Cisco Cisco Web Security Appliance S380 User Guide

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Cisco AsyncOS for Web User Guide
 
Chapter 9      Classify URLs for Policy Application
  Regular Expressions
In the following example, the regular expression matches files ending in 
.exe
.zip
, and .
bin
 in the 
downloads
 directory.
/downloads/.*\.(exe|zip|bin)
Avoid using regular expressions strings that are redundant because they can cause higher CPU usage on 
the Web Security appliance. A redundant regular expression is one that starts or ends with “.*”. 
Note
You must enclose regular expressions that contain blank spaces or non-alphanumeric characters in 
ASCII quotation marks.