AP CSP Cryptography Practice Questions

Using a Caesar Cipher with a shift of 4, encode the following message: COMPUTER SCIENCE

Using a Caesar Cipher with a shift of 7, encode: SECURITY

Decode these messages (figure out the shift value yourself): FSYNKNHFQNTY

• COMPUTERSCIENCE, Shift used: 4

• INFORMATIONTECH, Shift used: 2

• ENGINEERING, Shift used: 5

• MATHEMATICS, Shift used: 3

Using the keyword "PYTHON", encode the message. Use the study guide to refer to the Vigenère Table:

• SUDH KZKTPHN

• QWOP JYJQMGF

• TUVB LZLQRSN

• RTEG KYKTPHN

Using the keyword "CYBER", decode the message: VORVGG JDRZPMGL Show your work: CYBERC YBERCYB VORVGG JDRZPMGL Final decrypted message: __________________________

The following message was encrypted with a Vigenère cipher: FHVCLVS FWV BHK LRPMQXA You know the plaintext begins with the word "SECRETS". What is the keyword used for encryption?

• FORWARD

• BACKWARD

• ENCRYPT

• CIPHER

The following message was encrypted with a Vigenère cipher: FHVCLVS FWV BHK LRPMQXA You know the plaintext begins with the word "SECRETS". What is the full decrypted message?

• SECRETS ARE FUN TO UNLOCK

• SECRETS ARE HARD TO FIND

• SECRETS CAN BE DANGEROUS

• SECRETS ARE EASY TO GUESS

One key difference between symmetric and asymmetric encryption is:

• Symmetric encryption uses the same key for encryption and decryption, while asymmetric encryption uses different keys.

• Symmetric encryption is slower than asymmetric encryption.

• Asymmetric encryption does not use keys.

• Symmetric encryption is only used for digital signatures.

Why is the Vigenère cipher more secure than the Caesar cipher?

• Because it uses a longer key and polyalphabetic substitution.

• Because it uses only one alphabet for substitution.

• Because it is easier to break with frequency analysis.

• Because it does not use any key.

HTTPS uses encryption to protect your data when you visit websites by:

• Encoding data so only the intended recipient can read it

• Displaying a warning message

• Blocking all website access

• Slowing down your internet connection