200-201 Security Concepts Practice Question
A company's security policy requires that sensitive data be encrypted at rest using AES-256. Which type of encryption does AES-256 represent?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Symmetric encryption
AES is a symmetric encryption algorithm, meaning the same key is used for encryption and decryption.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Hashing algorithm
Why it's wrong here
Hashing is one-way and not reversible; AES is reversible with the key.
- ✗
Digital signature
Why it's wrong here
Digital signatures use asymmetric encryption for authentication.
- ✗
Asymmetric encryption
Why it's wrong here
AES is symmetric, not asymmetric. RSA is an example of asymmetric.
- ✓
Symmetric encryption
Why this is correct
AES is a symmetric block cipher.
Quick reference
Symmetric Encryption Algorithm Comparison
| Algorithm | Key Size | Block Size | Status | Notes |
|---|---|---|---|---|
| AES-128 | 128-bit | 128-bit | Current standard | NIST approved; WPA3, TLS |
| AES-256 | 256-bit | 128-bit | Current standard | Preferred for sensitive / govt data |
| 3DES | 112-bit effective | 64-bit | Deprecated (2023) | Replaced by AES |
| DES | 56-bit | 64-bit | Broken | Cracked in < 24 h; never deploy |
| ChaCha20 | 256-bit | Stream cipher | Current | TLS 1.3, WireGuard |
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JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This 200-201 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 200-201 exam.