- From: Greg Wilkins <gregw@intalio.com>
- Date: Tue, 19 Aug 2014 09:55:04 +1000
- To: Simone Bordet <sbordet@intalio.com>
- Cc: HTTP Working Group <ietf-http-wg@w3.org>
- Message-ID: <CAH_y2NHwVay7ZLSh16V8eB0tmyLQS_fyvdRbUhifHv7XCWdB0w@mail.gmail.com>
Note that there is a thread on the Servlet EG list regarding an API for push: https://java.net/projects/servlet-spec/lists/jsr340-experts/archive/2014-08/message/1 where I've been asked some questions to describe "the rationalization used by the httpbis wg" Since I can't speak for the WG, I thought I'd echo my thoughts here regarding the push mechanism to check that I'm not misrepresenting anything: - Push is a server-side coordinated mechanism in as much as the server must decide to push a resourced based only on information that it already has. Specifically h2 provides no information on the contents or status of downstream caches. - Servers are free to innovate push strategies, with some of the following having been suggested: - Use knowledge from the web application/framework to determine what are associated resources. - Use heuristics derived from referrer headers and timing to infer what are associated resources - Use sessions to track what resources a client has requested/received to avoid unnecessary pushes - Use the presence of if-modified headers to infer the status of a client cache to avoid unnecessary pushes. - There are no functional problems other than increased latency of not pushing an associated resource - There are no functional problems other than wasted bandwidth of pushing an unnecessary resource: - Clients can reset a pushed stream if they determine it is unnecessary. Thus is a server attempts to push a resource that is already cached by the client, a RST will prevent wasting too much bandwidth. Hopefully nothing controversial or misrepresented there? cheers On 18 August 2014 18:57, Simone Bordet <sbordet@intalio.com> wrote: > Hi, > > the Jetty team has deployed h2-14 with HTTP/2 Push functionality on > https://webtide.com, see > https://webtide.com/http2-push-with-experimental-servlet-api/. > > We are very interested in comments about how to make HTTP/2 Push > better, so please try it out and tell us (also see discussion bullets > towards the end of blog post). > > Thanks ! > > -- > Simone Bordet > ---- > http://cometd.org > http://webtide.com > http://intalio.com > Developer advice, training, services and support > from the Jetty & CometD experts. > Intalio, the modern way to build business applications. > > -- Greg Wilkins <gregw@intalio.com> http://eclipse.org/jetty HTTP, SPDY, Websocket server and client that scales http://www.webtide.com advice and support for jetty and cometd.
Received on Monday, 18 August 2014 23:55:32 UTC