Question

If Richard wants to send an encrypted message to Sue using a public key cryptosystem, which key does he use to encrypt the message?

A. Richard's public key
B. Richard's private key
C. Sue's private key
D. Sue's public key

Answer 1

To encrypt a message using a public key cryptosystem, Richard would use Sue's public key.

Step-by-step explanation:

If Richard wants to send an encrypted message to Sue using a public key cryptosystem, he would use Sue's public key to encrypt the message. In a public key cryptosystem, each user has a pair of keys: a public key and a private key. The public key is used for encryption, while the private key is used for decryption. Since Richard wants to send an encrypted message to Sue, he would need to use Sue's public key to encrypt the message, ensuring only Sue can decrypt it with her private key.