1. Implementing Quality of Service (QoS)
Module 1 Lesson 1 Review

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Question 1
What is the best method for solving the bandwidth shortage on a link? a. Upgrade the link b. Use an advanced queuing strategy c. Compress payloads d. Compress headers
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Question 1 - Answer
What is the best method for solving the bandwidth shortage on a link? a. Upgrade the link b. Use an advanced queuing strategy c. Compress payloads d. Compress headers
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Question 2
Match the type of delay with the correct definition:
Processing Delay
Queuing Delay
Propagation Delay
Serialization Delay
Packetization Delay
Time from input interface to output
Time in output queue
Time spent on wire
Time to put bits on wire
Time to convert data to packets
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Question 2 - Answer
Match the type of delay with the correct definition:
Serialization Delay
Packetization Delay
Queuing Delay
Processing Delay
Propagation Delay
Time from input interface to output
Time in output queue
Time spent on wire
Time to put bits on wire
Time to convert data to packets
a b c. 2 d. 1 e. 3
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Question 3
What is the most common reason for packet loss in a network? a. Tail drop b. Ignore c. Overrun d. Frame Error
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Question 3 - Answer
What is the most common reason for packet loss in a network? a. Tail drop b. Ignore c. Overrun d. Frame Error
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Question 4
Some service providers overprovision their bandwidth to avoid the configuration of complex QoS mechanisms. Identify a drawback of this design philosophy.
The customer edge (CE) router must implement multiple QoS mechanisms.
The provider edge (PE) router must implement multiple QoS mechanisms.
The unpredictability of traffic resulting from the lack QoS mechanisms in the service provider’s core results in a higher probability of network congestion.
The service provider’s recurring expenses are higher for an overprovisioned network as opposed to a QoS-enabled network.
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Question 4 - Answer
Some service providers overprovision their bandwidth to avoid the configuration of complex QoS mechanisms. Identify a drawback of this design philosophy.
The customer edge (CE) router must implement multiple QoS mechanisms.
The provider edge (PE) router must implement multiple QoS mechanisms.
The unpredictability of traffic resulting from the lack QoS mechanisms in the service provider’s core results in a higher probability of network congestion.
The service provider’s recurring expenses are higher for an overprovisioned network as opposed to a QoS-enabled network.
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Question 5
Which of the following types of delay is considered to be a variable delay?
serialization delay
queuing delay
processing delay
propagation delay
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Question 5 - Answer
Which of the following types of delay is considered to be a variable delay?
serialization delay
queuing delay
processing delay
propagation delay
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Question 6
The three primary quality issues that QoS mechanisms address are: (1) Packet Loss, (2) Jitter, and (3) Delay. Which two of the following mechanisms can be used to reduce packet loss for your higher priority traffic? (Choose 2)
Increase link speed
Use WRED
Decrease the size of the dejitter buffer
Police all flows
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Question 6 - Answer
The three primary quality issues that QoS mechanisms address are: (1) Packet Loss, (2) Jitter, and (3) Delay. Which two of the following mechanisms can be used to reduce packet loss for your higher priority traffic? (Choose 2)
Increase link speed
Use WRED
Decrease the size of the dejitter buffer
Police all flows
Copyright © 2010 Internetwork Expert, Inc