from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The set containing exactly every member of the domain of a function such that the member is mapped by the function onto an element of a given subset of the codomain of the function. Formally, of a subset B of the codomain Y under a function ƒ, the subset of the domain X defined by
Sorry, no etymologies found.
The functions are different from cryptographic hash functions, because they should be much faster and don't need to be resistant to preimage attack.
A preimage collision on MD5 (as requested in the article) is quite difficult.
Currently the strength of our standard digest algorithms (SHA-x) against preimage attacks is roughly that of the output length, and against collision attacks it's something less than half the output length (this is a topic of active research on SHA-1, which currently stands at