"Do I Know This Already?" Quiz

The purpose of the "Do I Know This Already?" quiz is to help you decide whether you really need to read the entire chapter. If you already intend to read the entire chapter, you do not necessarily need to answer these questions now.

The 10-question quiz, derived from the major sections in the "Foundation Topics" portion of the chapter, helps you determine how to spend your limited study time.

Table 1-1 outlines the major topics discussed in this chapter and the "Do I Know This Already?" quiz questions that correspond to those topics.

Table 1-1. "Do I Know This Already?" Foundation Topics Section-to-Question Mapping

Foundation Topics Section Covering These Questions	Questions	Score
QoS: Tuning Bandwidth, Delay, Jitter, and Loss	15
Traffic Characteristics of Voice, Video, and Data	68
Planning and Implementing QoS Policies	910

You can find the answers to the "Do I Know This Already?" quiz in Appendix A, "Answers to the 'Do I Know This Already?' Quizzes and Q&A Sections." The suggested choices for your next step are as follows:

• 8 or less overall score Read the entire chapter. This includes the "Foundation Topics," the "Foundation Summary," and the "Q&A" section.
  
  
• 9 or 10 overall score If you want more review on these topics, skip to the "Foundation Summary" section and then go to the "Q&A" section. Otherwise, proceed to the next chapter.
  
  

QoS: Tuning Bandwidth, Delay, Jitter, and Loss Questions

1.	Which of the following are not traffic characteristics that can be affected by QoS tools? Bandwidth Delay Reliability MTU
2.	Which of the following characterize problems that could occur with voice traffic when QoS is not applied in a network? Voice sounds choppy. Calls are disconnected. Voice call requires more bandwidth as lost packets are retransmitted. VoIP broadcasts increase as Queuing delay increases, causing delay and caller interaction problems.
3.	What does a router base its opinion of how much bandwidth is available to a queuing tool on a serial interface? The automatically-sensed physical transmission rate on the serial interface. The clock rate command is required before a queuing tool knows how much bandwidth is available. The bandwidth command is required before a queuing tool knows how much bandwidth is available. Defaults to T1 speed, unless the clock rate command has been configured. Defaults to T1 speed, unless the bandwidth command has been configured.
4.	Which of the following components of delay varies based on the varying sizes of packets sent through the network? Propagation delay Serialization delay Codec delay Queuing delay
5.	Which of the following is the most likely reason for packet loss in a typical network? Bit errors during transmission Jitter thresholds being exceeded Tail drops when queues fill TCP flush messages as a result of Round-Trip Times varying wildly

Traffic Characteristics of Voice, Video, and Data Questions

6.	Ignoring Layer 2 overhead, how much bandwidth is required for a VoIP call using a G.729 coded? (Link: Voice Bandwidth Considerations) 8 kbps 16 kbps 24 kbps 32 kbps 64 kbps 80 kbps
7.	Which of the following are components of delay for a VoIP call, but not for a data application? Packetization delay Queuing delay Serialization delay Filling the De-jitter buffer
8.	Which of the following are true statements of both Voice and Video conferencing traffic? Traffic is isochronous All packets in a single call or conference are a of single size Sensitive to delay Sensitive to jitter

Planning and Implementing QoS Policies

9.	Which of the following are not one of the major planning steps when implementing QoS Policies? Divide traffic into classes Define QoS policies for each class Mark traffic as close to the source as possible Identify traffic and its requirements
10.	When planning QoS policies, which of the following are important actions to take when trying to identify traffic and its requirements? Network audit Business audit Testing by changing current QoS settings to use all defaults Enabling shaping, and continually reducing the shaping rate, until users start complaining