HTTP2

HTTP/2 (originally named HTTP/2.0) is a major revision of the HTTP network protocol used by the World Wide Web. It was derived from the earlier experimental SPDY protocol, originally developed by Google. HTTP/2 was developed by the Hypertext Transfer Protocol working group httpbis (where means "second") of the Internet Engineering Task Force. HTTP/2 is the first new version of HTTP since HTTP 1.1, which was standardized in RFC 2068 in 1997. The Working Group presented HTTP/2 to IESG for consideration as a Proposed Standard in December 2014, and IESG approved it to publish as Proposed Standard on February 17, 2015. The HTTP/2 specification was published as RFC 7540 in May 2015.

The standardization effort was supported by Chrome, Opera, Firefox,Internet Explorer 11, Safari, Amazon Silk, and Edge browsers. Most major browsers by the end of 2015.

According to W3Techs, as of May 2017^[update], 13.7% of the top 10 million websites supported HTTP/2.

The working group charter mentions several goals and issues of concern:

The proposed changes do not require any changes to how existing web applications work, but new applications can take advantage of new features for increased speed.

HTTP/2 leaves most of HTTP 1.1's high-level syntax, such as methods, status codes, header fields, and URIs, the same. What's new is how the data is framed and transported between the client and the server.

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