- A
A: Transport layer
The Transport layer manages end-to-end connections, flow control, and error recovery.
- B
B: Network layer
Why wrong: The Network layer handles routing and logical addressing, not flow control or error recovery.
- C
C: Data Link layer
Why wrong: The Data Link layer deals with node-to-node delivery on the same link, but end-to-end flow control is at the Transport layer.
- D
D: Session layer
Why wrong: The Session layer manages sessions between applications, not flow control or error recovery.
Question 135 of 520
N10-009 Networking Concepts Practice Question
This N10-009 practice question tests your understanding of networking concepts. 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.
At which layer of the OSI model does a device provide flow control, error detection, and recovery for end-to-end communication?
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
✓
A: Transport layer
The Transport layer (Layer 4) is responsible for end-to-end communication between source and destination hosts. It provides flow control (e.g., TCP's sliding window mechanism), error detection (via checksums in TCP and UDP headers), and recovery (through TCP retransmission of lost segments). These functions ensure reliable data delivery across the network, distinguishing it from lower layers that handle hop-by-hop or link-local tasks.
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.
- ✓
A: Transport layer
Why this is correct
The Transport layer manages end-to-end connections, flow control, and error recovery.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
B: Network layer
Why it's wrong here
The Network layer handles routing and logical addressing, not flow control or error recovery.
When this WOULD be correct
A question asking 'At which layer does a device provide logical addressing and routing between networks?' would have the Network layer as the correct answer.
- ✗
C: Data Link layer
Why it's wrong here
The Data Link layer deals with node-to-node delivery on the same link, but end-to-end flow control is at the Transport layer.
When this WOULD be correct
A question asking: 'At which layer of the OSI model does a device provide flow control, error detection, and recovery for communication between two directly connected nodes?' would make the Data Link layer correct.
- ✗
D: Session layer
Why it's wrong here
The Session layer manages sessions between applications, not flow control or error recovery.
When this WOULD be correct
A question asking: 'At which OSI layer does a device manage dialog control, session establishment, and checkpointing?' would make the Session layer the correct answer.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The N10-009 exam frequently reuses these exact scenarios with slightly different constraints.
✓A: Transport layerCorrect answer▾
Why this is correct
The Transport layer manages end-to-end connections, flow control, and error recovery.
✗B: Network layerWrong answer — click to see why▾
Why this is wrong here
The Network layer (Layer 3) handles routing and logical addressing, but flow control, error detection, and recovery for end-to-end communication are functions of the Transport layer (Layer 4).
★ When this WOULD be the correct answer
A question asking 'At which layer does a device provide logical addressing and routing between networks?' would have the Network layer as the correct answer.
Why candidates choose this
Candidates may confuse the Network layer's end-to-end delivery of packets with the Transport layer's end-to-end communication services, or they may associate error detection with IP checksums.
✗C: Data Link layerWrong answer — click to see why▾
Why this is wrong here
The Data Link layer provides flow control, error detection, and recovery only for direct node-to-node links, not for end-to-end communication across multiple network segments.
★ When this WOULD be the correct answer
A question asking: 'At which layer of the OSI model does a device provide flow control, error detection, and recovery for communication between two directly connected nodes?' would make the Data Link layer correct.
Why candidates choose this
Candidates may confuse the Data Link layer's local error control with the Transport layer's end-to-end responsibilities, especially since both layers perform similar functions but at different scopes.
✗D: Session layerWrong answer — click to see why▾
Why this is wrong here
The Session layer (Layer 5) manages sessions, dialog control, and synchronization, but does not provide flow control, error detection, or recovery for end-to-end communication; those functions belong to the Transport layer.
★ When this WOULD be the correct answer
A question asking: 'At which OSI layer does a device manage dialog control, session establishment, and checkpointing?' would make the Session layer the correct answer.
Why candidates choose this
Candidates may confuse session management with end-to-end communication services, or incorrectly associate 'recovery' with session checkpointing rather than transport-layer retransmission.
Analysis generated from the official N10-009blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Common exam traps
Common exam trap: answer the scenario, not the keyword
The N10-009 exam often tests the distinction between hop-by-hop (Data Link) and end-to-end (Transport) responsibilities, tricking candidates into confusing link-layer error detection (e.g., Ethernet CRC) with end-to-end recovery, which is exclusively a Transport layer function.
Detailed technical explanation
How to think about this question
TCP at the Transport layer uses sequence numbers and acknowledgment (ACK) segments to implement flow control via the receiver's advertised window, and error recovery through retransmission of unacknowledged segments. In contrast, UDP at the same layer provides only minimal error detection (checksum) without recovery, highlighting that flow control and recovery are optional but characteristic of connection-oriented protocols. Real-world scenarios like video streaming may use UDP to avoid retransmission delays, while file transfers rely on TCP's robust recovery.
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 practitioner preparing for the N10-009 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
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.
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Networking Concepts — study guide chapter
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FAQ
Questions learners often ask
What does this N10-009 question test?
Networking Concepts — This question tests Networking Concepts — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: A: Transport layer — The Transport layer (Layer 4) is responsible for end-to-end communication between source and destination hosts. It provides flow control (e.g., TCP's sliding window mechanism), error detection (via checksums in TCP and UDP headers), and recovery (through TCP retransmission of lost segments). These functions ensure reliable data delivery across the network, distinguishing it from lower layers that handle hop-by-hop or link-local tasks.
What should I do if I get this N10-009 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 →
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Last reviewed: Jun 11, 2026
This N10-009 practice question is part of Courseiva's free CompTIA 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 N10-009 exam.
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