Question

Explain what the following notions mean for hash functions and compare their strength. Please don’t copy the definitions from the class slides, explain them with your own words.

• Collision Resistant

• Pre-image Resistant

• Second Pre-image Resistant

Answer 1

ANSWER :-

hash work competition was an open challenge held by the US National Institute of Standards and Technology (NIST) to build up a new hash function called SHA-3 to supplement the older SHA-1 and SHA-2. The challenge was formally reported in the Federal Registeron November 2,2007

collision resistance

collision resistance is a property of cryptographic hash works: a hash work H is impact safe on the off chance that it is elusive two information sources that hash to a similar yield; that is, two data sources

Pre-image Resistant :

pre-image opposition: for basically all pre-indicated yields, it is computationally infeasible to discover any info that hashes to that yield,

i.e., given y, it is hard to discover a x with the end goal that h(x) = y

To improve protection from crash assaults, twofold hashing is a decent solution[citation needed] in the event that somebody finds a pre-picture assault on the main hash. The Bitcoin framework utilizes twofold hashed that was a typical method to back off hashing looks in the 2000's

Second Pre-image Resistant:

it is computationally infeasible to find any second input which has the same output as that of a specified input, i.e., given x, it is difficult to find a second pre-image x′ ≠ x such that h(x) = h(x′)

Crash opposition infers second-pre-picture obstruction, however does not ensure pre-picture obstruction. Then again, a second-pre-picture assault infers an impact assault (inconsequentially, since, notwithstanding x′, x is as of now known ideal from the begin).

Thus,we explained in our own words

Thank you