HTTP Header Check

Http head tests can be very powerful once you understood how they work. Transferred data via internet is send via the hypertext transfer protocol (http) in almost every case. When using http there should always be a header and a body. The header includes some meta data that is important for a website. Those meta information can be used to fasten up a website by defining transfer parameters.

There are standard headers that can be found on almost every website and are easy to test.

• Caching – The most powerful thing you can do with http headers is to define the caching behaviour. This can be done via a lot of options. One of the most common is the max-age header. It defines how long a browser is allowed to store an answer.

• GZip – When transfering the content through the world wide web it can be very useful to compress the data. This is done via the Content-Encoding header with the gzip value. This value tells the browser that the content must be decompressed after the receiving.

• Vary – When building high performance websites it is important to have the right caching concept. The vary header tells the browser or other caching layers if the request is equal to another. If the vary value is for example accept-encoding the browser knows that if the url is the same but the content-encoding varies it is not allowed to cache.