CompTIA CASP+ Practice Test

What should a security engineer implement to achieve forward secrecy without greatly impacting server performance?

1. Session-based keys

2. Offloading SSL to a dedicated server

3. Elliptic Curve Cryptography

4. Standard RSA keys

The correct answer is: Elliptic Curve Cryptography

To achieve forward secrecy, employing Elliptic Curve Cryptography (ECC) is an effective approach. Forward secrecy ensures that session keys are not compromised even if long-term keys are exposed. ECC supports the generation of ephemeral keys that are used for each session, which are not directly tied to the long-term keys. This means that even if an adversary were to gain access to the private key used for other sessions, they would not be able to decrypt past communications because the session keys are unique and transient. Moreover, ECC is computationally efficient compared to traditional methods like RSA, especially as key lengths increase to maintain security. The reduced computational overhead allows ECC to provide strong security assurances while minimizing performance impacts on the server, making it a preferable choice over the other methods for maintaining session confidentiality without significantly degrading server performance. Other methods, such as using session-based keys, might provide a level of security but would not inherently guarantee forward secrecy without proper implementation. Offloading SSL to a dedicated server can improve performance but does not directly relate to ensuring forward secrecy. Standard RSA keys, while secure and widely used, do not provide forward secrecy on their own since if the private key is compromised, all past sessions encrypted with it can be decrypted.