Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
Which traffic type is typically most sensitive to delay and jitter and is commonly prioritized with QoS?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
A
Best answer
Voice traffic
Correct. Voice is the classic latency-sensitive traffic class.
B
Distractor review
Bulk backup traffic
Backups are usually throughput-sensitive, not real-time sensitive.
C
Distractor review
Email attachments
Email is less sensitive to short delay variation.
D
Distractor review
Operating system updates
Updates are not usually treated as real-time traffic.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A common exam trap is assuming that all traffic types require equal QoS prioritization. Candidates might incorrectly select bulk backup traffic or email attachments because they involve large data transfers, but these are not sensitive to delay or jitter. The trap lies in confusing throughput sensitivity with latency sensitivity. Voice traffic demands low latency and minimal jitter to maintain call quality, which is why it is prioritized. Misunderstanding this distinction can lead to choosing incorrect answers that focus on volume rather than real-time sensitivity.
Technical deep dive
How to think about this question
Quality of Service (QoS) is a set of techniques used in Cisco networks to manage bandwidth, delay, jitter, and packet loss for different types of traffic. Voice traffic, such as VoIP, is highly sensitive to delay and jitter because even small variations can cause noticeable degradation in call quality, including choppiness or dropped audio. Unlike bulk data transfers, voice packets must be delivered in a timely and consistent manner to maintain the integrity of the conversation. Cisco devices use QoS policies to classify and prioritize traffic based on its sensitivity to network conditions. Voice traffic is typically marked with higher priority using mechanisms like Class of Service (CoS) or Differentiated Services Code Point (DSCP) values. This ensures that voice packets are forwarded ahead of less sensitive traffic like backups or email, which can tolerate delays without impacting user experience. The decision process involves identifying traffic types and applying appropriate queuing and scheduling techniques to minimize latency and jitter for voice. A common confusion in the CCNA exam is mistaking throughput-sensitive traffic for delay-sensitive traffic. Bulk backup traffic and operating system updates require high throughput but are not sensitive to delay or jitter, so they are not prioritized by QoS. Voice traffic’s real-time nature means it must be prioritized to avoid quality issues. Practically, network engineers configure QoS policies on Cisco routers and switches to ensure voice traffic receives expedited forwarding, preventing degradation even in congested networks.
KKey Concepts to Remember
- Voice traffic is highly sensitive to delay and jitter, requiring prioritization in QoS policies to maintain call quality.
- QoS mechanisms in Cisco networks classify and mark voice packets to ensure low latency and minimal jitter during transmission.
- Bulk backup traffic demands high throughput but is not sensitive to delay or jitter, so it is not prioritized by QoS.
- Email attachments and operating system updates tolerate delay and jitter, making them lower priority for QoS treatment.
- Cisco QoS uses classification, marking, queuing, and scheduling to differentiate real-time voice traffic from less time-sensitive data.
- Prioritizing voice traffic prevents call quality degradation caused by network congestion and variable delay.
- Understanding traffic sensitivity helps correctly apply QoS policies and avoid common exam mistakes related to traffic prioritization.
- QoS policies on Cisco devices use DSCP or CoS values to identify and expedite voice traffic over other types.
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.
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More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
Question 1
A router learns the same prefix from both OSPF and EIGRP. Which route is installed by default?
Question 2
A router shows this output: R1#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 10.1.1.2 1 FULL/DR 00:00:34 192.168.12.2 GigabitEthernet0/0 10.1.1.3 1 2WAY/DROTHER 00:00:39 192.168.12.3 GigabitEthernet0/0 Which statement is correct?
Question 3
What is the OSPF metric called?
Question 4
A non-root switch has two uplinks toward the root bridge. One path has a lower total STP cost than the other. What role will the lower-cost uplink have?
Question 5
A router interface applies this ACL inbound: 10 deny tcp any any eq 80 20 permit ip any any A user reports that web browsing to a server by IP address fails, but ping works. Which statement best explains the behavior?
Question 6
A router learns route 198.51.100.0/24 from OSPF with AD 110 and also has a static route to the same prefix configured with AD 150. Which route is installed?
FAQ
Questions learners often ask
What does this 200-301 question test?
Voice traffic is highly sensitive to delay and jitter, requiring prioritization in QoS policies to maintain call quality.
What is the correct answer to this question?
The correct answer is: Voice traffic — Voice traffic is highly sensitive to delay, jitter, and packet loss, so it is commonly prioritized in QoS policies.
What should I do if I get this 200-301 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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