'Shift cipher' diaporamas de présentation

Cryptography

Cryptography. Chapter 5. Objectives. Identify and describe the three types of cryptography. List and describe current cryptographic algorithms. Explain how cryptography is applied for security. Agenda. Basic Terms and the Encryption/Decryption Process Types of Ciphers

1.09k views • 73 slides

Classical Ciphers

Terminology Monoalphabetic ciphers (Shift, Affine) Permutation Cipher; Vigenere Substitution Cipher and one-time pad. Classical Ciphers. CSCI283/172 Fall 2006 GWU. From Schneier. Some terminology.

466 views • 46 slides

Classical Ciphers

Terminology Monoalphabetic ciphers (Shift, Affine) Permutation Cipher; Vigenere Substitution Cipher and one-time pad. Classical Ciphers. CSCI283 Fall 2005 Lecture 5 Part 1 GWU. From Schneier. Some terminology.

517 views • 46 slides

Cryptography

404 views • 40 slides

Classical Ciphers

Classical Ciphers. CSCI 284/162 Spring 2009 GWU. Formal definition: cryptosystem. A cryptosystem consists of: P set of all plaintext C set of all ciphertext K set of all keys E set of encryption rules, e K : P ? C D set of decryption rules d K : C ? P d K e K (x) = x

545 views • 39 slides

Classical Ciphers

Classical Ciphers. CSCI 284/162 Spring 2008 GWU. Formal definition: cryptosystem. A cryptosystem consists of: P set of all plaintext C set of all ciphertext K set of all keys E set of encryption rules, e K : P ? C D set of decryption rules d K : C ? P d K e K (x) = x

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Cryptography

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CS363

Week 1 - Friday. CS363. Last time. What did we talk about last time? Computer criminals Methods of defense Cryptography basics. Questions?. Project 1. Security tidbit of the day.

572 views • 36 slides

CS363

Week 1 - Friday. CS363. Last time. What did we talk about last time? Computer criminals Methods of defense Cryptography basics. Questions?. Project 1. Security tidbit of the day.

460 views • 36 slides

Classical Ciphers

Classical Ciphers. CSCI 284/162 Spring 2007 GWU. Formal definition: cryptosystem. A cryptosystem consists of: P set of all plaintext C set of all ciphertext K set of all keys E set of encryption rules, e K : P ? C D set of decryption rules d K : C ? P d K e K (x) = x

466 views • 34 slides

DPEFT, DJQIFST boe TFDSFU XSJUJOH.

DPEFT, DJQIFST boe TFDSFU XSJUJOH. If for each letter, you instead write the letter before it in the alphabet, you will discover what we are doing this morning. DPEFT, DJQIFST boe TFDSFU XSJUJOH. becomes CODES, CIPHERS and SECRET WRITING. WHY?. Codes have been important throughout history.

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Information Security CS 526 Topic 2

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Information Security CS 526 Topic 2

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Announcements: Assignment 1 due tomorrow in class. Questions? Roll Call Today: Vigenere ciphers

DTTF/NB479: Dszquphsbqiz Day 5. Announcements: Assignment 1 due tomorrow in class. Questions? Roll Call Today: Vigenere ciphers Pronunciation?. Vigenere Ciphers. Idea: the key is a vector of shifts Ex. Use a word like hidden (7 8 3 3 4 13) . Example:

298 views • 17 slides

Announcements: Assignment 1 due tomorrow in class. Questions? Roll Call Today: Vigenere ciphers

DTTF/NB479: Dszquphsbqiz Day 5. Announcements: Assignment 1 due tomorrow in class. Questions? Roll Call Today: Vigenere ciphers Pronunciation?. Vigenere Ciphers. Idea: the key is a vector of shifts Ex. Use a word like hidden (7 8 3 3 4 13) . Example:

174 views • 17 slides

Welcome to Cryptology

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CRYPTOGRAPHY

359 views • 13 slides