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It is best to create a single access control table and store it on the harddisk
of the LAN administrator station and/or share it with other LAN administrator
stations. You are advised to use only one table for all Radio Link Modules.
For more information refer to
161).
The WEP Encryption functionality allows the wireless system to support up
to four different keys simultaneously. This is in accordance with the 802.11
standard, which defines four so-called "default keys" .
These keys can be used to smooth the transition from the usage of one key
to usage of a next key. The general requirement for two cards to transmit
encrypted between each other is that they share a common key value at the
same key-index number in the 4-key area at the moment of transmission.
The key-index of the key that was used for encryption is transmitted in clear-
text in the header of the message, and will be used at the receiving side to
determine which of the 4 keys to use for decryption.
It is not mandatory that both sides (typically RLM and SIMATIC NET
Industrial Wireless LAN station) have the same active set of 4 keys. As long
as there is one key in common, they can communicate, provided they both
use that common key.
Industrial Ethernet Wireless LAN RLM Manager, CP 1515 Manager
C79000-G8976-C171-01
Creating/Editing an Access Control Table (page
183
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