Practice QoS Questions Now
Start a timed practice session focusing on Quality of Service topics from the CCNA question bank.
Start CCNA Practice Quiz →CCNA QoS Question Bank (2 Questions)
Browse all 2 practice questions covering Quality of Service for the CCNA certification exam. Each question includes the full answer and a detailed explanation to help you understand the concepts.
- Question 1Network Fundamentals
What DSCP value is typically used for voice traffic?
Show Answer & Explanation
Correct Answer: BExplanation:Voice traffic uses DSCP EF (46) = Expedited Forwarding, ensuring priority treatment. Voice signaling uses DSCP CS3 (24) or AF31 (26). Video conferencing uses AF41 (34). Best Effort is DSCP 0. These markings map to per-hop behaviors (PHB) for QoS enforcement.
- Question 2IP Services
A network engineer configures QoS on a router. Which DSCP value is typically assigned to voice (EF — Expedited Forwarding) traffic?
Show Answer & Explanation
Correct Answer: CExplanation:DSCP 46 corresponds to Expedited Forwarding (EF), which is used for voice traffic requiring low latency, low jitter, and low packet loss. DSCP 0 is best effort. AF31 (DSCP 26) is typically used for streaming video or multimedia. CS6 (DSCP 48) is typically used for network control traffic.
Key QoS Concepts for CCNA
CCNA QoS Exam Tips
Quality of Service questions in CCNA are typically scenario-based. Focus on service-level decision making aligned to official exam objectives. Priority concepts: qos, dscp, cos, marking, queuing, policing.
What CCNA Expects
- Anchor your answer in select the most practical, secure, and scalable answer for the stated scenario.
- QoS scenarios for CCNA are frequently mapped to Domain 4 (10%), so read the objective carefully before picking controls or architecture.
- Expect multi-service scenarios where QoS interacts with IAM, networking, storage, or observability patterns rather than appearing as an isolated service question.
- When two options are both technically valid, prefer the choice that best aligns with the exam's operational scope (Associate) and managed-service best practices.
High-Value QoS Concepts
- Know the core QoS building blocks cold: qos, dscp, cos, marking.
- Review the edge-case features and limits for queuing, policing; these details are commonly used to differentiate answer choices.
- Practice service-integration reasoning: how QoS pairs with IP Services, WAN, Network Fundamentals in real deployment patterns.
- For CCNA, explain why the chosen QoS design meets reliability, security, and cost expectations better than the alternatives.
Common CCNA Traps
- Watch for answers that partially solve the requirement but miss operational constraints.
- Questions in IP Services often include distractors that look correct for QoS but violate least-privilege, durability, or availability requirements.
- Avoid picking options purely by feature name; validate data path, failure handling, and governance impact before answering.
- If the prompt hints at automation or repeatability, eliminate manual-only operational answers first.
Fast Review Checklist
- Can you compare at least two QoS implementation paths and justify which one best fits the scenario?
- Can you map the chosen answer back to IP Services (10%) outcomes for CCNA?
- Can you explain security and access boundaries for QoS without relying on default-open assumptions?
- Can you describe how QoS integrates with IP Services and WAN during failure, scaling, and monitoring events?