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In 2009 Google presented its alternative to HTTP/1.1, namely SPDY. The most critical point of the old HTTP version was and still is the fact that the transfer protocol unnecessarily slows down the most modern complex sites. In fact, for example, using the HTTP/1.1 protocol, a new TCP/IP connection must be established for each single image. With the SPDY protocol Google has solved this problem by multiplexing the transmissions. In this way, using a single TCP/IP connection, many types of documents can be sent. The Internet Engineering Task Force (IETF) started work on the development of HTTP/2 in 2012, based on the Google protocol. Since the implementations of the SPDY protocol contain numerous errors and especially security holes, important changes have been made and this has led the HTTP/2 to distance itself considerably from the SPDY protocol.

HTTP/2 is retroactively compatible, so it’s not a problem if your server or browser still works with the old HTTP/1.1 standard. The option planned later for HTTP/2 to use the standard TLS encryption protocol has not been integrated into the final version.

A special feature of HTTP/1.1 has already been mentioned: a separate TCP/IP connection must be established each time to transfer different elements of the page such as images, JavaScript or CSS files to the client. Instead, HTTP/2 applies, like its SPDY model, a multiplexing process, so that the complete website is loaded into a single connection. In addition, the server now has the ability to re-submit the expected response data to the client without being requested (push server). Again, using the HTTP/2 protocol, the packages of the website components are sent according to priority, for example, the elements responsible for the structure of the site are transmitted first. The HTTP header is sent considerably compressed compared to the HTTP/1.1 so that no unnecessary information is communicated. Another novelty is the use of binary code (instead of text files) for communication, which makes it easier and safer.

Here are all the news about HTTP/2 at a glance:

  • One single TCP/IP connection per website
  • Multiplexing process for exchanging collected data
  • Exchange of information using binary code
  • Reduced HTTP header
  • Push server for predictable response requests
  • Priority to the most important page elements

HTTP/2 protocol is currently available on all Hosting packages.