- From: Willy Tarreau <w@1wt.eu>
- Date: Sun, 26 Feb 2012 07:40:25 +0100
- To: Patrik Fältström <patrik@frobbit.se>
- Cc: John C Klensin <john-ietf@jck.com>, Patrik Fältström <paf@frobbit.se>, Andrew Sullivan <ajs@anvilwalrusden.com>, "mnot@mnot.net" <mnot@mnot.net>, IETF Discussion <ietf@ietf.org>, "iesg@ietf.org" <iesg@ietf.org>, "ietf-http-wg@w3.org" <ietf-http-wg@w3.org>
On Fri, Feb 24, 2012 at 05:57:31PM +0100, Patrik Fältström wrote: > I am asking more generally why specifically this DNS issue is so stuck, > because I think that is unfair. We upgrade other protocols... Because in HTTP, anybody can be anywhere. You can have client-side proxies, server-side gateways, load balancers, etc... everyone in this chain may or may not resolve, it's only a matter of configuration and architecture choice. There are plenty of places where clients won't access public resolvers at all and rely on their proxies for this. So you can't make use of DNS to improve these users' experience. Also, DNS is SLLLLOOOOWWWWW. It's fast enough to send a mail. But for HTTP it adds too much latency. Some people in the mobile world would like to be able to configure an explicit proxy on their smartphones in order to avoid a very expensive round trip before fetching an object : at 20 host names on a web page, 300 ms round trip means 6 seconds are lost to resolve these objects if they can't be totally parallelized. DNS suggestion is something going back and forth regularly. I think that people who try to push it hard only see the very simple case where users have a direct low-latency internet connection. The reality is much much different. This well reflected by the fact that in the end, after many proposals, it has still not been adopted ! Regards, Willy
Received on Sunday, 26 February 2012 06:44:12 UTC