Very Nice. Thanks :) Wk #10 HW 1. Define and describe cryptography. Cryptography is the practice of encoding data so that it can only be decoded by a specific intended person. It is the way data is secured when it is sent over a network from one computer to another to protect it from theft, alteration and also for user authentication. 2. Define and describe symmetric and asymmetric cryptography.-Symmetric cryptography is where there is a shared encryption/decryption key. The sender uses a key and an encryption algorithm to encrypt the data, and the receiver uses the same key with a matching decryption algorithm to decode the data. There is a shared secret key between sender and receiver. In symmetric cryptography, a substitution cipher is a method of encryption by which one symbol of plaintext are substituted with another. In a transposition cipher, units of the plaintext are rearranged in a different and usually quite complex order, but the units themselves are left unchanged. Block ciphers convert a fixed-length block of plain text into cipher text of the same length. One commonly used
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This note was uploaded on 01/19/2012 for the course COMPUTER S 100 taught by Professor Brown during the Spring '11 term at Strayer.