CHAPT ER
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Cisco Intrusion Prevention System Sensor CLI Configuration Guide for IPS 7.2
OL-29168-01
5
Configuring Virtual Sensors
This chapter explains the function of the Analysis Engine and how to create, edit, and delete virtual
sensors. It also explains how to assign interfaces to a virtual sensor. It contains the following sections:
Virtual Sensor Notes and Caveats, page 5-1
Understanding the Analysis Engine, page 5-2
Understanding Virtual Sensors, page5-2
Advantages and Restrictions of Virtualization, page5-2
Inline TCP Session Tracking Mode, page 5-3
Normalization and Inline TCP Evasion Protection Mode, page 5-4
HTTP Advanced Decoding, page 5-4
Adding, Editing, and Deleting Virtual Sensors, page 5-4
Configuring Global Variables, page5-12

Virtual Sensor Notes and Caveats

The following notes and caveats apply to configuring the virtual sensor:
The Cisco IPS does not support more than four virtual se nsors. You cannot delete the default virtual
sensor vs0.
The ASA IPS modules (ASA 5500-X IPS SSP and A SA 5585-X IPS SSP) do not support the inline
TCP session tracking mode.
For the ASA IPS modules (ASA 5500-X IPS SSP and ASA 5585-X IPS SSP), normalization is
performed by the adaptive security appliance and not the IPS.
Anomaly detection is disabled by default. You must enable it to configure or apply an anomaly
detection policy. Enabling anomaly detection results in a decrease in performance.