ISAAC (cipher) Guide, Meaning , Facts, Information and Description
ISAAC is a pseudorandom number generator designed by Bob Jenkins (1996) to be cryptographically secure. The name is an acronym for Indirection, Shift, Accumulate, Add, and Count.
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2 Cryptanalysis 3 References 4 External links |
Operation
The ISAAC algorithm seems to be inspired by RC4. It uses an array of 256 4-byte integers (called mm) as the internal state, writing the results to another 256-integer array, from which they are read one at a time until empty, at which point they are recomputed. The computation consists of altering mm[i] with mm[i^128], two elements of mm found by indirection, an accumulator, and a counter, for all values of i from 0 to 255. Since it only take about 19 32-bit operations for each 32-bit output word, it is extremely fast on 32-bit computers.
This is an Article on ISAAC (cipher). Page Contains Information, Facts Details or Explanation Guide About ISAAC (cipher) Cryptanalysis
Cryptanalysis has been undertaken by Marina Pudovkina (2001). Her attack can recover the initial state with a complexity that is
approximated to be less than the time needed for searching through the square root of all possible initial states. In practice this means that the attack needs instead of . This has yet no impact on the practical security of ISAAC.References
External links