'Permuted choice' diaporamas de présentation

EE579T / CS525T Network Security 3: Symmetric Block Ciphers

754 views • 63 slides

Cryptography 2

Cryptography 2. Substitution Transposition. Secret Key Cryptosystem. Plaintext. Ciphertext. Plaintext. Encryption. Decryption. Sender. Recipient. K. C=E(K,M) M=D(K,C). K needs secure channel. Basic Encryption Techniques. Substitution (confusion) Permutation (diffusion)

649 views • 52 slides

Security

Security. Definition. Security: protecting the data (disclosure, alteration, destruction) against unauthorized users Aspects of security: Legal, social, ethical (use credit card?) Physical control (locked terminal room?) Policy questions (who is allowed to check what)

585 views • 40 slides