CIS 481 - Chapter 8
Registration authority
a third party that operates under the trusted collaboration of the certificate authority and handles day-to-day certification functions
Hash functions
algorithms that generate a message summary to confirm message identity and integrity
Symmetric encryption
cryptographic method in which the same algorithm and secret key are used to encipher/decipher the message
Asymmetric encryption
cryptographic method that incorporates mathematical operations involving both a public key and a private key to encipher and decipher the message
Transposition cipher
cryptographic operation that involves rearranging the values within a block based on an established pattern
Digital signatures
encrypted message components that can be mathematically proven as authentic
Substitution cipher
encryption method in which one value is substituted for another
Bit stream cipher
encryption method that involves converting plaintext to ciphertext one bit at a time
Keyspace
entire range of values that can be used to construct an individual key
Cryptology
field of science that encompasses cryptography and cryptanalysis
Exclusive OR operation
function within Boolean algebra used as an encryption function in which 2 bits are compared
Hash algorithm
functions that create a hash value by converting variable-length messages into a single fixed-length value
Diffie-Hellman key exchange
hybrid cryptosystem that facilitates exchanging private keys using public-key encryption
Certificate authority
in PKI, a third party that manages users' digital certificates
Public key infrastructure
integrated system of software, encryption methodologies, protocols, legal agreements, and third party services that enables users to communicate securely through the use of digital certificates
Secret key
key that can be used in symmetric encryption both to decipher and encipher the message
Message authentication code
key-dependent, one-way hash function that allows only specific recipients to access the message digest
Session keys
limited-use symmetric keys for temporary communications during an online session
Steganography
process of hiding messages
Cryptography
process of making and using codes to secure information
Cryptanalysis
process of obtaining the plaintext message from a ciphertext message without knowing the keys
Nonrepudiation
process of verifying that a message was sent by the sender and thus cannot be refuted
Digital certificates
public-key container files that allow PKI system components and end users to validate a public key and identify its owner
Polyalphabetic substitution
substitution cipher that incorporates two or more alphabets in the encryption process
Monoalphabetic substitution
substitution cipher that only incorporates a single alphabet in the encryption process
Vernam cipher
this cipher uses a set of characters for encryption operations only one time and then discards it
Cipher
transformation of the individual components of an unencrypted message into encrypted components
Ciphertext
unintelligible encrypted message resulting from an encryption
Message digest
value representing the application of a hash algorithm on a message that is transmitted with the message so it can be compared with the recipient's locally calculated hash of the same message