Active Domain Expansion for Narrow-pipe Hash
نویسنده
چکیده
In this article, we give an approach to the problem of entropy and codomain reducing in a normal iterative hash function. The problem relies on the case of effective domain reducing which causes the empty set of a approximative probability e−1 in a iteration. We will keep, hold or recover the entropies by a way of Active Domain Expansion(ADE). ADE replaces the input message block by ∑ Mi in a normal iterative hash function. A sum block ∑ Mi is a sum of the foregoing i ”Encoded Blocks”. ADE makes the Sum Block ∑ Mi a big domain to satisfy a surjection function, it can recover the entropy and codomain.We put emphasis on succinct narrow-pipe hash in this paper and a normal narrow-pipe hash function can resist this reducing. keywords: domain expansion, entropy, narrow -pipe hash , surjection
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Active Domain Expansion for Normal Narrow-pipe Hash Functions
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