HAQM CloudFront Lowers Minimum Content Expiration Period

Posted on: Mar 19, 2012

We're excited to announce that you can now use HAQM CloudFront for frequently changing content. Before today, HAQM CloudFront’s edge locations cached objects for a minimum of 60 minutes. Effective today, we’ve removed the sixty minute minimum expiration period (also known as “time-to-live” or TTL) from HAQM CloudFront. With this change, you have the ability to configure a minimum TTL for all objects in your distribution using the HAQM CloudFront API. The minimum TTL value may be as short as 0 seconds. You can then set the TTL for each file by setting the cache control header on your file in the origin. HAQM CloudFront uses cache control headers to determine how frequently each edge location gets an updated version of the file from the origin. Note that our default behavior isn’t changing; if no cache control header is set, each edge location will continue to use an expiration period of 24 hours before checking the origin for changes to that file. You can also continue to use HAQM CloudFront's Invalidation feature to expire a file sooner than the TTL set on that file.

You can learn more about the new expiration period policy in the HAQM CloudFront Developer Guide or by visiting the HAQM CloudFront product page.