3.3: Cryptography Flashcards
Encryption
The process of transforming plaintext into ciphertext.
plaintext
Encryption is the act of hiding information in plain sight. read by anyone who has access to it.
Ciphertext
A message, file, or stream of data that has been transformed by an encryption algorithm and rendered unreadable.
Hash function
A cryptographic operation on a block of data that returns a fixed-length string of characters, used to verify the integrity of a message.
Message Digest
The output of a cryptographic function
Digital signature
The result of encrypting the hash of a message with the originator’s private encryption key, used to prove the authenticity and integrity of a message.
Algorithm
A specific mathematical formula that is used to perform encryption, decryption, message digests, and digital signatures.
Decryption
The process of transforming ciphertext into plaintext so that a recipient can read it.
Cryptanalysis
An attack on a cryptosystem where the attacker is attempting to determine the encryption key that is used to encrypt messages.
Encryption key
A block of characters, used in combination with an encryption algorithm, used to encrypt or decrypt a stream or blocks of data. An encryption key is also used to create and verify a digital signature.
Key encrypting key
An encryption key that is used to encrypt another encryption key.
Block cipher
An encryption algorithm that operates on blocks of data.
Stream cipher
A type of encryption algorithm that operates on a continuous stream of data such as a video or audio feed.
• Initialization vector (IV)
A random number that is needed by some encryption algorithms to begin the encryption process.
• Symmetric encryption
Symmetric encryption refers to those methods where the same key is used to encrypt and decrypt the plaintext.
• Asymmetric encryption , or public key cryptography A .
A method for encryption, decryption, and digital signatures that uses pairs of encryption keys, consisting of a public key and a private key .
• Key exchange
A technique that is used by two parties to establish a symmetric encryption key when there is no secure channel available.
• Nonrepudiation
The property of digital signatures and encryption that can make it difficult or impossible for a party to later deny having sent a digitally signed message, unless they admit to having lost control of their private encryption key.
