- A
YANG is a data modeling language used to define the structure of configuration and operational state data.
Correct because YANG (RFC 7950) is indeed a data modeling language for defining data structures, which are then used by telemetry to stream operational state.
- B
OpenConfig YANG models are vendor-specific and only supported on Cisco devices.
Why wrong: Incorrect because OpenConfig models are vendor-neutral, designed to work across multiple vendors, not just Cisco.
- C
Native YANG models are developed by the device vendor and may expose platform-specific features.
Correct because native models (e.g., Cisco IOS-XE native) are vendor-specific and can expose unique hardware or software capabilities not covered by standard models.
- D
IETF YANG models are the only models that can be used for model-driven telemetry subscriptions.
Why wrong: Incorrect because telemetry subscriptions can use any YANG model—native, OpenConfig, or IETF—as long as the device supports it.
- E
YANG is a transport protocol used to stream telemetry data from network devices to collectors.
Why wrong: Incorrect because YANG is a data modeling language, not a transport protocol. Telemetry data is transported using protocols like gRPC, HTTP/2, or UDP.
Quick Answer
The correct answer is that native YANG models are developed by the device vendor and may expose platform-specific features. This is true because YANG models define the structure and constraints of data for model-driven telemetry, and native models are purpose-built by vendors like Cisco to expose proprietary hardware capabilities or software features not covered by open standards. On the ENCOR 350-401 exam, this distinction tests your understanding of how telemetry subscriptions reference YANG paths—native models give you granular, vendor-specific data, while OpenConfig models prioritize multi-vendor consistency. A common trap is confusing “vendor-neutral” with “IETF models”; remember that IETF models are standards-based but not necessarily vendor-neutral, whereas OpenConfig is explicitly vendor-neutral. Memory tip: think “Native = Niche (vendor-specific), OpenConfig = Open (multi-vendor).”
CCNP Model-Driven Telemetry Practice Question
This 350-401 practice question tests your understanding of model-driven telemetry. 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.
Which two statements about YANG data models and their role in model-driven telemetry are true? (Choose two.)
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
YANG is a data modeling language used to define the structure of configuration and operational state data.
YANG models define the structure and constraints of data that can be streamed via telemetry. Native models are vendor-specific, while OpenConfig models are vendor-neutral. IETF models are standards-based but not necessarily vendor-neutral. YANG is a data modeling language, not a transport protocol. Telemetry subscriptions reference YANG paths to specify which data to stream.
Key principle: NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
YANG is a data modeling language used to define the structure of configuration and operational state data.
Why this is correct
Correct because YANG (RFC 7950) is indeed a data modeling language for defining data structures, which are then used by telemetry to stream operational state.
Related concept
Static NAT maps one inside address to one outside address.
- ✗
OpenConfig YANG models are vendor-specific and only supported on Cisco devices.
Why it's wrong here
Incorrect because OpenConfig models are vendor-neutral, designed to work across multiple vendors, not just Cisco.
- ✓
Native YANG models are developed by the device vendor and may expose platform-specific features.
Why this is correct
Correct because native models (e.g., Cisco IOS-XE native) are vendor-specific and can expose unique hardware or software capabilities not covered by standard models.
Related concept
Static NAT maps one inside address to one outside address.
- ✗
IETF YANG models are the only models that can be used for model-driven telemetry subscriptions.
Why it's wrong here
Incorrect because telemetry subscriptions can use any YANG model—native, OpenConfig, or IETF—as long as the device supports it.
- ✗
YANG is a transport protocol used to stream telemetry data from network devices to collectors.
Common exam traps
Common exam trap: NAT rules depend on direction and matching traffic
NAT is not only about the public address. The inside/outside interface roles and the ACL or rule that matches traffic are just as important.
Detailed technical explanation
How to think about this question
NAT questions usually test address translation, overload/PAT behaviour, static mappings and whether the right traffic is being translated. Read the interface direction and address terms carefully.
KKey Concepts to Remember
- Static NAT maps one inside address to one outside address.
- PAT allows many inside hosts to share one public address using ports.
- Inside local and inside global describe the private and translated addresses.
- NAT ACLs identify traffic for translation, not always security filtering.
TExam Day Tips
- Identify inside and outside interfaces first.
- Check whether the scenario needs static NAT, dynamic NAT or PAT.
- Do not confuse NAT matching ACLs with normal packet-filtering intent.
Key takeaway
NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
Real-world example
How this comes up in practice
A small business has 20 workstations on the 192.168.1.0/24 network and one public IP from its ISP. The router uses PAT (NAT overload) so all 20 devices share one public address using different source ports. NAT questions test whether you understand the four address terms and which direction each translation applies.
What to study next
Got this wrong? Here's your next step.
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related 350-401 NAT questions on configuration and troubleshooting.
- →
Model-Driven Telemetry — study guide chapter
Learn the concepts, then practise the questions
- →
Model-Driven Telemetry 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?
Model-Driven Telemetry — This question tests Model-Driven Telemetry — Static NAT maps one inside address to one outside address..
What is the correct answer to this question?
The correct answer is: YANG is a data modeling language used to define the structure of configuration and operational state data. — YANG models define the structure and constraints of data that can be streamed via telemetry. Native models are vendor-specific, while OpenConfig models are vendor-neutral. IETF models are standards-based but not necessarily vendor-neutral. YANG is a data modeling language, not a transport protocol. Telemetry subscriptions reference YANG paths to specify which data to stream.
What should I do if I get this 350-401 question wrong?
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related 350-401 NAT questions on configuration and troubleshooting.
What is the key concept behind this question?
Static NAT maps one inside address to one outside address.
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
1 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. Which two statements about YANG data models in model-driven telemetry are true? (Choose two.)
medium- ✓ A.YANG models are used to define the data structures streamed in telemetry subscriptions.
- ✓ B.OpenConfig YANG models are vendor-neutral and supported across multiple network operating systems.
- C.Native YANG models are standardized by the IETF and used universally.
- D.NETCONF is a YANG data model used for telemetry configuration.
- E.RESTCONF provides a YANG-based data model for streaming telemetry.
Why A: YANG models define the structure and constraints of telemetry data. Native models are vendor-specific, while OpenConfig models are standardized. IETF models are also standards-based but not vendor-specific. NETCONF uses YANG but is not a data model. RESTCONF is a protocol, not a model.
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.