642-642 by Cisco Valid Free Exam Practice Test

Question 1

Refer to the exhibit. A typical configuration involving an IP phone with an attached PC is shown. According to QoS recommendations, at which demarcation line (shown as dotted lines) would the trust boundary normally exist?

A. D B. B C. A D. C

Correct Answer: B

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Question 2

DRAG DROP

Correct Answer:

Question 3

According to the best practices, in a service provider network, which statement is true as related to the QoS policy that should be implemented on the inbound provider (P) to provider (P) router link?

A. Class-based marking should be implemented because it will be needed for the class-based queuing that will be used on the P router output. B. Traffic policing should be implemented to rate-limit the ingress traffic into the P router. C. Because traffic should have already been policed and marked on the upstream ingress PE router, no input QoS policy is needed on the P to P link. D. In the DiffServ model, all ingress and egress QoS processing are done at the network edge (for example, PE router), so no input or output QoS policy will be needed on the P to P link.

Correct Answer: C

Question 4

To determine the bandwidth requirement for each VoIP call, not including Layer 2 overhead, how much bandwidth per call should be added to account for the voice signaling traffic?

A. 40 bps B. 480 bps C. 20 bps D. 640 bps E. 240 bps F. 150 bps

Correct Answer: F

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Question 5

What will be the peak shape rate based on the configuration that follows?
policy-map setpeak
class all-traffic
shape peak 32000

A. 80000 bps B. 32000 bps C. 96000 bps D. 48000 bps E. 16000 bps F. 64000 bps

Correct Answer: F

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Question 6

When LLQ is being configured, which IOS command is used to limit the traffic rate on the priority queue even when the other class queues are not congested?

A. police B. priority C. queue-limit D. bandwidth E. hold-queue

Correct Answer: A

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Question 7

According to the best practices, which statement is true as related to the QoS policy that should be implemented on the outbound provider (P) to provider (P) router link in a service provider network that is supporting both VoIP and data?

A. CBWFQ and CB-RTP header compression should be implemented on the P router egress to ensure minimum latency for VoIP traffic. B. CBWFQ and CB-WRED should be implemented on the P router egress to provide a maximum bandwidth guarantee for the VoIP traffic. C. LLQ and CB-WRED should be implemented on the P router egress to support both VoIP and data traffic. D. In the DiffServ model, ingress and egress QoS mechanisms are only required on the provider edge (PE) routers, so no QoS policy is needed on the P to P link.

Correct Answer: C

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Question 8

This policy-map is applied to a 128-kbps serial interface in the output direction. Which set of additional commands within this policy-map will improve the link efficiency on the serial interface?
policy-map test
class voice
priority 25
class telnet
bandwidth remaining percent 20
class ftp
bandwidth remaining percent 30

A. class telnet
fair-queue B. class ftp
compression header ip C. class telnet
compression header ip tcp D. class ftp
fair-queue E. class voice
no priority 25
bandwidth percent remaining 25 F. class voice
compression header ip tcp

Correct Answer: C

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Question 9

DRAG DROP
Drop

Correct Answer:

Cisco Quality of Service (QoS) - 642-642 Exam Practice Test