple to intercept. For wireless data 
networks, this means that anyone within range of a wireless network without 
security can not only read the data passing over the airwaves, but also join the 
network. Once an unauthorized person has access to the network s/he can either 
steal information or introduce malware (malicious software) intended to 
compromise the network. For these reasons, a variety of security systems have 
been developed to ensure that only authorized people can use a wireless data 
network, or understand the data carried on it.

These security standards do two things. First, they authenticate. This means that 
only people presenting the right credentials (often a username and password, or a 
“key” phrase) can access the network. Second, they encrypt. This means that the 
information sent over the air is encoded. Only people with the code key can 
understand the information, and only people who have been authenticated are 
given the code key.

These security standards vary in effectiveness. Some can be broken, such as the 
old Wired Equivalent Protocol (WEP). Using WEP is better than using no security at 
all, but it will not keep a determined attacker out. Other security standards are 
secure in themselves but can be broken if a user does not use them properly. For 
example, the WPA-PSK security standard is perfectly secure if you use a long key 
which is difficult for an attacker’s software to guess - for example, a twenty-letter 
long string of apparently random numbers and letters - but it is not very secure if 
you use a short key which is very easy to guess - for example, a three-letter word 
from the dictionary.

Because of the damage that can be done by a malicious attacker, it’s not just 
people who have sensitive information on their network who should use security. 
Everybody who uses any wireless network should ensure that effective security is 
in place.

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