- From: 陈智昌 <willchan@chromium.org>
- Date: Tue, 23 Oct 2012 21:12:56 -0700
- To: Mark Nottingham <mnot@mnot.net>
- Cc: "ietf-http-wg@w3.org Group" <ietf-http-wg@w3.org>
On Mon, Oct 22, 2012 at 7:50 PM, Mark Nottingham <mnot@mnot.net> wrote: > > On 23/10/2012, at 1:33 PM, William Chan (陈智昌) <willchan@chromium.org> wrote: > >> Overall, sounds good. I've included some clarifications/questions below. > > [...] > >>> Who's willing to do some experimentation? Specifically, does anyone have access to the code that was used before (IIRC, people bought some ads and inserted some Java to probe the network)? >> >> Do you mean the Chromium HTTP upgrade experiment agl referred to in >> http://www.ietf.org/mail-archive/web/tls/current/msg05593.html? > > No, IIRC there was also some broader experimentation using ads; I'll dig around a bit more. > > Of course, if Chrome (or any other browser) would be interested in running an experiment, we'd love to do that too -- provided we can have input into the design. Is there anything you'd like to change about the design in http://www.ietf.org/mail-archive/web/tls/current/msg05593.html? I'm in general supportive of running experiments, I just don't want to waste our time unless there was something deficient about the previous experiment. Also, I suspect a non-Google experiment would carry more weight :) External validation is good. On that point, at Realtime Conf today, Arnout Kazemier provided a bunch of data on issues with WebSockets deployment. https://speakerdeck.com/3rdeden/realtimeconf-dot-oct-dot-2012. As he says "tl;dl: Always use SSL". > > >>> Does anyone object to us defining such a record (type TBD), as long as it's not the only way to get to HTTP/2 for HTTP URIs? >> >> I'm not sure if my previous emails were taken to indicate "interest" >> here. I forget what I said too :) As long as this is more of an >> optional optimization than anything, I guess I'm OK with it. I'm very >> much concerned about relying on it, due to experiments we have run >> with TXT records that show us noticeably higher failure rates in >> comparison to port 443, higher latency (we'd definitely have to race >> this), and extra DNS queries. > > Yes, I think relying on it would be a mistake, for a variety of reasons. > > >>> 2) Using a response header to hint that HTTP/2 is available on another port. >>> >>> This approach hasn't been talked about in detail yet, but it apparently (as some have noted) has the disadvantage of not upgrading the first interaction, and of requiring a separate cache (and caching model) for this information. >> >> Just to be clear, SRV records also have the disadvantage of not >> upgrading the first interaction, unless you block on the response, >> which Chromium definitely is not going to do unless the environment >> changes such that it doesn't kill performance. > > > I'll leave it to the DNS experts to debate the capabilities and merits here. > > > -- > Mark Nottingham http://www.mnot.net/ > > >
Received on Wednesday, 24 October 2012 04:13:23 UTC