D334 Intro To Cryptography (Professor Wolf's Playlist)

D334 Intro To Cryptography (Professor Wolf's Playlist) Leave the first rating Students also studied Terms in this set (157) Science Computer Science Computer Security and Reliability Save Introduction to Cryptography - D33...120 terms PerkoniPreview WGU - Intro to Cryptography - D33...35 terms jtally8Preview WGU D344 - Cryptosystems 31 terms LeiptrPreview

E-CES,

20 terms sofa Practice questions for this set Learn1 / 7Study using Learn Encrypt data in fixed-sized blocks Bifid CipherA 5x5 matrice grid that matches letters into numeric values.PlayfairA 5x5 grid created with a secret phrase (letters cannot repeat in the grid.Homophonic Substitution CipherA substitution Cipher that replaces plaintext with multiple possible cipher texts.Monoalphabetic Cipher/Caesar CodingCreated by Julius Caesar (uses 3 letter shift) Choose an answer 1Stream Encryption2Block Encryption 3Port Encryption4Record Encryption Don't know?

Scrambled AlphabetEach letter in the alphabet is mapped to a random letter.Vigenère CipherKnown as a polyalphabetic cipher and uses a number of cipher alphabets. Popular method is to use an agreed upon word code.Morse CodePulses of electronic currents along the wires with silence in-between them.Translates characters into dots (.) and dashes (-).Fractionated Morse CipherExtra layer of encryption to the traditional morse cipher.Uses 26 character key mapping and converts plain text into Morse Code.Pig PenUses a mono-alphabetic substitution method.Four grid in a square and a diagonal shape.Rail CodeScrambled the plaintext letters in some way, where it is not possible for the human eye to spot a pattern.Scramble method is known as the Rail Fence Cipher. Message is written in a sequence across a number of rails.CombinationsRepresent selections of items from a larger set without regard to the order in which they are chosen.PermutationsAn arrangement of objects in a specific order.One-Time Pad (OTP)A Cipher code that is only used once.DataComputers read this in binary 1's and 0's.ASCII (American Standard Code for Information Interchange) 8-bit binary code set with 256 characters UTF-16Extends characters to 16 bit values giving 65,536 values HexadecimalSplits the bit stream into groups of four bits.Values 0 to 15 CRC (Cyclic Redundancy Check)Detects errors in the binary digits.Reed-SolomonA more complex data integrity scheme to not only detect errors but correct them as well.Huffman CodingCompresses data by looking for patterns within binary data or within metadata.Lemple-Ziv-Welch (LZW)Adaptive dictionary data compression technique known as LZ-77.

Little EndianLeast significant byte stored first Big EndianMost significant byte stored first IntegersCan be positive or negative and no fractional part Rational NumbersFractions such as 3/4 Real NumbersAre both integers and rational numbers such as 2.3 Prime numbersRepresent integers and can only be divisible by 1 and itself.Example is number 3.Natural numbersRepresent positive numbers such as (1, 5, 16) How to XOR1 + 0 = 1

1 + 1 = 0

How to OR1 + 1 = 1

1 + 0 = 1

How to AND1 + 0 = 0

1 + 1 = 1

Mod OperatorAfter you divide, the answer is the remainder.

Example: 17 mod 5 -> 17/5 = 3, so the remainder is 2

Pseudo-Random Number Generator (PRNG)Repeats random numbers after a given time (periodic).True Random Number Generator (TRNG)Generates a true random number

Asymmetric EncryptionUses two keys: Public and Private

Public KeyEncrypts data Private KeyDecrypts data Symmetric Encryption/Shared Secret KeyUses one key to encrypt and decrypt Frequency AnalysisAnalyzes cipher text to identify text variation and comparing it to the standard english characters

Electronic Code Book (ECB)- Most basic, weak, and unsecure mode.

• Each block processed separately
• No Salt or IV is used
• Same key will be used to encrypt each block

Cipher Block Chaining (CBC)-Minor step up from ECB with the incorporation of an initialization vector for the first block.-Results of encryption from previous block is input into to encryption process of the current block.Cipher Feedback (CFB)-Converts the block cipher into a self-synchronizing stream cipher.-Current block takes output of the XOR ⊕ process vs from the cipher stage of the previous block (difference between CFB and OFB).Output Feedback (OFB)-Converts the block cipher to a synchronous stream output.-Current block takes output from the cipher stage vs from the output of the XOR process of the previous block (difference between CFB and OFB).Cipher Modes - CTR- Converts the block cipher into a stream cipher.

• Generates a counter value and a nonce, and encrypts this, in order to EX-OR

with the plain text block.Pretty Good Privacy (PGP)allows users to send encrypted and authenticated emails Stream EncryptionData stream where one bit at a time is encrypted.Faster then block encryption and used for real-time applications Block EncryptionEncrypt data in fixed-sized blocks Block Encryption AlgorithmsCamellia 3Des 2Twofish Blowfish

RC2, 5, 6

AES IDEA DES XTEA SkipJack

Memory Technique: C32BRAIDSXS