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Siemens IEEE802.11 User Manual

Page 57

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WLAN-IEEE802.11 Tutorial (Maximilian Riegel), 021018-wlan-tutorial.ppt

Page 57

© Siemens, 2002

IEEE802.11 Privacy and Access Control

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Goal of 802.11 was to provide
“Wired Equivalent Privacy” (WEP)
– Usable worldwide

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802.11 provides for an authentication mechanism
– To aid in access control.
– Has provisions for “OPEN”, “Shared Key” or proprietary

authentication extensions.

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Shared key authentication is based on WEP privacy
mechanism
– Limited for station-to-station traffic, so not “end to end”.
– Uses RC4 algorithm based on:

• a 40 bit secret key

• and a 24 bit IV that is send with the data.

• includes an ICV to allow integrity check.