Question 1mediumdrag order
Read the full MPLS explanation →Question 739 of 2,015
Quick Answer
The correct order for MPLS TE tunnel setup using RSVP begins with IGP extension flooding, followed by CSPF path computation, then the RSVP Path message, the RSVP Resv message, and finally the tunnel being signaled and installed in the forwarding table. This sequence is correct because RSVP-TE relies on OSPF or IS-IS to first advertise link attributes like bandwidth and affinity, allowing Constrained Shortest Path First (CSPF) to calculate an optimal path that meets traffic engineering constraints. The RSVP Path message then travels hop-by-hop along that computed path, and the RSVP Resv message flows back upstream to reserve resources and establish label-switched path state. On the ENCOR 350-401 exam, this drag-and-drop task tests your understanding of the control plane signaling flow, and a common trap is placing the CSPF computation after the Path message, which is incorrect because the path must be calculated before signaling begins. A helpful memory tip is to think of the acronym “ICPRT”: IGP flood, CSPF compute, Path send, Resv return, Tunnel installed.
350-401 MPLS Practice Question
This 350-401 practice question tests your understanding of mpls. 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.
Drag and drop the steps of MPLS Traffic Engineering (TE) tunnel setup (RSVP) into the correct order, from first to last.
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue:
"first"Why it matters: Order matters here. You are being tested on which action comes before the others — not which action is generally useful.
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
✓
IGP floods TE link attributes (bandwidth, affinity)
MPLS TE tunnel setup using RSVP begins with IGP extension (OSPF/IS-IS) to flood TE link attributes, then CSPF computes the path, RSVP Path message is sent, RSVP Resv message reserves resources, and finally the tunnel is signaled and installed in the forwarding table.
Key principle: OSPF neighbour adjacency depends on matching area, hello/dead timers, network type, and authentication — IP reachability alone is not enough.
Common exam traps
Common exam trap: OSPF can fail even when IP connectivity looks correct
OSPF neighbour formation depends on matching areas, timers, network type, authentication and passive-interface behaviour. Do not choose an answer only because the devices can ping.
Detailed technical explanation
How to think about this question
OSPF questions usually test the details that control adjacency and route selection. Read the neighbour state, area, router ID and interface configuration before deciding what is wrong.
KKey Concepts to Remember
- OSPF neighbours must agree on key parameters.
- Router ID selection can affect neighbour relationships and LSDB output.
- OSPF cost influences the preferred path.
- A route can appear in OSPF information but not become the installed route.
TExam Day Tips
- Check area mismatch first when OSPF adjacency fails.
- Review passive interfaces when a network is advertised but no neighbour forms.
- Use show ip ospf neighbor and show ip route clues carefully.
Key takeaway
OSPF neighbour adjacency depends on matching area, hello/dead timers, network type, and authentication — IP reachability alone is not enough.
Real-world example
How this comes up in practice
A network engineer at a university connects two campus buildings via a fibre link. Both routers run OSPF, but no adjacency forms — even though both routers can ping each other. The engineer finds one router is in area 0 and the other in area 1. OSPF adjacency requires matching area numbers, hello/dead timers, and network type. IP reachability alone is not enough.
What to study next
Got this wrong? Here's your next step.
Review OSPF neighbour requirements — matching area type, hello and dead timers, network type, stub flags, and authentication. Study show ip ospf neighbor states (INIT, 2-WAY, FULL). Then practise related 350-401 OSPF questions on adjacency and route selection.
- →
MPLS — study guide chapter
Learn the concepts, then practise the questions
- →
MPLS practice questions
Targeted practice on this topic area only
- →
All 350-401 questions
2,015 questions across all exam domains
- →
ENCOR 350-401 study guide
Full concept coverage aligned to exam objectives
- →
350-401 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related 350-401 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Architecture practice questions
Practise 350-401 questions linked to Architecture.
Enterprise Network Design practice questions
Practise 350-401 questions linked to Enterprise Network Design.
SD-Access Architecture practice questions
Practise 350-401 questions linked to SD-Access Architecture.
SD-WAN Architecture practice questions
Practise 350-401 questions linked to SD-WAN Architecture.
QoS Architecture practice questions
Practise 350-401 questions linked to QoS Architecture.
Virtualization practice questions
Practise 350-401 questions linked to Virtualization.
Network Function Virtualization practice questions
Practise 350-401 questions linked to Network Function Virtualization.
Virtual Machines and Hypervisors practice questions
Practise 350-401 questions linked to Virtual Machines and Hypervisors.
VRF and Path Isolation practice questions
Practise 350-401 questions linked to VRF and Path Isolation.
Infrastructure practice questions
Practise 350-401 questions linked to Infrastructure.
OSPF practice questions
Practise 350-401 questions linked to OSPF.
BGP practice questions
Practise 350-401 questions linked to BGP.
Practice this exam
Start a free 350-401 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 350-401 question test?
MPLS — This question tests MPLS — OSPF neighbours must agree on key parameters..
What is the correct answer to this question?
The correct answer is: IGP floods TE link attributes (bandwidth, affinity) — MPLS TE tunnel setup using RSVP begins with IGP extension (OSPF/IS-IS) to flood TE link attributes, then CSPF computes the path, RSVP Path message is sent, RSVP Resv message reserves resources, and finally the tunnel is signaled and installed in the forwarding table.
What should I do if I get this 350-401 question wrong?
Review OSPF neighbour requirements — matching area type, hello and dead timers, network type, stub flags, and authentication. Study show ip ospf neighbor states (INIT, 2-WAY, FULL). Then practise related 350-401 OSPF questions on adjacency and route selection.
Are there clue words in this question I should notice?
Yes — watch for: "first". Order matters here. You are being tested on which action comes before the others — not which action is generally useful.
What is the key concept behind this question?
OSPF neighbours must agree on key parameters.
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 →
Same concept, more angles
2 more ways this is tested on 350-401
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. Drag and drop the steps of MPLS traffic engineering (MPLS-TE) tunnel setup into the correct order, from first to last.
medium- ✓ A.Configure IGP with TE extensions (OSPF TE or IS-IS TE)
- ✓ B.Enable MPLS-TE on all participating interfaces
- ✓ C.Headend runs CSPF to compute explicit path
- ✓ D.Configure tunnel interface with destination and constraints
- ✓ E.RSVP-TE signals LSP and reserves bandwidth
Why A: First, IGP must be configured with TE extensions (e.g., OSPF TE) to flood link attributes. Then MPLS-TE is enabled on interfaces. The headend router computes a path using CSPF based on constraints. The tunnel interface is configured with the destination and constraints. Finally, RSVP-TE signals the LSP and reserves bandwidth along the path.
Variation 2. Drag and drop the steps of MPLS Traffic Engineering (TE) tunnel setup (RSVP) into the correct order, from first to last.
medium- ✓ A.Configure IGP extensions (OSPF/IS-IS) for TE
- ✓ B.Define explicit path on head-end router
- ✓ C.Head-end sends RSVP PATH message
- ✓ D.Intermediate routers process PATH and reserve resources
- ✓ E.Tail-end replies with RSVP RESV message
Why A: MPLS TE tunnel setup begins with IGP extension configuration to propagate link attributes, followed by explicit path definition. RSVP-TE then signals the tunnel using PATH messages, which are processed by intermediate routers to reserve bandwidth. Finally, RESV messages confirm the reservation and establish the tunnel.
Last reviewed: Jun 18, 2026
This 350-401 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 350-401 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.