Take the 2-minute tour ×
Cryptography Stack Exchange is a question and answer site for software developers, mathematicians and others interested in cryptography. It's 100% free, no registration required.

Historically hashes have been from a large set (say 256 characters) to a smaller set (256 bits).

Also, hash functions that are P-complete have no known parallel algorithm; they must be computed serially which ensures a certain amount of temporal cost in computing them.

Three questions:

1)What is the technical term for hashes that map to a larger set than the domain?

2)Are there any good P-complete hashes?

3)Are there any good P-complete hashes that map to a larger set?

share|improve this question
1  
Encoding the string into a Game of Life grid and playing K rounds is an example of a P-complete hash. There must be a better one out there. –  Chad Brewbaker Dec 19 '12 at 17:43
    
Combining a hash with an iterated stream cipher should do the trick. –  CodesInChaos Dec 23 '12 at 23:10
    
add comment

migrated from security.stackexchange.com Dec 19 '12 at 18:00

This question came from our site for Information security professionals.

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.