CompTIA Cloud+ Practice Test

In the context of digital certificates, what is a core function of public-key cryptography?

1. To ensure data integrity

2. To facilitate secure data storage

3. To enable secure key exchange

4. To create backups of data

The correct answer is: To enable secure key exchange

Public-key cryptography plays a crucial role in enabling secure key exchange, which is fundamental to establishing secure communications over potentially insecure channels. In this cryptographic approach, each participant has a pair of keys: a public key, which can be shared openly, and a private key, which is kept secret. When one party wants to send a secure message, they can use the recipient's public key to encrypt the data. Only the recipient, who possesses the corresponding private key, can decrypt this message. This method not only ensures that the information can only be read by the intended recipient but also protects the key exchange process itself from being intercepted or accessed by unauthorized users. While public-key cryptography contributes to ensuring data integrity and facilitating secure data storage, its primary and distinctive function in this context is to enable a secure mechanism for exchanging keys. This feature is essential to creating secure connections and is foundational for various security protocols used across digital communications.