Tiêu đề mcq COMPUTER NETWORK SECURITY.pdf ✅

Way to Polytechnic ● Way to Polytechnic COMPUTER NETWORK SECURITY UNIT-01 Attacks on computers and computer security 1. What is the primary goal of computer security? A) To ensure absolute protection against all types of attacks B) To minimize risks and protect computer systems and data from unauthorized access, alteration, or destruction C) To eliminate the need for security measures D) To maximize network speed and performance Answer: B) To minimize risks and protect computer systems and data from unauthorized access, alteration, or destruction 2. What is cryptography? A) The study of computer hardware B) The study of computer software C) The practice and study of techniques for secure communication D) The study of computer networks Answer: C) The practice and study of techniques for secure communication 3. What is the purpose of encryption in cryptography? A) To hide the data being transmitted B) To speed up data transmission C) To make data more vulnerable to attacks D) To compress data for storage Answer: A) To hide the data being transmitted 4. Which cryptographic technique involves replacing each letter in the plaintext with another letter according to a fixed system? A) Symmetric key cryptography B) Asymmetric key cryptography C) Substitution cipher D) Transposition cipher Answer: C) Substitution cipher 5. What is the key difference between symmetric and asymmetric key cryptography? A) Symmetric key cryptography uses a single key for encryption and decryption, while asymmetric key cryptography uses different keys for encryption and decryption.
Way to Polytechnic ● Way to Polytechnic B) Symmetric key cryptography uses different keys for encryption and decryption, while asymmetric key cryptography uses a single key for encryption and decryption. C) Symmetric key cryptography is more secure than asymmetric key cryptography. D) Asymmetric key cryptography is more efficient than symmetric key cryptography. Answer: A) Symmetric key cryptography uses a single key for encryption and decryption, while asymmetric key cryptography uses different keys for encryption and decryption. 6. What is the key size in cryptography? A) The size of the encryption algorithm B) The size of the plaintext C) The size of the message digest D) The size of the cryptographic key measured in bits Answer: D) The size of the cryptographic key measured in bits 7. Which type of attack involves intercepting communication between two parties with the intent of stealing information? A) Denial of Service (DoS) attack B) Man-in-the-Middle (MitM) attack C) Phishing attack D) SQL injection attack Answer: B) Man-in-the-Middle (MitM) attack 8. What is the principle of the operational model of network security? A) Prevention, detection, and response B) Speed, reliability, and efficiency C) Complexity, simplicity, and flexibility D) Hardware, software, and network Answer: A) Prevention, detection, and response 9. In a substitution cipher, what does encryption involve? A) Changing the order of characters in the plaintext B) Replacing each character in the plaintext with another character C) Changing the size of the plaintext D) Dividing the plaintext into blocks Answer: B) Replacing each character in the plaintext with another character 10. What type of attack involves flooding a network or server with excessive traffic, making it unavailable to its intended users? A) Man-in-the-Middle (MitM) attack

Way to Polytechnic ● Way to Polytechnic Answer: B) Phishing attack 16. Which cryptographic technique uses a pair of keys: a public key for encryption and a private key for decryption? A) Symmetric key cryptography B) Asymmetric key cryptography C) Substitution cipher D) Transposition cipher Answer: B) Asymmetric key cryptography 17. What is the primary goal of a substitution cipher? A) To change the order of characters in the plaintext B) To replace each character in the plaintext with another character C) To divide the plaintext into blocks D) To increase data size Answer: B) To replace each character in the plaintext with another character 18. Which type of attack involves exploiting vulnerabilities in SQL database queries to execute malicious SQL code? A) Man-in-the-Middle (MitM) attack B) Phishing attack C) Denial of Service (DoS) attack D) SQL injection attack Answer: D) SQL injection attack 19. What is the primary purpose of cryptography in computer security? A) To make data transmission faster B) To make data more accessible to unauthorized users C) To protect data confidentiality, integrity, and authenticity D) To increase data vulnerability Answer: C) To protect data confidentiality, integrity, and authenticity 20. Which cryptographic technique uses the same key for both encryption and decryption? A) Symmetric key cryptography B) Asymmetric key cryptography C) Substitution cipher D) Transposition cipher Answer: A) Symmetric key cryptography