ZyXEL Communications ARMOR G5, Руководство пользователя, Страница: 105 / 186

Chapter 10 Wireless LAN
NBG7815 User’s Guide
105
• Use the
WPS
screen to quickly set up a wireless network with strong security without having to
configure security settings manually ( Section 10.5 on page 113 ).
• Use the
Sc he duling
screen to set the times your wireless LAN is turned on and off ( Section 10.6 on
page 115 ).
10.1.2 Wha t Yo u Sho uld Kno w
Every wireless network must follow these basic guidelines.
• Every wireless client in the same wireless network must use the same Service Set Identifier (SSID).
The SSID is the name of the wireless network.
• If two wireless networks overlap, they should use different channels.
Like radio stations or television channels, each wireless network uses a specific channel, or frequency,
to send and receive information.
• Every wireless client in the same wireless network must use security compatible with the AP.
Security stops unauthorized devices from using the wireless network. It also protects information that is
sent through the wireless network.
Wire le ss Se c urity O ve rvie w
The following sections introduce different types of wireless security you can set up in the wireless
network.
SSID
Normally, the AP acts like a beacon and regularly broadcasts the SSID in the area. You can hide the
SSID instead, in which case the AP does not broadcast the SSID. In addition, you should change the
default SSID to something that is difficult to guess.
This type of security is fairly weak, however, because there are ways for unauthorized devices to get the
SSID. In addition, unauthorized devices can still see the information that is sent in the wireless network.
MAC Addre ss Filte r
Every wireless client has a unique identification number, called a MAC address.
1
A MAC address is
usually written using twelve hexadecimal characters
2
; for example, 00A0C5000002 or 00:A0:C5:00:00:02.
To get the MAC address for each wireless client, see the appropriate User’s Guide or other
documentation.
You can use the MAC address filter to tell the AP which wireless clients are allowed or not allowed to use
the wireless network. If a wireless client is allowed to use the wireless network, it still has to have the
correct settings (SSID, channel, and security). If a wireless client is not allowed to use the wireless
network, it does not matter if it has the correct settings.
This type of security does not protect the information that is sent in the wireless network. Furthermore,
there are ways for unauthorized devices to get the MAC address of an authorized wireless client. Then,
they can use that MAC address to use the wireless network.
1. Some wireless devices, such as scanners, can detect wireless networks but cannot use wireless networks. These
kinds of wireless devices might not have MAC addresses.
2. Hexadecimal characters are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, and F.