Cisco Cisco 5520 Wireless Controller Guida Alla Progettazione

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Chapter 1      Cisco Adaptive wIPS Management Deployment Guide, Release 8.0
  Adaptive WIPS Management Best Practices
Blacklist
Different from the auto-immune, blacklist is a more aggressive mitigation action to deauthenticate the 
identified attacking device if it is connected first; ignore all traffic from it afterwards as long as it is on 
the blacklist. Currently, the following attacks support blacklist action:
Suspicious after-hours traffic detected
Fake DHCP server detected
Unauthorized association by vendor list
DNS Tunnel bypass detected 
ICMP Tunnel bypass detected
Containment
Containment action in WIPS attacks is similar to rogue AP containment. It is designed to initiate 
containment on SSID-related attacks to prevent legitimate clients connecting to those SSIDs set up by 
attackers. Currently, the following attacks support for containment action:
Soft AP or Host AP Detected 
Airsnarf Attack Detected 
Honeypot AP Detected 
Hotspotter Tool Detected 
Karma Tool Detected 
Device Broadcast XSS SSID
Threshold
Some of the aWIPS alarms are threshold-based, that is, once the frames/packets match over the threshold 
in a sampling period, the alarms are triggered. A sampling period in Cisco WIPS is one minute, which 
is accumulated dwell time on a channel for WIPS APs. 
An AP in local mode with wIPS spends only 50 ms for off-channel scanning; it will take a long time if 
the attacks are off-channel. This is why ELM only provides the best effort with regard to off-channels 
attacks. It is recommended to use monitoring mode (MM) AP to detect off-channel attacks. On the other 
hand, because ELM is on operating channel most of time, it detects on-channel attacks much faster than 
MM AP. 
To get the best output, ELM AP with WSM module is the recommended solution for WIPS deployment. 
Threshold-based alarms tend to cause more false positives compared to non threshold-based ones. But 
for some of them, the accuracy of alarms can be increased when out of sequence (OOS) logic is also 
taken into consideration. Therefore, these alarms are subjects for administrators to monitor, review, and 
fine-tune.
Fidelity
Fidelity is one key attribute missing in previous Cisco aWIPS documentations or aWIPS user interfaces. 
It represents a measure of confidence level in signature accuracy. The fidelity level of WIPS alarms can 
be categorized into the five categories with regard to accuracy percentage as follows:
Very High > 95% 
High > 80%