THE FOLD / SPAWN / GENESIS BLOCK / THE SLOW START
THE SLOW START
it finds the first thing that broke, not the capacity
1 WHAT IT IS · WHAT IT DOES · FACT OR FICTION
A new connection knows nothing about the path it is on. Slow start finds out by doubling every round trip until something breaks. The name describes where it begins, not how fast it moves.
LIT verified live. A pipe holding 1,000 packets is filled in 10 round trips by doubling; probing one packet at a time would take 1,000 — 100.0× longer. The window at exit is 1,024, so the last doubling overshoots the pipe by 24 packets, 2.4%. Finding the limit cost 1,023 packets sent, which is one less than the window it arrived at.
LIT verified live. A pipe holding 1,000 packets is filled in 10 round trips by doubling; probing one packet at a time would take 1,000 — 100.0× longer. The window at exit is 1,024, so the last doubling overshoots the pipe by 24 packets, 2.4%. Finding the limit cost 1,023 packets sent, which is one less than the window it arrived at.
2 HOW IT WAS WEAVED · AI + HUMAN
Slow start is Van Jacobson’s, from the 1988 response to the NSFNET congestion collapses.
AVAN (AI) published the overshoot next to the speed because they are the same mechanism. Doubling cannot find a limit without crossing it — the algorithm learns the capacity by exceeding it once, and every connection you open pays that 2.4% to discover a number the network already knew.
AVAN (AI) published the overshoot next to the speed because they are the same mechanism. Doubling cannot find a limit without crossing it — the algorithm learns the capacity by exceeding it once, and every connection you open pays that 2.4% to discover a number the network already knew.
3 ONE DIMENSION
Doubling against probing, to the same pipe.
4 TWO DIMENSIONS · INTERACTIVE
Change the pipe and count the round trips.
5 THREE DIMENSIONS + AVAN’S INVERSE
The green forward object: a doubling that has to overshoot.
AVAN’s addition (the inverse-companion): the forward reading is that slow start finds the capacity quickly. The inverse is that it never finds the capacity at all — it finds the first thing that broke. Loss is the only signal, so what the algorithm learns is the location of a boundary, not its size, and a link that drops for any other reason teaches it a number that was never about congestion. Read backwards, every connection begins by asking a question it can only get one kind of answer to, and then treats that answer as the truth about the path.
LIT a pipe holding 1,000 packets is filled in 10 round trips by doubling against 1,000 for one-at-a-time probing, which is 100.0 times longer, and the window at exit is 1,024 so the last doubling overshoots by 24 packets or 2.4%, having sent 1,023 packets to find a limit it could only locate by crossing it
FIG Slow start is Van Jacobson's, from the 1988 response to the NSFNET congestion collapses. AVAN published the overshoot next to the speed because they are the same mechanism. Doubling cannot find a limit without crossing it - the algorithm learns the capacity by exceeding it once, and every connection you open pays that 2.4% to discover a number the network already knew.
FIG Slow start is Van Jacobson's, from the 1988 response to the NSFNET congestion collapses. AVAN published the overshoot next to the speed because they are the same mechanism. Doubling cannot find a limit without crossing it - the algorithm learns the capacity by exceeding it once, and every connection you open pays that 2.4% to discover a number the network already knew.
◆ sealed .dlw.fold → folded to ROOT_0 · a sphere of GENESIS BLOCK · David Lee Wise (ROOT0), with AVAN