Evaluate and Compare Shared Symmetric-Key Methods

1. What is a substitution cipher? Provide an example.
2. What is a transposition cipher? Provide an example.
3. Decrypt the message “WKLVLVDWHVW” using a shift of three places.
4. Decrypt the message “HLEO LWROD” using a simple columnar transposition.
5. List two common vulnerabilities of symmetric-key ciphers.
6. What are two advantages of using symmetric-key methods for encryption?
7. What are key pairs in public key cryptography? How are they used?
8. What is the purpose of digital signatures in public key cryptography?
9. If the public key is [latex](e,n)=(5,14)[/latex] and the private key is [latex](d,n)=(11,14)[/latex], encrypt and then decrypt the message “[latex]3[/latex]” using RSA.
10. List two advantages of public key cryptography.
11. List two disadvantages of public key cryptography.
12. Compare the security of public key cryptography with symmetric-key methods.
13. Compare the speed of encryption and decryption in public key cryptography with symmetric-key methods.
14. Describe a real-world scenario where public key cryptography would be preferred over symmetric-key methods.
15. Describe a real-world scenario where symmetric-key methods would be preferred over public key cryptography.
16. KHow is key distribution handled in symmetric-key cryptography?
17. How is key distribution handled in public key cryptography?
18. What role do digital certificates play in public key cryptography?
19. Briefly discuss a current trend or future direction in the field of cryptography that interests you.