TTL and Invalidations
Explore how AWS CloudFront manages content delivery by using Time-to-Live settings and cache invalidation techniques. Understand how TTL values control cache duration, how cache-control headers influence caching, and how invalidations help deliver fresh content immediately. Discover how versioning can reduce cache invalidation needs and improve content management in high-update scenarios.
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CloudFront’s architecture is centered around caching content at edge locations to enhance content delivery performance and reduce latency for end users. However, this caching mechanism introduces the risk of serving stale data if updates occur at the origin.
To address this challenge, CloudFront employs the concept of Time-to-Live (TTL).
Time-to-Live (TTL)
Time-to-Live (TTL) refers to the duration for which an object is considered valid and cached at edge locations. When an object’s TTL expires, CloudFront initiates an origin fetch to retrieve the latest version of the object from the origin server. If the object has been updated, CloudFront fetches the updated content from the origin server and refreshes its cache. If the object hasn’t been updated, CloudFront continues serving the cached content. This ensures that users receive up-to-date content, promoting a seamless browsing experience.
CloudFront sets a TTL of 24 hours ...