Match each cryptographic term to its description.
Drag a concept onto its matching description — or click a concept then click the description.
Uses same key for encryption and decryption
Uses public/private key pair
One-way transformation producing fixed-size digest
Provides authenticity and non-repudiation
Framework managing digital certificates and keys
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
Symmetric Encryption: Uses a single shared key for both encryption and decryption
The correct matches are: Symmetric Encryption uses a shared key, Asymmetric Encryption uses a key pair, and Hash Function produces a one-way digest. Distractors confuse the purpose of digital signatures and the nature of PKI.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
Symmetric Encryption: Uses a single shared key for both encryption and decryption
Why this is correct
Symmetric encryption uses the same key for both encryption and decryption, ensuring confidentiality between parties that share the key.
Asymmetric Encryption: Uses a pair of keys (public and private) for encryption and decryption
Why this is correct
Asymmetric encryption employs a public-private key pair, where the public key encrypts and the private key decrypts, enabling secure key exchange.
Hash Function: Converts data into a fixed-length digest that is infeasible to reverse
Why this is correct
A hash function produces a fixed-size output from variable input, and it is a one-way function, making reversal computationally infeasible.
Digital Signature: Ensures confidentiality of data
Why it's wrong here
Incorrect — digital signatures provide authentication and non-repudiation, not confidentiality. Confidentiality is ensured by encryption.
Public Key Infrastructure (PKI): Uses a single shared key for both encryption and decryption
Why it's wrong here
Incorrect — PKI is a framework for managing digital certificates and public-key encryption, not symmetric encryption. A single shared key describes symmetric encryption.
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 |
Go deeper
About these practice questions
One of 871 original CISM practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This CISM practice question is part of Courseiva's free ISACA 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 CISM exam.