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Unformatted text preview: CIS 3362 Homework #3: Crack DES Assigned: 9/29/08 Due: 10/10/08 This is a group assignment for the whole class. The goal will be to determine the key used to encrypt a given plaintext and matching ciphertext. I will provide some basic (inefficient) Java code that carries out the encryption process for a block of code, given the plaintext and the key. To this, you will have to do the following: (1) Modify the code so that it just encrypts the given plaintext block with different keys, and automates the process of iterating through possible keys based on the restrictions that are provided below. Also, you should modify the code so that it checks to see if the ciphertext produced matches the given ciphertext. If so, you win the challenge and should note down the winning key (with parity bits)! (2) You may elect to streamline my code so it runs faster, so less computation time is necessary. Key Restrictions 24 bits of the key are restricted as follows (note: the convention being used is that the key...
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- Fall '08
- Information Security