Additional Wep Key Security Features; Message Integrity Check (Mic) - Cisco AIR-PCM352 - Aironet 350 Series 11Mbps Wireless LAN PC Card Adapter Installation And Configuration Manual

Chapter 5 Configuring the Client Adapter
5.
6.
This feature does not need to be enabled on the client adapter or access point; it is supported
Note
automatically in the firmware of both devices. However, both the client and access point must use these
firmware versions or later.

Additional WEP Key Security Features

The three security features discussed in this section (MIC, TKIP, and broadcast key rotation) are
designed to prevent sophisticated attacks on your wireless network's WEP keys. These features do not
need to be enabled on the client adapter; they are supported automatically in the client adapter driver and
firmware. However, they must be enabled on the access point.
Note Access point firmware version 11.10T or later is required to enable these security features. Refer to the
software configuration guide for your access point for instructions on enabling these features.

Message Integrity Check (MIC)

MIC prevents bit-flip attacks on encrypted packets. During a bit-flip attack, an intruder intercepts an
encrypted message, alters it slightly, and retransmits it, and the receiver accepts the retransmitted
message as legitimate. MIC adds a few bytes to each packet to make the packets tamper-proof.
The ACU Status screen indicates if MIC is supported by the client adapter's driver and is enabled on the
access point. See
Figure 5-2
OL-1375-04
The client sends the MAC address of access point A and the reason code for the failure to access
point B.
Access point B logs the failure in the system log.
Figure 5-2.
ACU Status Screen
Cisco Aironet 350 Series Wireless LAN Client Adapters Installation and Configuration Guide for Windows CE
Overview of Security Features
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