Forward secrecy (also known as perfect forward secrecy, PFS) ensures that session keys used in a VPN tunnel are ephemeral, meaning that even if an attacker compromises a long-term private key, past sessions cannot be decrypted. According to the CompTIA SecurityX CAS-005 study guide (Domain 3: Cybersecurity Technology, 3.1), enabling forward secrecy on VPN tunnels reduces the risk of cryptanalysis by ensuring that each session’s encryption key is unique and not derived from a single compromised key. This directly mitigates the impact of attacks like key theft or future decryption attempts.
Option A:Forward secrecy is not required for hardware-accelerated cryptography, which depends on processor capabilities, not key management.
Option C:While confidentiality is important, this is too vague and does not specifically explain why forward secrecy is chosen.
Option D:Modern protocols (e.g., TLS 1.3, IPsec with ECDHE) support forward secrecy but donot mandate it as a prerequisite for use.
Option B:This is the most precise, as forward secrecy directly reduces the success of cryptanalysis by limiting the scope of key compromise.
[Reference:, CompTIA SecurityX CAS-005 Official Study Guide, Domain 3: Cybersecurity Technology, Section 3.1: "Explain cryptographic techniques, including perfect forward secrecy.", CAS-005 Exam Objectives, 3.1: "Evaluate the impact of cryptographic configurations on security.", , , ]
