ZyXEL Communications NBG318S Series, Руководство пользователя

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Chapter 5 Wireless LAN
NBG318S User’s Guide
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( ) WPA2 (TKIP or AES)
• Preamble type (if available): auto, short or long
To set up your wireless network without an AP or wireless router, make sure wireless network
cards/adapters use the same following settings:
• Network type: Ad-Hoc
• SSID:_____________________
• Channel: _________________
• wireless standard: IEEE 802.11b, g, b/g or a
• Security:
( ) None
( ) WEP (64bit, 128bit or 256bit key) (ASCII or Hex):________________
5.2 Wireless Security Overview
The following sections introduce different types of wireless security you can set up in the
wireless network.
5.2.1 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.
5.2.2 MAC Address Filter
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.