1. What is Symmetric encryption ? Junior A. function like PBKDF2, bcrypt, scrypt, or Argon2 that slowly derives keys/password hashes to resist brute force B. adding a unique random value to each password before hashing to defeat precomputed/rainbow-table attacks C. asymmetric crypto over elliptic curves giving strong security with smaller keys than RSA D. encryption using the same secret key to encrypt and decrypt (e.g. AES)
2. Which term means: "encryption using the same secret key to encrypt and decrypt (e.g. AES)"? Junior A. Symmetric encryption B. Hashing vs encryption C. Hash collision D. Plaintext
3. Which statement is correct? Junior A. Symmetric encryption — encryption using the same secret key to encrypt and decrypt (e.g. AES) B. Symmetric encryption — algorithms (e.g. ML-KEM/Kyber, ML-DSA) designed to resist attacks from quantum computers C. Symmetric encryption — property where session keys are ephemeral so compromise of a long-term key cannot decrypt past sessions D. Symmetric encryption — data signed with a private key that anyone can verify with the public key for authenticity and integrity
4. What is Asymmetric encryption ? Junior A. the original readable data before it is encrypted B. encryption using a public/private key pair, where one key encrypts and the other decrypts (e.g. RSA, ECC) C. adding a unique random value to each password before hashing to defeat precomputed/rainbow-table attacks D. a 256-bit cryptographic hash from the SHA-2 family, widely used for integrity and signatures
5. Which term means: "encryption using a public/private key pair, where one key encrypts and the other decrypts (e.g. RSA, ECC)"? Junior A. Asymmetric encryption B. Key exchange C. Key derivation function (KDF) D. HMAC
6. Which statement is correct? Junior A. Asymmetric encryption — key-agreement algorithm letting parties derive a shared secret without transmitting it B. Asymmetric encryption — encryption using a public/private key pair, where one key encrypts and the other decrypts (e.g. RSA, ECC) C. Asymmetric encryption — two distinct inputs producing the same hash digest, undermining integrity guarantees D. Asymmetric encryption — keyed-hash message authentication code providing integrity and authenticity using a shared secret
7. What is Hashing ? Junior A. cipher that encrypts data one bit or byte at a time using a keystream (e.g. ChaCha20) B. a number used once to prevent replay attacks and ensure uniqueness in a cryptographic operation C. one-way function mapping arbitrary data to a fixed-size digest that cannot be reversed D. encoding (e.g. Base64) is reversible without a key and provides no confidentiality, unlike encryption
8. Which term means: "one-way function mapping arbitrary data to a fixed-size digest that cannot be reversed"? Junior A. Nonce B. Hashing C. Stream cipher D. Post-quantum cryptography
9. Which statement is correct? Junior A. Hashing — a 256-bit cryptographic hash from the SHA-2 family, widely used for integrity and signatures B. Hashing — data signed with a private key that anyone can verify with the public key for authenticity and integrity C. Hashing — one-way function mapping arbitrary data to a fixed-size digest that cannot be reversed D. Hashing — property where session keys are ephemeral so compromise of a long-term key cannot decrypt past sessions
10. What is AES ? Junior A. memory-hard password hashing algorithm and winner of the Password Hashing Competition, recommended for new systems B. Advanced Encryption Standard, a widely used symmetric block cipher with 128/192/256-bit keys C. one-way function mapping arbitrary data to a fixed-size digest that cannot be reversed D. a random value combined with a key so identical plaintext blocks encrypt to different ciphertext
11. Which term means: "Advanced Encryption Standard, a widely used symmetric block cipher with 128/192/256-bit keys"? Junior A. Nonce B. Diffie-Hellman C. Symmetric encryption D. AES
12. Which statement is correct? Junior A. AES — algorithms (e.g. ML-KEM/Kyber, ML-DSA) designed to resist attacks from quantum computers B. AES — Advanced Encryption Standard, a widely used symmetric block cipher with 128/192/256-bit keys C. AES — key-agreement algorithm letting parties derive a shared secret without transmitting it D. AES — the original readable data before it is encrypted
13. What is SHA-256 ? Junior A. adding a unique random value to each password before hashing to defeat precomputed/rainbow-table attacks B. a random value combined with a key so identical plaintext blocks encrypt to different ciphertext C. a 256-bit cryptographic hash from the SHA-2 family, widely used for integrity and signatures D. data signed with a private key that anyone can verify with the public key for authenticity and integrity
14. Which term means: "a 256-bit cryptographic hash from the SHA-2 family, widely used for integrity and signatures"? Junior A. SHA-256 B. Diffie-Hellman C. Padding oracle attack D. ECB mode weakness
15. Which statement is correct? Junior A. SHA-256 — encryption using a public/private key pair, where one key encrypts and the other decrypts (e.g. RSA, ECC) B. SHA-256 — a 256-bit cryptographic hash from the SHA-2 family, widely used for integrity and signatures C. SHA-256 — periodically replacing cryptographic keys to limit exposure from a potential compromise D. SHA-256 — Advanced Encryption Standard, a widely used symmetric block cipher with 128/192/256-bit keys
