Each interval, it will try one variation. So if you select 16 variations then it will take 16 intervals before you get back to the first one. i think that, as we showed in [0], 16 may be low for typical paths. [0] - https://ripe66.ripe.net/presentations/128-130513.tokyo-ping.pdf In that presentation I cannot find any clear evidence that that there are more than 16 unique paths. But maybe I missed something.
apologies. i guess it was in the paper not the preso, uppr right of page 3 of C. Pelsser, L. Cittadini, S. Vissicchio, and R. Bush, From Paris to Tokyo: On the Suitability of Ping to Measure Latency, 2013 Internet Measurement Conference. <http://conferences.sigcomm.org/imc/2013/papers/imc125s-pelsserA.pdf> the intuition is that it is a function of the richness of the path diversity. perhaps a tunable? randy