# Brute force searching, the typical set and Guesswork

arXiv: https://arxiv.org/abs/1301.6356 · HTML: https://mlsanity.com/paper/1301.6356/

## Key facts

- Cited by 1 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 27 Jan 2013.

## Built on by (most cited first, 1 of 1)

- [Syfer: Neural Obfuscation for Private Data Release](https://mlsanity.com/paper/2201.12406/) (2022)

## Abstract (arXiv)

Consider the situation where a word is chosen probabilistically from a finite list. If an attacker knows the list and can inquire about each word in turn, then selecting the word via the uniform distribution maximizes the attacker's difficulty, its Guesswork, in identifying the chosen word. It is tempting to use this property in cryptanalysis of computationally secure ciphers by assuming coded words are drawn from a source's typical set and so, for all intents and purposes, uniformly distributed within it. By applying recent results on Guesswork, for i.i.d. sources it is this equipartition ansatz that we investigate here. In particular, we demonstrate that the expected Guesswork for a source conditioned to create words in the typical set grows, with word length, at a lower exponential rate than that of the uniform approximation, suggesting use of the approximation is ill-advised.