I am setting up a CDN for my website, I found the following sample for adding to the 'httpd.conf' file, this is used to adjust the cache-time for client and CDN:
ExpiresActive On
ExpiresByType image/gif "access plus 1 year"
ExpiresByType image/jpeg "access plus 1 year"
ExpiresByType image/x-icon "access plus 1 year"
ExpiresByType image/png "access plus 1 year"
ExpiresByType text/css "access plus 1 year"
ExpiresByType text/js "access plus 1 year"
ExpiresByType application/x-javascript "access plus 1 year"
ExpiresByType application/javascript "access plus 1 year"
ExpiresByType application/x-shockwave-flash "access plus 1 year"
<FilesMatch "\.(gif|jpe?g|png|ico|css|js|swf)$">
Header set Cache-Control "s-maxage=600"
</FilesMatch>
Now suppose I updated an image file, the CDN (s-maxage=600) would refresh in 600 seconds, but how about the client? Since 'max-age' is set to 1 year, if client re-visit my web, does it still send HTTP request to check for updated contents and so download the new version? How does this work actually?
Thanks!!