[Bloat] Random idea in reaction to all the discussion of TCPflavours - timestamps?

[Dave Täht]

Fred Baker <fred at cisco.com> writes:

> On Mar 17, 2011, at 5:05 AM, Fred Baker wrote:
>
>> I'm very much in favor of ECN, which in all of the tests I have done has proven very effective at limiting queues to the knee. I'm also in favor of delay-based TCPs like CalTech FAST and the Hamilton and CAIA models; FAST tunes to having a small amount of data continuously in queue at the bottleneck, and Hamilton/CAIA tunes to a small bottleneck. The problem tends to be that the "TCP Mafia" - poorly named, but a smallish set of people who actually control widely-used TCP implementations - tend to very much believe in the loss-based model, in part because of poor performance from past delay-based implementations like Vegas and in part due to IPR concerns. Also, commercial interests like Google are pushing very hard for fast delivery of content, which is what is behind Linux' recent change to set the initial window segments. 
>
> I didn't say, and should have said: I'm also in favor of AQM in any form; I prefer marking to dropping, but both are signals to the end system. The issue is that we need the right mark/drop rate, and the algorithms are neither trivial nor (if the fact that after 20+ years Van and Kathy haven't yet published a red-lite paper they're happy with is any indication) well documented in the general case.

A mea culpa from a former ASIC designer, which discusses the
relationship between propagation delay, burstiness, and the real need
for something like RED, and why ASIC designers didn't make it more of a
priority.

"Our biggest mistake was in making queue management optional, and making it scary."

Really well explained, with good diagrams, too.

http://codingrelic.geekhold.com/2011/03/random-early-mea-culpa.html


-- 
Dave Taht
http://nex-6.taht.net