Computer Concepts Module 3 Practice Exam

Protecting data at rest relies on a fast, strong encryption method applied to stored files and blocks. AES, the Advanced Encryption Standard, is the typical choice because it is symmetric (the same key for encryption and decryption), offers strong security with 128/192/256-bit keys, and runs efficiently in software and hardware with modern processors. This efficiency is crucial for large volumes of stored data, making encryption practical for disks, databases, and backups. In contrast, TLS protects data as it moves across networks, not when it’s sitting on storage. RSA is a public-key algorithm mainly used to securely exchange keys or to sign data, not for bulk encryption of stored data. Diffie-Hellman is a key-exchange protocol used to establish a shared secret for symmetric encryption, but it does not itself encrypt data at rest.