Chapter 1 (1-5): Introduction to MLSA Flashcards
the science of encryption
Cryptography
the science of breaking encryption
Cryptanalysis
combination of cryptography and cryptanalysis.
Cryptology
has been used in human communication for millennia as a way to preserve confidential information.
Cryptography
[7] Some Example of Cryptography
- Egyptian Nonstandard Hieroglyphs
- Spartans Scytale
- Caesar Cipher
- Vigenere Table
- Zimmerman Telegram
- Code Talker
- Enigma Machine
is a type of cryptography where every letter is replaced by a non-standard character.
Egyptian Nonstandard Hieroglyphs
is one of the simplest and most widely known encryptions. Each letter in the plaintext is replaces by a letter some fixed number of positions down the alphabet.
Caesar Cipher
a substitution type cypher that uses a table and a keywork in generating ciphertext.
Vigenere Table
was a secret diplomatic communication issued from the Germany Foreign Office.
Zimmerman Telegram
was a person employed by the military to use a little-known language as a mean o secret communication.
Code Talker
is a cipher device developed and user by Nazi Germany during World War II.
Enigma Machine
a mathematical algorithm that takes plain text and changes it into ciphertext for security purposes.
Modern Cryptography
is any cryptographic algorithm that is based on a shared key that is used to encrypt and decrypt.
Symmetric Cryptosystem
- The same method is used for encrypting and decrypting.
Symmetric Cryptosystem
this method uses two different methods in cryptographic process.
Asymmetric Cryptosystem
each plaintext digit is encrypted one at a time with corresponding digit of the keystream, to give a digit of the ciphertext stream.
Stream Cipher
The encryption is done character by character in a form of a stream.
Stream Cipher
is a deterministic algorithm operating on fixed-length groups of bits called blocks.
Block Cipher
The plaintext is divided into several block. Encryption is done block by block.
Block Cipher
is a method in cryptography by which cryptographic keys are exchanged between two parties, allowing use of cryptographic algorithm.
Key Exchange Protocol
[2] Cryptography Goals
- Encryption
- Authentication
prevent other from intercepting message.
Encryption
prevent someone from impersonating the receiver of the message.
Authentication
[4] Cryptographic Attacks
- Ciphertext Only
- Known Plaintext
- Chosen Plaintext
- Distinguishing Attack
attacker has only ciphertext.
Ciphertext Only
attacker has plaintext and corresponding ciphertext.
Known Plaintext
attacker can encrypt messages of his choosing.
Chosen Plaintext
an attacker can distinguish your cipher from an ideal cipher.
Distinguishing Attack
the security of an encryption system must depend only on the key, not on the secrecy of the algorithm.
Kerckhoffs’ Principle
is the computational task of finding representative of a residue class. It goes with the principle, easy to compute but hard to reverse.
Discrete Logarithm Problem
is an asymmetric key encryption algorithm got public-key cryptography which is based on Diffie-Hellman Key Exchange Protocol.
El Gamal Cryptosystem
described the El Gamal Cryptosystem.
Taher Elgamal (1985)
is a variant of El Gamal signature scheme, which should not be confused WITH Elg Gamal Encryption.
Digital Signature Algorithm (DSA)
was first published in Scientific American, August 1977. It is currently the “work horse” of internet security.
RSA Cryptosystem
