QUESTION 10 How to encrypt a message with hashing? O Impossible. First concatenate a security key with some additional values, then XOR the results with the message O Hash the message, then rehash the result. Repeat multiple times. O First concatenate the message with a security key, then hash them together.

QUESTION 10 How to encrypt a message with hashing? O Impossible. First concatenate a security key with some additional values, then XOR the results with the message O Hash the message, then rehash the result. Repeat multiple times. O First concatenate the message with a security key, then hash them together.

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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Determine the security flaws that are present in each method of authentication, then provide a solution to the problem that is described below:Bob makes a hash of a password, and then he checks it against a database of previously hashed passwords.Bob runs a password via a hashing algorithm and then checks it against a database of passwords that have been hashed twice.
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