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NSE4 · Question #330
NSE4 Question #330: Real Exam Question with Answer & Explanation
The correct answer is A: To detect intermediary NAT devices in the tunnel path.. NAT traversal (NAT-T) in IPsec is used to detect intermediary NAT devices in the tunnel path and to encapsulate ESP packets in UDP packets using port 4500 to pass through NAT.
Submitted by yousef_jo· Apr 18, 2026VPN and Routing
Question
What are the purposes of NAT traversal in IPsec? (Choose two.)
Options
- ATo detect intermediary NAT devices in the tunnel path.
- BTo encapsulate ESP packets in UDP packets using port 4500.
- CTo force a new DH exchange with each phase 2 re-key
- DTo dynamically change phase 1 negotiation mode to Aggressive.
Explanation
NAT traversal (NAT-T) in IPsec is used to detect intermediary NAT devices in the tunnel path and to encapsulate ESP packets in UDP packets using port 4500 to pass through NAT.
Common mistakes.
- C. NAT-T does not force a new Diffie-Hellman (DH) exchange with each Phase 2 re-key; DH exchanges are typically for Phase 1 key establishment.
- D. NAT-T does not dynamically change the Phase 1 negotiation mode; it typically operates with Main Mode and adjusts how packets are encapsulated for NAT compatibility.
Concept tested. IPsec NAT traversal (NAT-T) mechanism
Topics
#IPsec#NAT Traversal (NAT-T)#VPN#UDP encapsulation
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