INTRODUCTION TO CRYPTOGRAPHY

What is Cryptographic Strength?

Relies on math, not secrecy Ciphers that have stood the test of time are public algorithms. Exclusive Or (XOR) is the "secret sauce" behind modern encryption. *All of the above.* Correct! All of these are critical.

What is the primary difference between Symmetric and Asymmetric encryption?

The same key is used to both encrypt and decrypt the message. Correct! That is what is symmetric about the process.

How many unique encryption keys are required for 2 people to exchange a series of messages using asymmetric public key cryptogrophy?

4 Correct! The sender and reciever both need a public key and a private key.

What is the correct sequence of steps required for Alice to send a message to Bob using asymmetric encryption?

Alice requests Bob's public key and uses it to encrypt her message. Alice then sends the encrypted message to Bob who decrypts it using his private key. Correct! Alice gets Bob's public key and uses it to encrypt the message that only Bob's secret private key can decrypt.

Which type of cryptographic attack is characterized by an attack based upon trial and error where many millions of keys may be attempted in order to break the encrypted message?

Brute force Correct! Modern computers can make billions of attempts per second, but good encryption could still make the process last billions of years.