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originates from a specific MIME content transfer encoding.

commonly used when there is a need to encode binary data that needs to be stored and transferred over media that are designed to deal with ASCII

converts the plain text in the format ASCII bytes

It is a special case of Caesar Cipher in which shift is always

an ancient trick where you just move every letter forward characters in the alphabet based on the key.

used during both the encryption and decryption processes

closely related to the disciplines of cryptology and cryptanalysis

means of altering data from a readable form to a protected form and back to the readable form.

a mathematical formula designed specifically to obscure the value and content of data.

the data that needs to be protected.

the mathematical algorithm that takes plaintext as the input and returns ciphertext

the encrypted, or unreadable, version of the plaintext.

the mathematical algorithm that takes ciphertext as the input and decodes it into plaintext

the value known to the sender that is used to compute the ciphertext for the given plaintext.

the value known to the receiver that is used to decode the given ciphertext into plaintext.

sometimes referred to as secret-key cryptography, uses the same key to encrypt and decrypt data.

one that uses the same key for
encryption and decryption.

Encrypt a group of bits as a single entity, inserting the plaintext to make it a block size multiple.

uses the same key to encrypt and decrypt a message, so both the sender and the receiver must know and use the same private key.

a method of encrypting text in which a cryptographic key and algorithm are applied to each binary digit in a data stream, one bit at a time.

employed for making uninformed cipher text

employed for increasing the redundancy ofthe plain text over the foremost a part of the cipher text to create it obscure.

method in which a message is transformed to conceal its real meaning.

encrypts a message by printing it in reverse order.

the process of translating plain text data into something that appears to be random and
meaningless

the process of converting ciphertext back to plaintext.

a structure or scheme consisting of a set of algorithms that converts plaintext to ciphertext to encode or decode messages securely.

create a fixed length of bits known as a block cipher with a secret key

use a pair of keys, a public key associated with the creator/sender for encrypting messages

Defined by machine administrators who set policy for one computer

Defined by enterprise administrators who set policy for enterprise domains

Lowest administrable policy level

Defined by the runtime host for setting load-time policy. Cannot be administered

a set of assumptions about how attackers might interact with a cipher and what they can and can’t do

is the operation that sends an input value to some function and gets the output in return, without exposing the details of that function.

takes a plaintext and returns a corresponding ciphertext, without revealing the secret key.

the attacker only sees what goes in and out of the cipher.

observe ciphertexts and do know the associated plaintexts.

observe ciphertexts but don’t know the associated plaintexts, and don’t know how the plaintexts were selected.

can perform encryption queries for plaintexts of their choice and observe the resulting ciphertexts.

more realistic than black-box models for applications.

a family of attacks within gray-box models.

a family of attacks on cipher implementations that are more powerful than side-channel attacks, and more expensive because they require sophisticated equipment

captures the intuition that ciphertexts shouldn’t leak any information about plaintexts as long as the key is secret.

an algorithm that returns random-looking bits given some secret value.

data is encrypted before being sent and decrypted after being received

Data is encrypted before being written to memory and decrypted before being read.

considered to be unconditionally secure, sometimes called strong, if it cannot be broken, even with infinite computational resources

considered computationally secure if it cannot be broken with available resources, either current or future

amount of data needed as input to the attack

The time needed to perform the attack. This is often called the work factor.

amount of memory needed to do the attack

encryption operation for which the plaintext input to be transformed is the ciphertext output of a previous encryption operation.

means the illegal effort of breaking into the back end of a system to get the username/password combination.

technique of trying every possible decryption key

a symmetric-key block cipher, known as the Data Encryption Algorithm (DEA) by ANSI and the DEA-1 by ISO

performed only once and happens before round 1

allows one bit to affect two substitutions, the dependency of the output bits on the input bits spreads

is used to provide Confusion, as it is dependent on the unknown key.
- It is a key-less fixed substitution cipherIt is a key-less fixed transposition cipher, but provides diffusion

It hides the relationship between the ciphertext and the key

It is a key-less fixed transposition cipher, but provides diffusion

Used prevalently on the web, it allows for secure messages to be sent between parties without having to agree on, or share, a secret key.

deals with authentication to match public keys to people with some level of security

It should be possible for the receiver of a message to ascertain its origin; an intruder should not be able to masquerade as someone else.

allow you to electronically sign documents using encryption.

sender should not be able to falsely deny later that the sender sent a message

occurs when a criminal hacker inserts themselves between a device and a server to intercept communications that can then be read and/or altered.

primarily used to encrypt the session key used for secret key encryption or the message's hash value

a symmetric block cipher chosen by the U.S. government to protect classified information.