Question Qos Rev b

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QUESTION 1 QoS stands for the following A. Quality of Signaling B. Quality of Service C. Quantum of Solace D. Quality of Signaling E. Quality of Signaling F. Quantity of Service G. Queuing or Scheduling Answer: B QUESTION 2 In which order the following actions are executed for a packet transferred through a router? A. Scheduling, Queuing, Marking, Classification B. Classification, Marking, Queuing, Scheduling C. Classification, Scheduling, Marking, Queuing D. Queuing, Marking, Classification, Scheduling Answer: B With regard to Ethernet media access methods, which of the following are true? (Choose all that apply.) A. A device waits for an electronic signal before transmitting. B. A device listens and waits until the media is not busy before transmitting. C. All devices on an Ethernet segment see data that passes on the network medium. D. Only the sender and the receiver devices see data that passes on the network medium. E. Ethernet networks allow you to configured devises with higher transmission priority. Answer: BC Section: (none) Explanation/Reference:

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IP QoS

Transcript of Question Qos Rev b

Page 1: Question Qos Rev b

QUESTION 1

QoS stands for the following

A. Quality of SignalingB. Quality of ServiceC. Quantum of SolaceD. Quality of SignalingE. Quality of SignalingF. Quantity of ServiceG. Queuing or Scheduling Answer: B

QUESTION 2

In which order the following actions are executed for a packet transferred through a router?

A. Scheduling, Queuing, Marking, ClassificationB. Classification, Marking, Queuing, Scheduling C. Classification, Scheduling, Marking, Queuing D. Queuing, Marking, Classification, Scheduling

Answer: B

With regard to Ethernet media access methods, which of the following are true? (Choose all that apply.)A. A device waits for an electronic signal before transmitting.B. A device listens and waits until the media is not busy before transmitting.C. All devices on an Ethernet segment see data that passes on the network medium.D. Only the sender and the receiver devices see data that passes on the network medium.E. Ethernet networks allow you to configured devises with higher transmission priority.

Answer: BCSection: (none)Explanation/Reference:Explanation:Ethernet uses the CSMA/CD access method.CSMA/CD logic helps prevent collisions and also defines how to act when a collision does occur. TheCSMA/CD algorithm words like this:1. A device with a frame to send listens until the Ethernet is not busy.2. When the Ethernet is not busy, the sender begins sending the frame.3. The sender listens to make sure that no collision occurred.4. Once the senders hear the collision, they each send a jamming signal, to ensure that all stationsrecognize the collision.5. After the jamming is complete, each sender randomizes a timer and waits that long.

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6 When each timer expires, the process starts over with Step 1. So, all devices on the Ethernet need to useCSMA/CD to avoid collisions and to recover when inadvertent collisions occur.

QUESTION 3

Which two QoS fields are NOT used to classify packets in a router? (Choose two)

A. EXPB. TTL C. IP precedence fieldD. ECNE. PCPF. PHB field

Answer: B, F

EXP (Experimental) is class value in MPLS header.TTL – Time to live.IP Precedence filed is used 3 MSB bit in TOS to classify the message.ECN (Explicit Congestion Notification) is used to signal to the source that there’s congestion in the networkPCP ( Priority Code Point)- is class value in Ethernet header.

PHB field: PHB’s are globally defined parameters that instruct a networknode (usually a router) on what action to perform on packets traversing it.

QUESTION 4

Which ones are Transport protocols?

A. SCTPB. ICMPC. ARPD. UDPE. SNMPF. TCP

Answer: A, D, F

QUESTION 5The following output was displayed on a TestKing device:While troubleshooting the installation of a new TestKing LAN device, the command output shown above wasissued. What is the meaning of the output "MTU 1500 bytes" shown above?A. The maximum number of bytes that can transverse this interface per second is 1500B. The maximum segment size that can transverse this interface is 1500 bytesC. The maximum packet size that can transverse this interface is 1500 bytesD. The maximum frame size that can transverse this interface is 1500 bytes

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E. None of the other alternatives apply

Answer: CSection: (none)Explanation/Reference:Explanation:Maximum transmission unit (MTU) defines the largest size of packets that an interface can transmit without the need to fragment. IP packets larger than the MTU must go through IP fragmentation procedures.

QUESTION 6

Put in correct order the QoS Classes from the higher to the lower priority?

