Large number of web servers today, run Apache HTTP Server. It may be possible that the virtual private server, cloud hosting server or others, where your websites are hosted, might be running Apache. Using certain techniques, one can reduce the bandwidth consumed by the Apache.
Using the Expire Headers setting one can easily decrease the bandwidth consumption. What it does is, it amalgamates with the user agent ie. a web browser and gives instructions about the necessity of refreshing the cache for a web-page. An advantage of caching is that, the web browser is not required to keep reloading the website at each of its visits, this is specifically required for sites that has high volume of graphics. Hence, even the dynamic websites can take advantage from from caching.
With the use of expiry tags, users speed up their website and increase the response rate. If a website has static images, one can choose to set long expiry tags, this is due to the basic fact that they are less expected to change. Incase you intend to update the RSS feed of a website after every 2 hours, you can go about setting the below given expiry tags :
ExpiresDefault “access plus 2 hours”
mod_expires directive can be alternately used in your Apache configuration, virtual host configuration, and the .htaccess files.