# Question 259 of 530 from exam 400-251: CCIE Security written exam

### Question

What are two uses of an RSA algorithm? (Choose two.)

### Answers

### Explanations

AB.

RSA algorithm is a widely used cryptographic algorithm that is based on public-key cryptography. The RSA algorithm uses the public key to encrypt data and the private key to decrypt the data. In addition to encryption and decryption, the RSA algorithm has other uses as well. Two of the most important uses are digital signature verification and data encryption.

Digital signature verification: Digital signature verification is the process of verifying the authenticity of a digital signature. Digital signatures are used to ensure that the data has not been tampered with and that the sender is who they claim to be. The RSA algorithm is used in digital signature verification to encrypt the hash of the message being sent. This creates a digital signature that can be decrypted using the sender's public key, thus verifying the sender's identity and the integrity of the message.

Data encryption: Data encryption is the process of encoding data so that it can only be read by authorized parties. The RSA algorithm is used in data encryption to encrypt the data using the recipient's public key. The recipient can then use their private key to decrypt the data. This ensures that the data is secure and can only be accessed by authorized parties.

Therefore, the correct answers to the question are A. Data encryption and B. Digital signature verification. The RSA algorithm is not used for shared key generation or message hashing.