Selecting a Randomness Extractor

In general, the choice of randomness extractor depends on the scenario in which it is to be used and, it is not always clear which extractor is best suited to a given scenario. In this section, we (informally) help solve this problem, based on the section ‘Overview of Extractor Library’ from Cryptomite’s accompanying paper (see [For2024]). We use the notation \(n_1, n_2\) to denote the length and \(k_1, k_2\) to denote the min-entropy of any first or second input string respectively. Additionally, \(m\) denotes the length of an output string, \(\epsilon\) the extractor error and \(O(.)\) denotes asymptotic quantities.

Note: there may be a small gain to be made by analysing the extractors individually if sufficiently motivated, but this flow-chart gives a good, general, approach to follow. The individual extractor parameters are given in the following table: