Typically, web applications contain a large number of URLs in which, the parts of the URL are static/same. When Learning is enabled for a web application on the Barracuda Web Application Firewall, URL profiles and parameter profiles are created based on the traffic processed by the Barracuda Web Application Firewall according to a set of matching criteria specified on the WEBSITES > Adaptive Profiling page, in the Adaptive Profiling section. In this scenario, the Barracuda Web Application Firewall create a URL profile for each URL, which may result in populating a large number of profiles with the same parameters.
For example: Consider www.foobar.com is a web application for which Learning was enabled and resulted in the following URL profiles:
Managing a huge number of profiles having the same security requirement can become unnecessarily complex to handle. You can handle such issues by categorizing specific URL spaces and coalescing multiple URL profiles into one. The URL profiles mentioned in the example above can be coalesced as:
- Start Token: /abc/example
- End Delimiter: period/dot (.)
- Start Token is configured with the URL path substring that remains constant in all URLs mentioned in the example above.
- End Delimiter is configured with the character whose occurrence after the Start Token denotes the end of the variable portion of the URL.
This will coalesce all the URL profiles into one URL profile i.e. /abc/example*.html. Any request sent to /abc/example1.html to /abc/example200.html will match the /abc/example*.html URL profile.
Using URL Optimizers
You can configure URL optimizers in any of the following two ways:
- If you have prior knowledge of the directory structure of the web application, configure URL optimizers before enabling Learning for the web application.
- Enable Learning for the web application and allow the Barracuda Web Application Firewall to create profiles for the web application. This may result in creating multiple URL profiles with identifiable patterns. Note the created patterns, configure the URL optimizers and click Merge to coalesce multiple URL profiles into one.
Steps to Add a URL Optimizer
- Go to the WEBSITES > Adaptive Profiling page.
- In the URL Optimizers section, click Add next to the service for which you want to add URL optimizer. The Create URL Profile Optimizer page appears.
- In the Create URL Profile Optimizer page, specify values for Optimizer Name, Start Token and End Delimiter:
- Click Save.