Lesson 5 - Cryptographic Concepts

Question 1

What is the difference between stream and block ciphers?

Answer 1

A block cipher is padded to the correct size if there is not enough data in the plaintext. In a stream cipher, the plaintext is not divided into equal-size blocks.

Question 2

What are the key differences between symmetric and asymmetric cryptographic ciphers?

Answer 2

Symmetric encryption is used for confidentiality and uses the same key for encryption and decryption. Asymmetric is inefficient for encrypting or transporting large amounts of data.

Question 3

Applies an initialization vector to the first plaintext block to ensure that the key produces a unique ciphertext from any given plaintext.

Answer 3

Cipher Block Chaining

Question 4

Single hash function, symmetric cipher, or asymmetric cipher

Answer 4

Cryptographic Primitive

Question 5

What is salt?

Answer 5

Random or pseudo-random number or string using in conjunction with hashing password values.

(salt + password) * SHA = hash

Question 6

Which two cryptographic functions can be combined to authenticate a sender and prove the integrity of a message?

Answer 6

Public key cryptography and hashing