Which encryption standard is recommended by NIST for securing classified information?
- DES
- 3DES
- AES-256
- RC4
Answer: AES-256
AES-256 (Advanced Encryption Standard with 256-bit key) is approved by NIST for top-secret information. Provides strong security against brute-force attacks. DES/3DES are deprecated; RC4 has known vulnerabilities. AES is efficient in both hardware and software implementations.