FORTINET-NSE123 Practice Question: Nse 2 Technical Introduction TO Fortinet Security
Which THREE parameters must be configured identically on both peers to successfully establish an IPsec Phase 1 tunnel? (Choose three.)
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
✓
Encryption and hashing algorithms (e.g., AES-256 and SHA-256)
IPsec Phase 1 requires matching authentication methods (like pre-shared keys), encryption/hash algorithms, and Diffie-Hellman groups.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
System time zone offset in hours
Why it's wrong here
Time zones affect local log display, whereas cryptographic negotiations rely on UTC timestamps/epochs.
- ✓
Encryption and hashing algorithms (e.g., AES-256 and SHA-256)
Why this is correct
Phase 1 encryption and hashing proposals must match on both ends.
- ✓
Authentication method and Pre-Shared Key (or certificates)
Why this is correct
Peers must agree on the authentication method and share the identical PSK.
- ✓
Diffie-Hellman (DH) group
Why this is correct
Both peers must use the same DH group to derive shared cryptographic keys securely.
- ✗
FortiGate administrator username
Why it's wrong here
Admin usernames are local management accounts and play no role in IPsec VPN negotiations.
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.
About these practice questions
One of 296 original FORTINET-NSE123 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 and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed August 2026 · checked against the official Fortinet exam blueprint
This FORTINET-NSE123 practice question is part of Courseiva's free Fortinet 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 FORTINET-NSE123 exam.