Match each encryption standard or algorithm to its type.
Drag a concept onto its matching description — or click a concept then click the description.
Symmetric block cipher
Asymmetric public-key cryptosystem
Hash function (one-way)
Elliptic curve digital signature algorithm
Keyed-hash message authentication code
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
AES: Symmetric encryption algorithm
The correct matches are AES with symmetric encryption, RSA with asymmetric encryption, and SHA-256 with hashing. Common confusions include mistaking AES for asymmetric or RSA for symmetric.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
AES: Symmetric encryption algorithm
Why this is correct
AES is a symmetric block cipher standard, using the same key for encryption and decryption.
RSA: Symmetric encryption algorithm
Why it's wrong here
Incorrect — RSA is an asymmetric (public-key) encryption algorithm, not symmetric.
SHA-256: Hashing algorithm
Why this is correct
SHA-256 is a cryptographic hash function that produces a 256-bit digest.
AES: Asymmetric encryption algorithm
Why it's wrong here
Incorrect — AES is a symmetric algorithm, not asymmetric.
RSA: Asymmetric encryption algorithm
Why this is correct
RSA is an asymmetric encryption algorithm that uses a public/private key pair.
Quick reference
| 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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About these practice questions
This CAS-005 question is part of Courseiva's 968-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This CAS-005 practice question is part of Courseiva's free CompTIA 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 CAS-005 exam.