[Bloat] About Stochastic Fair Blue (SFB)

[Juliusz Chroboczek]

Hi again,

In his series of articles, Jim has concentrated on router-based
solutions to delay issues.  He mentioned AQM policies in routers, and
notably the venerable RED.

AQMs are designed to achieve two different (but not necessarily
contradictory) goals: to improve the behaviour of the traffic (notably
by reducing the amount of buffering, which is what we're concerned about
here), and to improve fairness.  For example, RED is mostly concerned
with the former, while CHOKe is only concerned with the latter.

One AQM that attempts both is Stochastic Fair a stochastically-fair
variant of BLUE [1].  In addition to reducing buffer size and enforcing
rough inter-flow fairness, SFB will reliably detect unresponsive flows
and rate-limit them.

In order to experiment with SFB, I've implemented it for Linux a couple
of years ago [2].  Unfortunately, I've given up for now on trying to get
it into the mainline kernel, and I'm not sure I want to try again [3].

--Juliusz

[1] W. Feng, D. Kandlur, D. Saha, K. Shin. Blue: A New Class of Active
    Queue Management Algorithms. U. Michigan CSE-TR-387-99, April 1999.
    http://www.thefengs.com/wuchang/blue/CSE-TR-387-99.pdf
[2] http://www.pps.jussieu.fr/~jch/software/sfb/
[3] http://article.gmane.org/gmane.linux.network/183813