7.1 Cryptography
Encryption key
A string of bits randomly generated using a specific cipher. An encryption key is used to encrypt or decrypt data.
What are uses of blockchain in addition to cryptocurrency?
Contracts, records, or other types of information.
What is a legitimate use for steganography?
For watermarking images.
Which algorithms can be used to generate a hash?
Mathematical algorithms like MD5 and SHA.
Above all else, what must be protected to maintain the security and benefit of an asymmetric cryptographic solution, especially if it is widely used for digital certificates? - Public keys - Private keys - Cryptographic algorithm - Hash values
Private keys
What does a digital signature provide?
Provide non-repudiation, which means the sender cannot deny having sent the message.
Which of the following can be classified as a stream cipher? - Blowfish - Twofish - AES - RC4
RC4
Mary wants to send a message to Sam in such a way that only Sam can read it. Which key should be used to encrypt the message? - Sam's private key - Mary's private key - Sam's public key - Mary's public key
Sam's public key
A receiver wants to verify the integrity of a message received from a sender. A hashing value is contained within the digital signature of the sender. Which of the following must the receiver use to access the hashing value and verify the integrity of the transmission? - Receiver's public key - Receiver's private key - Sender's private key - Sender's public key
Sender's public key
When a cryptographic system is used to protect data confidentiality, what actually takes place? - Encrypted data transmission is prohibited. - Data is available for access whenever authorized users need it. - Unauthorized users are prevented from viewing or accessing the resource. - Data is protected from corruption or change.
Unauthorized users are prevented from viewing or accessing the resource.
Which of the following algorithms are used in symmetric encryption? (Select two.) - 3DES - RSA - Blowfish - Diffie-Hellman -ECC
- 3DES - Blowfish
Which of the following algorithms are used in asymmetric encryption? (Select two.) - AES - Diffie-Hellman - Twofish - RSA - Blowfish
- Diffie-Hellman - RSA
Blockchain
A decentralized and distributed ledger of transactions between two or more parties. Blockchain uses cryptography to keep sensitive data secure.
What is the difference between symmetric and asymmetric encryption?
Asymmetric encryption uses two keys instead of one. Symmetric encryption uses the same key to encrypt and decrypt data.
Which of the following encryption mechanisms offers the least security because of weak keys? - AES - DES - IDEA - TwoFish
DES
What type of attack uses a large list of common words and phrases?
Dictionary attack
Which type of password attack employs a list of pre-defined passwords that it tries against a login prompt? - Dictionary attack - Collision attack - Birthday attack - Downgrade attack
Dictionary attack
Which term means a cryptography mechanism that hides secret communications within various forms of data? - Ciphertext - Algorithm - Cryptanalysis - Steganography
Steganography
Ciphertext
The encrypted form of a message that is readable only by those for whom the message is intended.
Steganography
The practice of concealing a file, message, image, or video within another file, message, image, or video.
Decryption
The process of converting data from ciphertext into plaintext.
Encryption
The process of using an algorithm or cipher to transform data from cleartext to ciphertext in order to protect the confidentiality, integrity, and authenticity of the message.
Cipher/algorithm
The process or formula used to encrypt a message or otherwise hide the message's meaning.
Plaintext
The readable form of a message.
Cryptography
The science and study of concealing information.
