作者:CAITLYN KNIGHTS 2 年以前
204
Cryptography
Cryptography involves the practice of securing information by converting it into an unreadable format, known as ciphertext, which can only be transformed back into readable text, or plaintext, with the use of a key.
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Cryptography Important terms Key space Number of possible keys that can be created
from an algorithm Key Whats used to turn Plaintext->Ciphertext Description Ciphertext->Plaintext Encryption Plaintext->Ciphertext Cipher Encryption algorithm/technique Ciphertext Encrypted text Plaintext Readable text What is it Needs key to convert it back to readable texts Converts readable texts into a form which we cannot read Encryption Cipher Vigenenere Uses 26*26 a-z grid rot 13 Letter + 13 = letter Caesar Letter + 3= letter Authentication One's identity non-repudiation Sender did send the data Integrity Received data isn't tempted with or altered Confidentiality Can only be seen by intended people