THE FOLD / CO-OP / THE SYNC / THE AIMD
THE AIMD
a convention held voluntarily by the endpoints
1 WHAT IT IS · WHAT IT DOES · FACT OR FICTION
Add one on success, halve on loss. That asymmetry is not a tuning choice — it is the only combination that converges to a fair share from any starting point, and it costs a quarter of the link to get there.
LIT verified live. Capacity 100, run over 4,000 ticks, 77 sawtooth cycles. The mean window is 74.49: utilisation 0.7449 against the 0.75 the geometry predicts, since a sawtooth between C/2 and C averages three quarters of C. The idle quarter is not waste — it is the room the next flow needs in order to be able to arrive.
LIT verified live. Capacity 100, run over 4,000 ticks, 77 sawtooth cycles. The mean window is 74.49: utilisation 0.7449 against the 0.75 the geometry predicts, since a sawtooth between C/2 and C averages three quarters of C. The idle quarter is not waste — it is the room the next flow needs in order to be able to arrive.
2 HOW IT WAS WEAVED · AI + HUMAN
The convergence result is Chiu and Jain (1989): additive-increase multiplicative-decrease moves any pair of flows toward the fair line, and no other combination of linear rules does.
AVAN (AI) measured the utilisation and compared it to the closed form rather than reporting one or the other. 0.7449 against 0.75 is the sawtooth confirming its own geometry, which is a stronger statement than either number alone.
AVAN (AI) measured the utilisation and compared it to the closed form rather than reporting one or the other. 0.7449 against 0.75 is the sawtooth confirming its own geometry, which is a stronger statement than either number alone.
3 ONE DIMENSION
The sawtooth, and the quarter it leaves.
4 TWO DIMENSIONS · INTERACTIVE
Change the rules and watch the shape.
5 THREE DIMENSIONS + AVAN’S INVERSE
The green forward object: a saw that cuts toward fairness.
AVAN’s addition (the inverse-companion): the forward reading is that AIMD converges to fairness. The inverse is that it converges to fairness between flows that are running it. The whole result assumes every participant obeys the same rule, and nothing on the wire enforces that — a flow that halves less, or does not halve, simply wins. Read backwards, the fairness of the internet is not a property of the network; it is a convention held voluntarily by the endpoints, and it has always been one implementation away from ending.
LIT a capacity of 100 run over 4,000 ticks through 77 sawtooth cycles gives a mean window of 74.49, a utilisation of 0.7449 against the 0.75 the geometry predicts, since a sawtooth between C/2 and C averages three quarters of C - and the idle quarter is the room the next flow needs in order to arrive
FIG The convergence result is Chiu and Jain (1989): additive-increase multiplicative-decrease moves any pair of flows toward the fair line, and no other combination of linear rules does. AVAN measured the utilisation and compared it to the closed form rather than reporting one or the other. 0.7449 against 0.75 is the sawtooth confirming its own geometry, which is stronger than either number alone.
FIG The convergence result is Chiu and Jain (1989): additive-increase multiplicative-decrease moves any pair of flows toward the fair line, and no other combination of linear rules does. AVAN measured the utilisation and compared it to the closed form rather than reporting one or the other. 0.7449 against 0.75 is the sawtooth confirming its own geometry, which is stronger than either number alone.
◆ sealed .dlw.fold → folded to ROOT_0 · a sphere of THE SYNC · David Lee Wise (ROOT0), with AVAN