SCMT 455- CH 8

transposition cipher

A cryptographic operation that involves simply rearranging the values within a block based on an established pattern. Also known as a permutation cipher.

Exclusive OR (XOR)

A function within boolean algebra used as an encryption function in which two bits are compared. If the two bits are identical, the result is a binary 0. If the two bits are not identical, the result is a binary 1

Link Encryption

A series of encryptions and decryptions between a number of systems, wherein each system in a network decrypts the message sent to it and then re-encrypts it using different keys and sends it to the next neighbor, and this process continues until the message reaches the final destination

keyspace

The entire range of values that can be used to construct an individual key

Plaintext or cleartext

The original unencrypted message, or a message that as been successfully decrypted.

Steganography

The process of hiding messages within the digital encoding of a picture or graphic so its almost impossible to detect that the hidden message even exists

polyalphabetic substitution

a substitution cipher that incorporates two or more alphabets in the encryption process

Monoalphabetic substitution

a substitution cipher that only incorporates a single alphabet in the encryption process

Vigenere Cipher

advanced type of substitution cipher that uses a simple poly-alphabetic code (made up of 26 distinct cipher alphabets)

Bit stream cipher

an encryption method that involves converting plaintext to ciphertext one bit at a time

Block Cipher

an encryption method that involves dividing the plaintext into blocks or sets of bits and then converting the plaintext to ciphertext one block at a time

Bluetooth

can be exploited by anyone within approximately 30 foot range, unless suitable security controls are implemented

book cipher

ciphertext consists of a list of codes representing page, line, and word numbers of plaintext word

WiFi Protected Access (wpa and wpa2)

created to resolve issues with WEP

Wired Equivalent Privacy (WEP)

early attempt to provide security with the 8002.11 network protocol. It is now considered too cryptographically weak to provide any meaningful protection from eavesdropping

asymmetric encryption

incorporates mathematical operations involving both a public key and a private key to encipher or decipher a message. Either key can be used to encrypt a message but then the other key is required to decrypt it

hash functions

mathematical algorithms that generate a message summary or digest to confirm message identity and integrity

Symmetric encryption

method in which the same algorithm and secret key are used both to encipher and decipher the message; also known as private- key encryption

Next generation Wireless Protocols

protocol for establishing secure communications over an 802.11 wireless network

Ciphertext or Cryptogram

scrambled version of a plaintext that results from applying the encryption algorithm and the encryption key

Cryptanalysis

study of breaking the codes and ciphers

cryptology

study of making the codes and ciphers

Work Factor

the amount of effort required to perform cryptanalysis on an encoded message

cryptography

the enciphering and deciphering of messages in secret code or cipher

Key (cryptovariable)

the information used in conjunction with the algorithm to create the ciphertext from the plaintext; it can be a series of bits used in a mathematical algorithm or the knowledge of how to manipulate the plaintext

Algorithm

the mathematical formula or method used to convert an unencrypted message into an encrypted message. This sometimes refers to the programs that enable the cryptographic processes

decryption

the process of converting an encoded or enciphered message (ciphertext) back to its original readable form (plaintext). Also referred to as deciphering

encryption

the process of converting an original message into a form that cannot be used by unauthorized individuals also known as encipher

code

the process of converting components (words or phrases) of an unencrypted message into encrypted components

Cipher or cryptosystem

the transformation of the individual components of an unencrypted message into encrypted components or vice versa