How to Boost the Performance of Your Website to Promote it in Search Engines – Fifth PartWednesday, October 14, 2009 2:06
A mechanism for browsers and servers to determine if the component that is in the browser’s cache is in match with the other on the origin server is entity tags of Etags. An Etag is used to identify and validate a specific version of webpage component. The origin server uses the Etag to specify the Etag of a component. The browser sends back the Etag to the origin server using the If-None-Match header. On matching of the Etags, a 304 status code returns and reduces the response by 12195 bytes.
Etags are unique to a particular server only when they are constructed using typical attributes. If the Etag on the original server and the Etag on a different server do not match, users do not receive the 304 response. Rather, they get a 200 response with the data for webpage component. It is not a serious problem, if your site is hosted on one server. If the website is hosted on multiple servers, your users will experience slower pages. Webpage components on websites with a higher load are not efficiently cacheable. Removing Etags is better to decrease the size of the HTTP headers in both requests and responses.
The plate is heaped with tips on speeding up website performance. So, be patience to wait for my next blog….