200-201 Question 168
Single answerA cybersecurity analyst is configuring a secure communication channel between two systems and needs to ensure the confidentiality of the exchanged keys during the process. Which of the following methods is MOST appropriate for secure key exchange?
- A
Diffie-Hellman Key Exchange
- B
Plaintext transmission of keys over a secure network
- C
RSA-encrypted key exchange
- D
Using pre-shared keys (PSKs) without encryption
Show answer and explanation
Correct answer: A
Explanation
The Diffie-Hellman Key Exchange is a widely used cryptographic method for secure key exchange, especially when dealing with insecure communication channels. It allows two parties to establish a shared secret securely without transmitting the actual key, thereby protecting the key exchange process from interception. Other methods, such as plaintext transmission or using unencrypted pre-shared keys, fail to provide adequate security and expose the key to potential compromise.
- A. Correct.
Diffie-Hellman Key Exchange is specifically designed for securely exchanging cryptographic keys over an insecure channel. It ensures confidentiality by enabling parties to derive a shared secret without transmitting the actual key.
- B. Incorrect.
Transmitting keys in plaintext, even over a secure network, is not a best practice as it exposes the keys to potential compromise if the network security is breached.
- C. Incorrect.
While RSA can be used for encrypting keys, it is not the most efficient or commonly used method for real-time key exchange in modern systems compared to protocols like Diffie-Hellman.
- D. Incorrect.
Using pre-shared keys without encryption is highly insecure as it exposes the keys to interception and compromise during transmission.