Private Key Cryptography Overview Answers 1. What primarily determines the security of private key cryptography? A. The size of the data being encrypted B. The secrecy of the shared key C. The speed of the encryption process D. The complexity of the encryption algorithm Answer: The secrecy of the shared key (B) The security of private key cryptography relies entirely on the secrecy of the shared key. 2. Which of the following is a major challenge faced by private key cryptography? A. High computational requirements B. Large data handling capacity C. Complexity of the encryption algorithms D. Secure key distribution Answer: Secure key distribution (D) Secure key distribution is a critical challenge and a potential security bottleneck in private key cryptography. 3. In private key cryptography, what happens if the shared key gets compromised? A. Only the sender's data becomes vulnerable B. The receiver can still secure communications C. No impact on encrypted messages D. The entire system's security is at risk Answer: The entire system's security is at risk (D) Compromising the shared key compromises the entire system of private key cryptography. 4. Which of the following algorithms is NOT associated with private key cryptography? A. Diffie-Hellman Key Exchange B. Blowfish C. Data Encryption Standard (DES) D. Advanced Encryption Standard (AES) Answer: Diffie-Hellman Key Exchange (A) Diffie-Hellman Key Exchange is a method used in public key cryptography, not private key cryptography. 5. Why is private key cryptography preferred for bulk data encryption? A. It is slower and more secure than public key cryptography B. It requires fewer resources to implement C. It is high speed and efficient for large datasets D. It offers the best security features available Answer: It is high speed and efficient for large datasets (C) Private key cryptography is high-speed and efficient, making it preferable for bulk data encryption. 6. What is a significant disadvantage of private key cryptography compared to public key cryptography? A. Need for pre-existing secure key exchange channels B. Higher costs associated with algorithms C. Slower encryption and decryption processes D. Incompatibility with modern security standards Answer: Need for pre-existing secure key exchange channels (A) Private key cryptography is less suitable for situations where there is no preexisting secure key exchange channel. 7. What process does the sender follow in private key cryptography? A. They encrypt the message without using a key. B. They use a shared key to transform plaintext into ciphertext. C. They send the plaintext directly without encryption. D. They encrypt with a public key and decrypt with a private key. Answer: They use a shared key to transform plaintext into ciphertext. (B) The sender uses the shared secret key to transform the plaintext into ciphertext in private key cryptography. 8. Which application is commonly associated with private key cryptography? A. Digital signatures for document verification B. Asymmetric encryption for secure key management C. Secure email exchange using public keys D. Encrypting sensitive data stored in databases Answer: Encrypting sensitive data stored in databases (D) Private key cryptography is widely used for encrypting sensitive data stored in databases and other applications.