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If you are on high-speed connections, then the the congestion window issue is most significant for you.
if you have an overloaded link at some point in your path, then bufferbloat is your biggest problem.
Posted Feb 11, 2011 0:28 UTC (Fri) by Lennie (subscriber, #49641)
This could induce or increase the effect of bufferbloat
Posted Feb 11, 2011 6:31 UTC (Fri) by butlerm (subscriber, #13312)
Google has a proposal to fix this with a mid layer multi-stream protocol between HTTP and TCP. Even better would be a proper multi-streaming transport protocol like SCTP, but not so intelligent NAT devices appear to have killed that option for the time being. Meanwhile, Google Chrome appears to restrict the number of connections it uses pretty severely, which makes it noticeably slower than Internet Explorer on some applications which are not at all bandwidth constrained.
Posted Feb 11, 2011 10:08 UTC (Fri) by Lennie (subscriber, #49641)
Also it is a model which might not yet fit wel with some current webservers. It won't be an easy module to add to Apache for example. A proxy could work though.
Ironicly of all the currently deployed browsers, IE6 and IE7 from Microsoft are actually open the least amount of connections and the one with the most connections: ie8 (and I presume ie9)
Proxies, multi-streaming, wireless, bufferbloat
Posted Feb 11, 2011 13:41 UTC (Fri) by mtaht (✭ supporter ✭, #11087)
Posted Feb 12, 2011 6:53 UTC (Sat) by dtlin (✭ supporter ✭, #36537)
Posted Feb 12, 2011 12:04 UTC (Sat) by Lennie (subscriber, #49641)
I'm talking about this one, it's just sitting there (atleast that is what it looks like to me):
Without something at IETF or something which looks mostly final why would other browser vendors and webserver people implement it ? Without atleast that, it is useless.
This is the last status:
Who knows, maybe this is the reason why:
He is just to busy and there isn't anyone else to help him ?
Posted Feb 16, 2011 17:22 UTC (Wed) by mbelshe (guest, #72948)
Well, I'm glad you guys are interested. I assure you that we're still hard at work on it. It just takes time.
This year, we'll be much more active and look to get IETF support. Unfortunately, some things just can't be rushed.
Posted Feb 17, 2011 9:28 UTC (Thu) by Lennie (subscriber, #49641)
SPDY sounds to me like the right way, instead of adding more TCP-connections all with a larger initial windows size.
Bufferbloat is a different problem, but adding more TCP-connections with larger initial window sizes wouldn't help either.
SPDY seems to also be about delivering fast TLS. That would help a lot, we've seen to many problems with cookies getting picked up by others.
Maybe we don't want to use it for certain static files, atleast that is what people think when they see what is happening with Google SSL/Google Images. Maybe it is just a loadbalancer/TLS-sessions problem, it breaks TLS Session Resumption ?
If browsers that use SPDY are shown to be faster and people flock to it, it will also help spread the support for SNI. Although I think people who use IE on XP are probably not speedfreaks anyway.
But the more reasons people have not use IE on XP the better. :-)
Posted Feb 16, 2011 17:18 UTC (Wed) by mbelshe (guest, #72948)
SCTP does centralize cwnd across all open streams, but it uses the same core algorithms as TCP and fails to address the initial burst. Unless the initial burst is increased, SCTP is slower than HTTP over lots of TCP connections out of the gate. This is measurable and demonstrable.
Oh, and SCTP doesn't work over NAT. So still waiting for IPv6.
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