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SSCP Practice Question: Is implementing a new remote access VPN for…
An organization is implementing a new remote access VPN for employees using IPsec. Which TWO of the following are best practices for securing the IPsec VPN?
⚠ Common exam trap
Watch out — candidates often confuse pre-shared keys as a secure authentication method for IPsec, but the SSCP exam emphasizes that PSKs are weak compared to digital certificates or EAP methods, especially in enterprise environments.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Use AES encryption with a minimum key size of 128 bits
AES encryption with a minimum key size of 128 bits is a best practice for IPsec VPNs because it provides strong, symmetric encryption that is resistant to known cryptographic attacks. AES-128 is approved by NIST and widely considered secure for protecting sensitive data over untrusted networks like the internet.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Use AES encryption with a minimum key size of 128 bits
Why this is correct
AES-128 is a strong, recommended encryption algorithm for IPsec.
- ✗
Use pre-shared keys for authentication
Why it's wrong here
Pre-shared keys are weaker and harder to manage than certificate-based authentication.
- ✗
Disable anti-replay protection to improve performance
Why it's wrong here
Anti-replay protection is a critical security function and should never be disabled.
- ✓
Enable Perfect Forward Secrecy (PFS)
Why this is correct
PFS ensures session keys are not derived from long-term keys, so compromise of one session key does not compromise future sessions.
- ✗
Allow all IP protocols through the VPN tunnel
Why it's wrong here
Allowing all protocols expands the attack surface; only necessary protocols should be permitted.
Quick reference
VPN Protocol Comparison
| Protocol | Port | Encryption | Authentication | Use Case |
|---|---|---|---|---|
| IKEv2 / IPsec | UDP 500 / 4500 | AES-256 | Certificates / PSK | Site-to-site & remote access |
| SSL / TLS VPN | TCP 443 | TLS 1.3 | Certificates / MFA | Clientless remote access |
| L2TP / IPsec | UDP 1701 | AES (IPsec) | PSK / Certificates | Legacy remote access |
| WireGuard | UDP 51820 | ChaCha20 | Public keys | Modern high-performance VPN |
| PPTP | TCP 1723 | MPPE (weak) | MS-CHAPv2 | Legacy — avoid in production |
PPTP is considered insecure. IKEv2/IPsec and SSL VPN are the current recommended options.
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About these practice questions
One of 920 original SSCP practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This SSCP practice question is part of Courseiva's free ISC2 certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the SSCP exam.