Intel 2200BG, Руководство пользователя

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Using Open authentication, any wireless station can request authentication. The
station that needs to authenticate with another wireless station sends an
authentication management frame that contains the identity of the sending station.
The receiving station or AP will grant any request for authentication. Open
authentication allows any device network access. If no encryption is enabled on the
network, any device that knows the SSID of the access point can gain access to
the network.
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Using Shared Key authentication, each wireless station is assumed to have
received a secret shared key over a secure channel that is independent from the
802.11 wireless network communications channel. Shared key authentication
requires that the client configure a static WEP key. The client access will be
granted only if it passed a challenge based authentication.
Network Keys
When Data Encryption (WEP, CKIP or TKIP) is enabled, a network key is used for
encryption. A network key can be provided for you automatically (for example, it might be
provided on your wireless network adapter, or you can enter it yourself and specify the
key the key length (64-bits or 128-bit), key format (ASCII characters or hexadecimal
digits), and key index (the location where a specific key is stored). The longer the key
length, the more secure the key. Every time the length of a key is increased by one bit,
the number of possible keys double.
Under 802.11, a wireless station can be configured with up to four keys (the key index
values are 1, 2, 3, and 4). When an access point or a wireless station transmits an
encrypted message using a key that is stored in a specific key index, the transmitted
message indicates the key index that was used to encrypt the message body. The
receiving access point or wireless station can then retrieve the key that is stored at the
key index and use it to decode the encrypted message body.
Encryption Static and Dynamic Key Types
802.1x uses two types of encryption keys, static and dynamic. Static encryption keys are
changed manually and are more vulnerable. MD5 authentication only uses static
encryption keys. Dynamic encryption keys are renewed automatically on a periodic basis.
This makes the encryption key(s) more secure. To enable dynamic encryption keys, you
must use 802.1x authentication methods, such as TLS, TTLS, PEAP or LEAP.