HTTP/2 roadmap

[Maxim Dounin]

Hello!

On Fri, Mar 11, 2016 at 02:40:34PM +0000, Phil Lello wrote:

> Hi,
> 
> What's the best place to find details on planned features for HTTP/2
> support?
> 
> I've only been looking at HTTP/2 for a few days, so forgive me if this is
> already covered.
> 
> It seems pretty obvious to me that it provides an opportunity for
> potentially significant performance gains if changes are made to the xCGI
> model, and potentially web applications.
> 
> Specifically, since there is a quasi-persistent [1] connection between a
> browser and a server, serialisation of a session object between page
> requests is no longer necessary, and it can become bound to the transport
> layer - whilst this may seem to introduce possible race conditions between
> pages, this is no different from concurrent requests on the same session
> under HTTP/1.x.

This is not going to work for multiple reasons, at least:

- connections can be broken for unrelated reasons (network 
  changes, server reloads, whatever);

- transport layer is not guaranteed to be bound to a particular 
  client, and can be used by many different clients instead (e.g., 
  when used by proxy servers);

- there may be intermediate servers and different protocols 
  involved, so from backend point of view there will be multiple 
  different connections;

We've already seen how connection-oriented model [does not] work 
for Microsoft with their NTLM authentication scheme.  Don't try to 
repeat their mistakes.

> A secondary requirement is a mechanism to implement server-push, so that
> <language-of-choice> can specify page dependencies, rather than requiring
> inspection of content within the server.
> 
> Is any work currently being done in this direction?

No.

-- 
Maxim Dounin
http://nginx.org/