After more than two years of discussion, over 200 design issues, 17 drafts, and 30 implementations, the HTTP/2 and HPACK specifications have now been approved by the IETF’s steering group for publication as standards-track RFCs. The result is that HTTP/2 will help provide faster user experience for browsing, reduce the amount of bandwidth required, and make the use of secure connections easier.
The HTTP Working Group began work on HTTP/2 in 2012 by selecting Google’s SPDY protocol as the starting point, holding a series of six interim meetings to incorporate community feedback. This resulted in substantial changes to the format of the protocol, its compression scheme, and its mapping to the semantics of HTTP.
The resulting protocol is designed to allow a seamless switch between HTTP/1 and HTTP/2, with minimal changes to applications and APIs, while at the same time offering improved performance and better use of network resources. Web users largely will be able to benefit from the improvements offered by HTTP/2 without having to do anything different.
A key point in the protocol development process was the iteration the working group did between protocol updates, and implementations and testing. Certain draft protocol versions were labelled by the working group as “implementation drafts”, and the participants — many web browser and web server providers — updated their implementations and tested out the protocol changes. Most of the interim meetings included part of a day spent on hands-on interoperability testing and discussion. The result is a thoroughly validated protocol that has been shown to interoperate and that meets the needs of many major stakeholders.
The HTTP/2 work specifically embodies the key IETF tenet about the value of “rough consensus and running code.”
Mark Nottingham, HTTPBIS Working Group Chair and Barry Leiba, Applications Area Director