- A
IPsec
Why wrong: IPsec is not used for VXLAN encapsulation.
- B
TCP
Why wrong: TCP is not used for VXLAN.
- C
GRE
Why wrong: GRE is not used for VXLAN.
- D
UDP
VXLAN uses UDP (port 4789).
Question 144 of 1,000
350-601 Network Practice Question
This 350-601 practice question tests your understanding of network. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
In a VXLAN overlay, which encapsulation is used to transport Ethernet frames over the IP network?
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
✓
UDP
VXLAN uses UDP encapsulation (destination port 4789 by default) to transport Layer 2 Ethernet frames over a Layer 3 IP network. This allows the overlay to leverage existing IP routing infrastructure while preserving the original MAC addresses and VLAN information, enabling network virtualization and scalability beyond traditional VLAN limits.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Cisco often tests the misconception that VXLAN uses GRE or TCP encapsulation because of its tunneling nature, but the key is that VXLAN specifically uses UDP to allow stateless, scalable overlay transport and to leverage existing IP routing without TCP's connection overhead.
Detailed technical explanation
How to think about this question
VXLAN encapsulates the original Ethernet frame in a UDP packet with a VXLAN header (8 bytes) containing a 24-bit VNI (VXLAN Network Identifier) that supports up to 16 million logical networks. The UDP source port is typically computed from a hash of the inner packet headers to enable entropy-based load balancing across ECMP paths in the underlay network, while the destination port is fixed at 4789 (IANA assigned) or 8472 (Linux default).
KKey Concepts to Remember
- Read the scenario before looking for a memorised answer.
- Find the constraint that changes the correct option.
- Eliminate answers that are true in general but not in this case.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A help-desk technician troubleshoots why a newly connected PC cannot reach shared printers on the same floor. The cable is good, the switch port is active, but the PC is in VLAN 20 and the printers are in VLAN 10. The uplink trunk only allows VLAN 10. A trunk being up does not mean every VLAN crosses it.
Visual reference
Quick reference
OSI Model Reference
| Layer | Name | PDU | Key Protocols / Devices |
|---|---|---|---|
| 7 | Application | Data | HTTP, HTTPS, DNS, SMTP, FTP, SSH |
| 6 | Presentation | Data | TLS / SSL, JPEG, ASCII encoding |
| 5 | Session | Data | NetBIOS, RPC, SIP |
| 4 | Transport | Segment / Datagram | TCP, UDP |
| 3 | Network | Packet | IP, ICMP, OSPF — Routers |
| 2 | Data Link | Frame | Ethernet, Wi-Fi, PPP — Switches, Bridges |
| 1 | Physical | Bits | Cables, NICs, Hubs, Repeaters |
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
Network — study guide chapter
Learn the concepts, then practise the questions
- →
Network practice questions
Targeted practice on this topic area only
- →
All 350-601 questions
1,000 questions across all exam domains
- →
Cisco DCCOR / CCNP Data Center Core 350-601 study guide
Full concept coverage aligned to exam objectives
- →
350-601 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related 350-601 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Security practice questions
Practise 350-601 questions linked to Security.
Network practice questions
Practise 350-601 questions linked to Network.
Storage Network practice questions
Practise 350-601 questions linked to Storage Network.
Automation practice questions
Practise 350-601 questions linked to Automation.
Compute practice questions
Practise 350-601 questions linked to Compute.
350-601 fundamentals practice questions
Practise 350-601 questions linked to 350-601 fundamentals.
350-601 scenario practice questions
Practise 350-601 questions linked to 350-601 scenario.
350-601 troubleshooting practice questions
Practise 350-601 questions linked to 350-601 troubleshooting.
Practice this exam
Start a free 350-601 practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this 350-601 question test?
Network — This question tests Network — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: UDP — VXLAN uses UDP encapsulation (destination port 4789 by default) to transport Layer 2 Ethernet frames over a Layer 3 IP network. This allows the overlay to leverage existing IP routing infrastructure while preserving the original MAC addresses and VLAN information, enabling network virtualization and scalability beyond traditional VLAN limits.
What should I do if I get this 350-601 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Keep practising
More 350-601 practice questions
- In Cisco ACI, which component is responsible for translating EPG communication policies into concrete configuration on l…
- An engineer is configuring OSPF on a Cisco Nexus switch in a data center. The network consists of multiple point-to-poin…
- An engineer is configuring BGP EVPN for VXLAN in a spine-leaf fabric. The leaf switches must advertise host IP-to-MAC ma…
- Which VLAN range is reserved by default on Cisco Nexus switches?
- In VXLAN overlay networks, which mechanism is used to forward broadcast, unknown unicast, and multicast (BUM) traffic wh…
- Which command is used to verify the OSPF neighbor state in NX-OS?
Last reviewed: Jul 4, 2026
This 350-601 practice question is part of Courseiva's free Cisco 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 350-601 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.