18.3.1. Folklore Belief and Key Exchange Protocol

Try these first

1. 1.

   What is symmetric key encryption?

   Hint

   Think about the one key function.

2. 2.

   What does the Diffie-Hellman protocol achieve?

   Hint

   Remember the myth it disproved.

3. 3.

   What is the main purpose of symmetric key encryption?

   • To hide the algorithm used
   • To securely share a common key
   • To encrypt messages using one key for both processes

   Hint

   Think about the one key function.

4. 4.

   True or False: The Diffie-Hellman key exchange allows for easy extraction of the shared key by an eavesdropper.

   • True
   • False

   Hint

   Consider how easy it is to compute the key.

5. 5.

   Given the base of a cyclic group and a prime number, describe how Sita and Ram can independently create their keys without revealing them.

   Hint

   Think about the steps they need to take before sharing.

6. 6.

   Discuss how the discrete logarithm's difficulty ensures the security of the Diffie-Hellman protocol.

   Hint

   Recall how this protects their secret.