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Static content caching

The Imperva CDN caches static content, such as HTML files, images or JavaScript resources, so they can be served on demand directly from our globally distributed data centers.


Dynamic content caching

An advanced learning system continuously profiles website resources, gathering intelligence on the frequency with which they are updated. Dynamically generated resources, which rarely change over time, are cached to improve performance without affecting content freshness.

Variable modes

We give you full control and flexibility with respect to caching policies. You can choose from the following predefined caching modes:

Disable caching

No caching is performed. All content is transferred directly from your web server.

Static only

Only content that has been marked by the site’s developer or web server as static (using standard HTTP headers) will be cached.

Static + dynamic

Imperva applies a learning algorithm, which dynamically profiles your site and identifies content that should be cached. If a change in the site is identified, re-learning is triggered. The time period that you set for this option determines how often the cache is refreshed.


All site content is cached. The time period that you set for this option determines how often the cache is refreshed. Aggressive mode is recommended only for a site that doesn’t contain dynamically updated content.

Instant cache purge

Instant cache purge

The Imperva network design supports instant cache purge and rule propagation, either manually or automatically, through the GUI or API.

Once a purge request is made, content is cleared across the Imperva global network in sub-second response time.

Custom caching rules

Custom caching rules

Custom rules allow you to control caching for specific files and file types, as well as set cache policies based on folder paths and URL parameters.

The rules are easily set using the GUI and can be readjusted with just a few clicks of your mouse.

Client-side caching

Client-side caching

Imperva automatically optimizes client-side caching to make sure that as much content as possible is stored locally on the visitor’s desktop or mobile device. This ensures the best possible user experience for repeat visitors.

Asynchronous validation

Asynchronous validation

With asynchronous validation turned on, Imperva serves the cached content before refreshing the cache in the background for subsequent visitors.

Asynchronous validation allows for improved performance, but may impact freshness. The option is turned off by default.

Related Content

Key Resources

O’Reilly: Full Stack Web Performance

O’Reilly: Mastering Full Stack Web Performance

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CDN bootcamp

Free Course to Master Website Performance

Online Course
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