Asking browsers to cache as aggressively as possible

Question

This is about a web app that serves images. Since the same request will always return the same image, I want the accessing browsers to cache the images as aggressively as po

Answer 1

A few days cache age is very low. You should set it to one year or even more. Of course this might raise problems when the image actually changes but you can solve that by adding a version number to the image and changing the page that references the image to include the path to the new image.

I wrote more about web application caching here: http://patchlog.com/web/7-methods-to-cache-web-applications/