# Question 397 of 530 from exam 400-251: CCIE Security written exam

### Question

Which three statements about the RSA algorithm are true to provide data confidentiality? (Choose three.)

### Answers

### Explanations

CDF.

RSA algorithm is one of the most popular public-key encryption methods used to provide data confidentiality. The algorithm is based on the mathematical principles of factoring large numbers, and it uses two keys, a public key and a private key, to encrypt and decrypt data. Here are the explanations of the three true statements about the RSA algorithm for data confidentiality:

C. The RSA algorithm creates a pair of public-private keys and the public key is shared to perform encryption. When data needs to be encrypted, the sender uses the recipient's public key to encrypt the data, and only the corresponding private key can decrypt it. This process ensures that only the intended recipient can decrypt and access the data.

D. The private key is never shared after it is generated. The private key is generated by the owner and kept secret. It should never be shared or revealed to anyone else. The owner of the private key can use it to decrypt the data that has been encrypted with their corresponding public key.

F. The private key is used to decrypt the message that was encrypted by the public key. When the recipient receives the encrypted data, they use their private key to decrypt the data. This process ensures that only the intended recipient can access the data. The public key, on the other hand, is used to encrypt the data and can be shared with anyone who wants to send encrypted data to the owner of the private key.

A. The RSA algorithm provides encryption and authentication and B. The RSA algorithm provides authentication but not encryption are both false statements. Although RSA can be used for digital signatures to provide authentication, it does not provide authentication directly. And although RSA can be used for encryption, it does not provide message authentication or integrity, which is essential for secure communication.

E. The public key is used to decrypt the message that was encrypted by the private key is also a false statement. The public key is used for encryption, and the private key is used for decryption.

In summary, the RSA algorithm uses a public-private key pair to encrypt and decrypt data, and only the owner of the private key can decrypt the data that has been encrypted with their corresponding public key.