The KenRadio RSS Feed now has caching. I am using the If-Modified-Since header to determine whether the full RSS file needs to be send or a “304 Not Modified” is sufficient thus conserving bandwidth. The LastModifiedTime is the upload time of the latest show. This step became necessary because now all shows in the RSS feed have an encoded content. But the whole thing only started to work once I used a response.clearheaders. Without it setting the LastModifiedTime does not work.