ITEC111

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

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

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

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

observe ciphertexts and do know the associated plaintexts.

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

the attacker has access to a cipher’s implementation.

more realistic than black-box
models for applications.

a source of information that depends on the implementa-tion of the cipher, be it in software or hardware.

more expensive because they require sophisticated equipment

it cannot be broken, even with infinite computational resources.

it cannot be broken with available resources, either current or future.

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

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 method of protecting information and communications through the use of codes, so that only those for whom the information is intended can read and process it.

refers to secure information and communication techniques

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

the process of converting ciphertext back to plaintext

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

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

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 and a private key that only the originator
knows

one that uses the same key for
encryption and decryption.

defined by machine administrators who set policy for one computer
Can set policy that excludes modification from the user level but
not from the enterprise level

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

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

refers to the abbreviated form Rotate by 13 places.

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

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

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

It hides the relationship between the ciphertext and the key

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

It hides the relationship between the ciphertext and the plaintext

how many rounds does the des will perform

how many times does the initial permutation happens and where does it perform

how does the shifting in des happens every round

this allows one bit to affect 2 substitution, the dependency of the outputs on the input bits spread

in expansion permutation what would we need to do in order to proceed to sbox permutation

in order to perform sbox what do we need to do

how many times does the inverse permutation happens and where does it perform

it makes 32 bits rpt of ip expand to 48 bits

in des, what would happen if we disregard every 8 bit in our key

what is the bit key of des

what field is intricately to the studies of cryptology and cryptanalysis

the term used to describe the scientific study focused on examining and disrupting secure forms of communication

a collection of presumptions about an attackers potential interactions with a cipher, outlining their capabilities and limitations

every 8 bit of the original 64th bit key is used for parity resulting into

describes a situation where a single bit influences two substitutions, causing the impact of input bits to extend to output bits

this is used to provide confusion, as it is dependent on the unknown key

what model does the attacker can solely observe the inputs and outputs of the cipher

it is a key-less fixed trasposition cipher, but provides diffusion

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

identifies the type of attack that stems from information acquired through physical implementation

an algorithm is considered as unconditionally secure if it cannot be broken with available resources, either current or future

what makes the otp cipher breakable is because of uts key randomness...