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Note ID collisions: Unlikely but not impossible

Jeffrey Benjamin Brown edited this page Jul 28, 2017 · 2 revisions

Collision: What it means

Notes in Semantic Synchrony have associated IDs. When a note is created, it is assigned a new ID at random. It is therefore possible for two note IDs to "collide". If that ever happened, one of them would be annihilated.

Why collision is unlikely

Each ID is 16 characters long, and can be any letter (upper or lower case) or any digit. Thus there are 62^16 possible ID values.

Perhaps because it is relevant to cryptography we have a formula for n(p;H), the minimum number n of random selections one would have to make from H things in order for the probability that two selections coincide to be p or greater.

Setting H = 62^16 and p = 0.01% = 0.0001, we obtain:

n = sqrt (2 * (62^16) * (log ( 1 / (1 - 0.0001) ) ) )
  = 3,087,872,584,346.358

That is, a graph would have to have more than 3 trillion notes before there was a .01% probability that any pair of notes had collided.

Currently Semantic Synchrony has 3 known users. Before we get anywhere close to that 3 trillion note threshold, we promise, we'll make the addresses longer.