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Security
Wired Equivalent Privacy (WEP) Encryption
The WEP feature encrypts all data transmitted within the wireless network. The encryption
uses the RC4 algorithm as defined in the IEEE 802.11 Wired Equivalent Privacy standard.
The RoamAbout devices can be configured with four encryption keys. Each key is placed
in a specific position (Key 1, Key 2, Key 3, or Key 4). You select one key to encrypt
transmitted data. To decipher the data, the receiving wireless device must have the key used
to encrypt the data in the same position as the sending device.
The receiving device can transmit data back to the sending device using a different key for
transmission, as long as the other device has the transmitting key in the same position. In
Figure 2-3, the AP uses Key 1 to encrypt transmitted data, which the client can decipher.
The client uses Key 2 to encrypt transmitted data, which the AP can decipher. If the AP
uses Key 3 to encrypt transmitted data, it cannot be deciphered by the client. The Bobss key
is Key 3 on the AP but Key 4 on the client.
Figure 2-3: Using Encryption
In a wireless infrastructure network, you can configure the APs to:
•Only accept encrypted data from clients. Only clients that have the correct encryption
keys can participate in this network.
•Accept encrypted data from clients with encryption enabled, and unencrypted data
from clients without encryption enabled. This allows clients who require security to
use encryption without preventing other clients from using the network.
In a LAN-to-LAN configuration, use encryption to have a secure wireless link. In an ad-hoc
network, use encryption to prevent uninvited users from joining the network.
NOTE: Broadcast and multicast messages are not encrypted.
NOTE
Key 1 = Je3ff
Key 2 = Vicki
Key 3 = Bobss
Key 4 = [No Entry]
Key 1 = Je3ff
Key 2 = Vicki
Key 3 = Freds
Key 4 = Bobss
Transmit Key = 2
Transmit Key = 1