ZyXEL Communications EMG6726-B10A, Руководство пользователя

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Chapter 7 Wireless
EMG6726/8726-B10A User’s Guide
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Figure 40 Example of a Wireless Network
The wireless network is the part in the blue circle. In this wireless network, devices A and B use the access
point ( AP ) to interact with the other devices (such as the printer) or with the Internet. Your EMG is the AP.
Every wireless network must follow these basic guidelines.
• Every device in the same wireless network must use the same SSID.
The SSID is the name of the wireless network. It stands for Service Set IDentifier.
• If two wireless networks overlap, they should use a different channel.
Like radio stations or television channels, each wireless network uses a specific channel, or frequency,
to send and receive information.
• Every device in the same wireless network must use security compatible with the AP.
Security stops unauthorized devices from using the wireless network. It can also protect the
information that is sent in the wireless network.
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.