CrashCourse Computer Science: Cryptography Quiz

What is the primary goal of the 'defense in depth' strategy in computer security?

• To use multiple layers of security mechanisms

• To create a single strong barrier against attacks

• To rely solely on encryption for security

• To eliminate all bugs in the system

What does the term 'cryptography' roughly translate to?

• Encrypted text

• Hidden messages

• Public writing

• Secret writing

What is the process of converting plain text into ciphertext called?

• Permutation

• Decryption

• Encryption

• Substitution

Which historical figure is known for using the Caesar cipher?

• Queen Elizabeth

• Mary, Queen of Scots

• Julius Caesar

• Alan Turing

What is a major drawback of basic substitution ciphers?

• They are too complex to use

• They preserve letter frequencies

• They require a large key

• They are not reversible

What type of cipher is a columnar transposition cipher?

• Caesar cipher

• Permutation cipher

• Substitution cipher

• Reflector cipher

What was the primary use of the Enigma machine during World War II?

• To store secret documents

• To send encrypted messages

• To generate random numbers

• To decode enemy messages

What was a fatal cryptographic weakness of the Enigma machine?

• It used only one rotor

• It could encrypt a letter as itself

• It had no plugboard

• It was too slow

What was the key length of the original Data Encryption Standard (DES)?

• 256 bits

• 128 bits

• 192 bits

• 56 bits

What is the primary advantage of the Advanced Encryption Standard (AES) over DES?

• It uses smaller keys

• It is easier to implement

• It is less secure

• It uses much bigger keys