16. What is Encoding vs encryption ? Junior A. two distinct inputs producing the same hash digest, undermining integrity guarantees B. encoding (e.g. Base64) is reversible without a key and provides no confidentiality, unlike encryption C. a number used once to prevent replay attacks and ensure uniqueness in a cryptographic operation D. the scrambled output produced by encrypting plaintext
17. Which term means: "encoding (e.g. Base64) is reversible without a key and provides no confidentiality, unlike encryption"? Junior A. Plaintext B. Perfect forward secrecy C. HMAC D. Encoding vs encryption
18. Which statement is correct? Junior A. Encoding vs encryption — adding a unique random value to each password before hashing to defeat precomputed/rainbow-table attacks B. Encoding vs encryption — encoding (e.g. Base64) is reversible without a key and provides no confidentiality, unlike encryption C. Encoding vs encryption — memory-hard password hashing algorithm and winner of the Password Hashing Competition, recommended for new systems D. Encoding vs encryption — encryption using the same secret key to encrypt and decrypt (e.g. AES)
19. What is Salting ? Mid A. adding a unique random value to each password before hashing to defeat precomputed/rainbow-table attacks B. exploiting decryption error responses to recover plaintext from CBC-mode ciphertext C. protocol allowing two parties to agree on a shared secret over an insecure channel (e.g. Diffie-Hellman) D. encoding (e.g. Base64) is reversible without a key and provides no confidentiality, unlike encryption
20. Which term means: "adding a unique random value to each password before hashing to defeat precomputed/rainbow-table attacks"? Mid A. Diffie-Hellman B. Authenticated encryption (AEAD) C. Salting D. Block cipher
21. Which statement is correct? Mid A. Salting — two distinct inputs producing the same hash digest, undermining integrity guarantees B. Salting — encoding (e.g. Base64) is reversible without a key and provides no confidentiality, unlike encryption C. Salting — adding a unique random value to each password before hashing to defeat precomputed/rainbow-table attacks D. Salting — a random value combined with a key so identical plaintext blocks encrypt to different ciphertext
22. What is HMAC ? Mid A. keyed-hash message authentication code providing integrity and authenticity using a shared secret B. cipher that encrypts data one bit or byte at a time using a keystream (e.g. ChaCha20) C. function like PBKDF2, bcrypt, scrypt, or Argon2 that slowly derives keys/password hashes to resist brute force D. cipher that encrypts fixed-size blocks of data, requiring a mode of operation for longer messages
23. Which term means: "keyed-hash message authentication code providing integrity and authenticity using a shared secret"? Mid A. Stream cipher B. Block cipher C. Initialization Vector (IV) D. HMAC
24. Which statement is correct? Mid A. HMAC — asymmetric crypto over elliptic curves giving strong security with smaller keys than RSA B. HMAC — periodically replacing cryptographic keys to limit exposure from a potential compromise C. HMAC — hashing is one-way and keyless; encryption is reversible with the correct key D. HMAC — keyed-hash message authentication code providing integrity and authenticity using a shared secret
25. What is Digital signature ? Mid A. algorithms (e.g. ML-KEM/Kyber, ML-DSA) designed to resist attacks from quantum computers B. encryption using a public/private key pair, where one key encrypts and the other decrypts (e.g. RSA, ECC) C. adding a unique random value to each password before hashing to defeat precomputed/rainbow-table attacks D. data signed with a private key that anyone can verify with the public key for authenticity and integrity
26. Which term means: "data signed with a private key that anyone can verify with the public key for authenticity and integrity"? Mid A. Digital signature B. Nonce C. Perfect forward secrecy D. Key rotation
27. Which statement is correct? Mid A. Digital signature — cipher that encrypts fixed-size blocks of data, requiring a mode of operation for longer messages B. Digital signature — two distinct inputs producing the same hash digest, undermining integrity guarantees C. Digital signature — data signed with a private key that anyone can verify with the public key for authenticity and integrity D. Digital signature — a random value combined with a key so identical plaintext blocks encrypt to different ciphertext
28. What is Nonce ? Mid A. hashing is one-way and keyless; encryption is reversible with the correct key B. a number used once to prevent replay attacks and ensure uniqueness in a cryptographic operation C. keyed-hash message authentication code providing integrity and authenticity using a shared secret D. cipher that encrypts data one bit or byte at a time using a keystream (e.g. ChaCha20)
29. Which term means: "a number used once to prevent replay attacks and ensure uniqueness in a cryptographic operation"? Mid A. Hashing B. Nonce C. Initialization Vector (IV) D. Argon2
30. Which statement is correct? Mid A. Nonce — a number used once to prevent replay attacks and ensure uniqueness in a cryptographic operation B. Nonce — two distinct inputs producing the same hash digest, undermining integrity guarantees C. Nonce — algorithms (e.g. ML-KEM/Kyber, ML-DSA) designed to resist attacks from quantum computers D. Nonce — cipher that encrypts fixed-size blocks of data, requiring a mode of operation for longer messages Showing 30 of 84 Crypto · Fundamentals questions — the full set, with answers, explanations and an AI tutor on every question, is inside.