Key Exchange

What is the primary logistical challenge in key exchange?

• Ensuring the key is known by only one party.

• Physically transferring the key across a secure medium.

• Sharing an encryption key across an insecure medium without physical transfer.

• Encrypting small amounts of data across the internet.

Which method is NOT an example of out-of-band key exchange?

• Telephone

• Courier

• In-person exchange

• Network transfer

How can an in-band key exchange be secured when sending a symmetric key over a network?

• By using a physical courier service.

• By exchanging the key in person.

• By protecting the key with additional encryption, such as asymmetric encryption.

• By sending the key via telephone.

What is a characteristic of session keys?

• They are permanent and rarely changed.

• They are used for long-term data storage.

• They are ephemeral and need to be changed often.

• They are always generated by the server.

How do two devices create the same symmetric key using public and private key cryptography without sending the symmetric key across the network?

• By combining each device's private key with the other device's public key.

• By encrypting the symmetric key with a shared secret.

• By physically exchanging the symmetric key.

• By using a third-party key distribution center.