200-301 Question 138
Single answerA network administrator is tasked with securing data transmitted between two branch offices over an untrusted WAN connection. The solution must ensure that data remains confidential and cannot be read by unauthorized parties. Which type of encryption mechanism should the administrator implement?
- A
Symmetric encryption with a pre-shared key
- B
Asymmetric encryption using digital signatures only
- C
Hashing algorithms like MD5 or SHA-256
- D
Symmetric encryption combined with IPsec VPN
Show answer and explanation
Correct answer: D
Explanation
The correct answer is 'Symmetric encryption combined with IPsec VPN' because IPsec provides a secure framework for encrypting data using symmetric encryption algorithms while also offering integrity and authentication mechanisms. This ensures that data is protected from unauthorized access and tampering while being transmitted across an untrusted WAN connection.
- A. Incorrect.
Symmetric encryption with a pre-shared key can provide confidentiality, but it does not secure the transmission over the WAN connection by itself. Additional mechanisms like VPN are required.
- B. Incorrect.
Asymmetric encryption using digital signatures only is used for authentication and integrity, not for encrypting data for confidentiality.
- C. Incorrect.
Hashing algorithms like MD5 or SHA-256 provide data integrity but do not encrypt data and hence cannot ensure confidentiality.
- D. Correct.
Symmetric encryption combined with IPsec VPN ensures confidentiality, integrity, and secure transmission over an untrusted network like a WAN.