Intro cryptography study questions

Nothing to hand in

This set of questions is intended to help guide your reading and video-watching as you learn about some cryptography basics.

Among other online resources, you might find Chapter 5 of Anderson's Security Engineering, 2e helpful. By the middle of the fourth week of class, make sure you can answer the following questions clearly and concisely.

• What's the difference between symmetric and asymmetric encryption algorithms? Be able to name at least two examples of each.
• Of what does an RSA public key consist? Same question for the private key. What's the required mathematical relationship between the two?
• Given an RSA public key, how do you encrypt a message? Given an RSA private key and a message encrypted with the corresponding public key, how do you obtain the original message?
• What's a public key infrastructure (PKI), and why would you want one?
• What is a cryptographic hash function, and what is one used for? What properties does it need to have? Be able to name at least two.
• What is a digital signature? How could Alice use RSA and a hash function to compute a signature? How could Bob verify Alice's signature?
• What is a message authentication code (MAC), and what is one used for? What properties does it need to have? Be able to name at least two.