Cryptography Overview

Flashcards covering key concepts in cryptography, including definitions, encryption types, and important algorithms.

Cryptography

The science of protecting information by transforming it into a form that is unreadable to unauthorized users.

Plaintext

The original message before encryption.

Ciphertext

The coded message resulting from the encryption process.

Encryption

The process of converting plaintext into ciphertext.

Decryption

The process of restoring the plaintext from the ciphertext.

Symmetric Encryption

A type of encryption where the same key is used for both encryption and decryption.

Asymmetric Encryption

A type of encryption that uses different keys for encryption (public key) and decryption (private key).

Hash Function

A function that converts input data into a fixed-length string (hash value), ensuring integrity.

Digital Signature

An encrypted hash value that verifies the integrity and authenticity of a message using a user's private key.

Caesar Cipher

A substitution cipher that shifts letters of the alphabet by a fixed number.

Cryptanalysis

Techniques used for deciphering a message without knowledge of the enciphering details.

Stream Cipher

A cipher that encrypts data one bit or byte at a time.

Block Cipher

A cipher that encrypts data in fixed-size blocks (commonly 64 or 128 bits).

Key

A piece of information that determines the output of a cryptographic algorithm.

Encryption/Decryption Algorithms

Procedures used to encrypt or decrypt messages, such as AES and RSA.

Integrity

The assurance that information is accurate and unaltered.

Confidentiality

The principle of keeping information secret from unauthorized access.

Authentication

The process of verifying the identity of a person or system.

Non-repudiation

A service that ensures a party cannot deny the authenticity of their signature on a document or a message.

Cipher

A method or algorithm for encrypting and decrypting messages.

Substitution

Encryption technique where each letter in the plaintext is replaced by a different letter or symbol.

Permutation

Encryption technique where the order of elements in the plaintext is rearranged.