As we mentioned in class, a universal hash function is a function UH(K, M) that takes a key K, a message M and produces a fixed length digest. The universal hash is defined to be "secure" if for any two messages M₁ and M2, if K is selected uniformly at random, then the probability that UH(K, M₁) = UH(K, M₂) is approximately zero. == Suppose that H is a secure hash function. Is UH(K, M) = H(K||M) a secure universal hash function? Either prove the answer is "yes" using the security properties of H (which can be assumed), or show how the security of UH could be violated.

As we mentioned in class, a universal hash function is a function UH(K, M) that takes a key K, a message M and produces a fixed length digest. The universal hash is defined to be "secure" if for any two messages M₁ and M2, if K is selected uniformly at random, then the probability that UH(K, M₁) = UH(K, M₂) is approximately zero. == Suppose that H is a secure hash function. Is UH(K, M) = H(K||M) a secure universal hash function? Either prove the answer is "yes" using the security properties of H (which can be assumed), or show how the security of UH could be violated.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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