A. EF, AF, BE, NCB. DF, AF, NC, EFC. NC, EF, AF, BED. BE, DF, AF, EF

Answer: C

NC : Network control is highest traffic type.It is used by router (ICMP,routing update) EF : Expedited Forwarding is  allow to provide priority values to different data applications. This QoS provide low latency , low loss and jitter.It is used for VOIP.AF : Assured forwarding allows the operator to provide assurance of delivery as long as the traffic does not exceed some subscribed rate. Traffic that exceeds the subscription rate faces a higher probability of being dropped if congestion occurBE: Best effort :End to end signaling

QUESTION 7

Which Application Layer protocols remain unchanged in the way they interwork with both IPv4 and IPv6? (Chose two) A. DNS B. Dual stack protocolsC. SNMP D. Teredo

Answer: A, C

QUESTION 8

An administrator attempts a traceroute but receives a "Destination Unreachable" message. Which protocol is responsible for that message?

A. RARPB. RUDPC. ICMPD. SNMP

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Answer: C

QUESTION 9

If an ethernet port on a router was assigned an IP address of 172.16.112.1/20, what is the maximum number of hosts allowed on this subnet?

A. 8190B. 4096C. 4094D. 2046E. 8190

Answer: C

Explanation/Reference:Since a /20 equates to 12 bits used for the subnet mask, 4094 hosts can be uniquely addressed.

QUESTION 10

First Generation IP networks were based on best effort approach

A. TrueB. False

Answer: A

QUESTION 11

A port has been configured with PWFQ scheduler for 4 queues and a maximum rate of 4 Mbps.Queue 0 has been configured with a priority 0 and a weight of 50.Queue 1 has been configured with priority 1 and weight 50.Queue 3 and 4 both have a priority of 2 but weights of 30 and 70 respectively.

At this given moment port receives the following traffic pattern:

No traffic for queue 0.1 Mb of traffic for queue 1.3 Mb for queue 3.2.5 Mb for queue 4.How much traffic will be transmitted from Queue 4

A. 2.5 MbB. 3 Mb

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C. 0.7 MbD. 2.1 Mb

Answer: D

QUESTION 12

If using MPLS then the QoS information is stored in which field in the MPLS header?

A. PCPB. EXPC. TTLD. ECN

Answer: B

QUESTION 13

Which of the following DiffServ functions are done on the egress of a DS domain?

A. SchedulingB. MarkingC. ClassificationD. QueuingE. PolicingF. Congestion Avoidance

Answer: A , D , F

QUESTION 14

Which of the following DiffServ functions are done on the ingress of a DS domain?

A. SchedulingB. MarkingC. ClassificationD. QueuingE. PolicingF. Congestion Avoidance

Answer: B , C , E

QUESTION 15

Even if there is plenty of bandwidth available, which of the following might still cause problems in the network?

A. DelayB. JitterC. Loss

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D. Throughput

Answer: B

Question 16

A port has been configured with PWFQ scheduler for 4 queues and a maximum rate of 4 Mbps.Queue 0 has been configured with a priority 0 and a weight of 50.Queue 1 has been configured with priority 1 and weight 50.Queue 3 and 4 both have a priority of 2 but weights of 30 and 70 respectively.

At this given moment port receives the following traffic pattern:

No traffic for queue 0.1 Mb of traffic for queue 1.3 Mb for queue 3.2.5 Mb for queue 4.How much traffic will be transmitted from Queue 1

A. .5 MbB. .3 MbC. 0 MbD. 1 Mb

Answer: D

Question 17

A port has been configured with PWFQ scheduler for 4 queues and a maximum rate of 4 Mbps.Queue 0 has been configured with a priority 0 and a weight of 50.Queue 1 has been configured with priority 1 and weight 50.Queue 3 and 4 both have a priority of 2 but weights of 60 and 40 respectively.

At this given moment port receives the following traffic pattern:

No traffic for queue 0.1 Mb of traffic for queue 1.3 Mb for queue 3.2 Mb for queue 4.How much traffic will be transmitted from Queue 4

A. .5 MbB. 3 MbC. 1 Mb

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D. 2 Mb

Answer: C

Question 18Which subnet mask will allow 66 hosts in a network?

A. /25B. /26C. /27D. /28

Answer: A

Question 19

Mark the which statement is applicable of corresponding model

a. The path of customer packets are going to travel over is established before the packets are forwarded.b. Each router takes independent decisions based on packer header information.c. The DSCP bits are used to provide the QoS by differentiating class of traffic d. Qos is applied by adding precedence value in ToS field on a per call basis.e- Customer gets service on best approach basis.

X1-intserv X2-Diffserv

A. a-X1,b-X2,c-X2,e-X1B. a-X2,b-X2,c-X1,d-X2C. a-X1,b-X2,c-X2,e-X2D. a-X1,b-X2,c-X1,d-X2

Answer: A

Question 20

What is the principle reason to use a private IP address on an internal network?

A. Subnet strategy for private companies.B. Manage and scale the growth of the internal network.C. Conserve public IP addresses so that we do not run out of them.D. Allow access reserved to the devices.

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Answer: C