Introduction to Hashing Answers 1. What is a primary advantage of using SHA-256, SHA-384, and SHA512 over MD5 and SHA-1? A. They are universally accepted standards. B. They require less memory. C. They offer better security. D. They are easier to compute. Answer: They offer better security. (C) SHA-256, SHA-384, and SHA-512 are advancements that provide improved security features compared to MD5 and SHA-1. 2. Which property ensures that it is computationally infeasible to find two different inputs that produce the same hash? A. Hash agility B. Collision resistance C. Second-preimage resistance D. Pre-image resistance Answer: Collision resistance (B) Collision resistance is crucial for the security of a hash function, preventing the occurrence of identical hash outputs from different inputs. 3. What is MurmurHash primarily designed for? A. High security in cryptographic applications. B. Storing sensitive data securely. C. Speed and uniformity in hash tables. D. Generating keys for encryption. Answer: Speed and uniformity in hash tables. (C) MurmurHash is focused on providing fast performance and even distribution, making it suitable for hash table implementations. 4. In which scenario is Jenkins Hash particularly applicable? A. For hashing large files for integrity checking. B. In applications requiring reversible hashing. C. When extensive cryptographic security is needed. D. In embedded systems where speed and memory efficiency are priorities. Answer: In embedded systems where speed and memory efficiency are priorities. (D) Jenkins Hash is designed for applications that prioritize efficient performance and memory use, which is common in embedded systems. 5. Which aspect of hashing is crucial for ensuring the security of sensitive data like passwords? A. Applying collision resistance techniques. B. Selecting a reliable hash function like MD5. C. Using linear probing for hash tables. D. Achieving faster hashing speeds. Answer: Applying collision resistance techniques. (A) Ensuring collision resistance is vital when hashing sensitive information to prevent vulnerabilities in data storage. 6. What is the main purpose of a hash function in data retrieval operations? A. To encrypt sensitive data B. To map data of arbitrary size to fixed-size values C. To compress large datasets D. To store data in multiple locations Answer: To map data of arbitrary size to fixed-size values (B) Hash functions are primarily used to map data of arbitrary size to fixed-size values for efficient retrieval. 7. Which property of a hash function ensures that the same input will always produce the same output? A. Avalanche effect B. Efficiency C. Deterministic D. Uniformity Answer: Deterministic (C) The deterministic property guarantees that identical inputs yield identical outputs. 8. What type of data structure employs a hash function to store keyvalue pairs? A. Hash table B. Stack C. Array D. Heap Answer: Hash table (A) A hash table uses a hash function to compute an index for storing key-value pairs. 9. Which of the following best describes a collision in a hash table? A. When the hash table is full B. When two identical keys are stored C. When an index does not store a key-value pair D. When two different keys map to the same index Answer: When two different keys map to the same index (D) A collision occurs when two different keys produce the same index in a hash table. 10. What strategy involves storing a linked list at each index of a hash table to handle collisions? A. Open addressing B. Direct addressing C. Linked hashing D. Chaining Answer: Chaining (D) Chaining allows multiple key-value pairs to be stored at the same index using linked lists. 11. Which application of hashing is specifically related to ensuring data integrity and security? A. Database indexing B. Cryptography C. Content addressing D. Data compression Answer: Cryptography (B) Cryptographic hashing is used to verify the integrity and security of data. 12. What is a significant drawback of the MD5 hashing algorithm? A. It is too computationally intensive B. It is now considered insecure due to vulnerabilities C. It produces outputs that are too large D. It is low in efficiency Answer: It is now considered insecure due to vulnerabilities (B) MD5 is widely used but now recognized as insecure for many applications. 13. What effect does a small change in input have on the output of a well-designed hash function? A. Significant change in the output B. No effect on the output C. Output becomes unpredictable D. Output changes slightly Answer: Significant change in the output (A) A small change in input should produce a significant change in output to enhance security.