Mark Nottingham, the chair of the HTTP working group overseeing the development of of HTTP/2, has announced that the standard is complete and headed to the RFC editor for tweaks before publication as a standard.
HTTP is one of the fundamental technologies underlying the web, and it hasn’t seen a comprehensive upgrade since 1999, when HTTP 1.1 was introduced.
The web has changed enormously since 1999, but the technology that makes the web possible changes achingly slowly. While the tools used by developers and designers for creating sites is constantly moving forward, they have still had to contend with an protocol that was created back when dial-up was all the rage and blinking text was considered a bold design choice.
HTTP/2 is a protocol built for the modern web and it bringsnumber of advancements that will make the web faster. HTTP/2 is based on an experimental protocol called SPDY(pronounced speedy). SPDY was Google’s attempt to overcome the limitations of HTTP; it’s been adopted by most major browser developers and is used on many Google properties as well as sites like Facebook.
What’s so great about HTTP/2? One of the major problems with the way HTTP/1 works is that it thinks of a web page as a single stream of data, which hasn’t been true for some time. By forcing browsers to make new connections for requests, they become something to be avoided because connections take time.
HTTP/2 introduces multiplexing so that many requests can be made on the same connection, making them much more efficient. Additional new features include server push, so servers can send necessary page components without waiting for the browser to ask for them; and header compression, which prevents headers from dominating bandwidth use.
One thing that HTTP/2 was expected to include, but does not, is mandatory encryption. It was originally intended that HTTP/2 would only work over encrypted connections: if a site wanted the speed bump, they had to provide secure connections. It appears that at the behest of some industry members — proxy providers like ISPs, most likely — part of the standard has been removed. In practical terms, it shouldn’t have much impact because both Google and Firefox intend to implement HTTP/2 so that it only works over encrypted connections anyway. The browser manufacturers intend to slip encryption in by the back door because they failed to get it in through the front.
It’s likely that major browser developers will implement HTTP/2 support soon. The Chromium project has announced that version 40 of Chromium — the open source browser on which Google Chrome is based — will include support for HTTP/2 and drop support for SPDY, but these things move slowly, and it’s more than likely that the majority of sites on the web stick with HTTP/2 for the foreseeable future.