Using universal hashing (in a randomized algorithm or data structure) refers to selecting a hash function at random from a family of hash functions with a certain mathematical property (see definition below). This guarantees a low number of collisions in expectation, even if the data is chosen by an adversary. Many universal families are known (for hashing integers, vectors, strings), and their evaluation is often very efficient. Universal hashing has numerous uses in computer science, for example in implementations of hash tables, randomized algorithms, and cryptography.
Read more about Universal Hashing: Introduction, Mathematical Guarantees, Constructions
Famous quotes containing the word universal:
“The earliest instinct of the child, and the ripest experience of age, unite in affirming simplicity to be the truest and profoundest part for man. Likewise this simplicity is so universal and all-containing as a rule for human life, that the subtlest bad man, and the purest good man, as well as the profoundest wise man, do all alike present it on that side which they socially turn to the inquisitive and unscrupulous world.”
—Herman Melville (1819–1891)