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QUESTION 51
Which 3 options may be used on Cisco Catalyst switches for classifying IP Packets? (Choose 3)
A. 802.1Q
B. ISL CoS
C. Priority
D. MED
E. 802.1E

Correct Answer: ABC Section: (none) Explanation
Explanation/Reference:
QUESTION 52
Which three QoS markers can be set using class-based marking? (Choose three.)
A. discard-threshold
B. qos-group
C. mpls exp bits
D. cos
E. becn
F. fecn

Correct Answer: BCD Section: (none) Explanation
Explanation/Reference:
Explanation: Class-based Marking supports following markers: 1) IP precedence 2) DSCP 3) QoS group 4) MPLS expertimental bits 5) ATM CLP bit 6) Frame Relay DE bit 7) 802.1Q/ISL cos/priority Reference: IP QoS Introduction p.64
QUESTION 53
Based on Cisco’s best practice recommendation, where should classification and marking be applied in a network?
A. in the core
B. at the access layer
C. at the distribution layer
D. as close to the source as possible
E. as close to the desalination as possible

Correct Answer: D Section: (none) Explanation
Explanation/Reference:
Explanation:
Good QoS design calls for the marking of packets close to the source of the packet.
Reference: DQOS Exam Certification Guide p.849

QUESTION 54
You work as a network administrator at Certkiller .com. You are required to implement prioritizing,
protection, and isolation of traffic based on marking.
Which mechanism should you deploy?

A. classification and marking
B. congestion management
C. congestion avoidance
D. metering
E. policing
F. shaping

Correct Answer: B Section: (none) Explanation
Explanation/Reference:
Explanation:
Congestion management is needed here. It deals with prioritization, protection and isolation of traffic. All
this mechanisms are used for congestion avoidance.

QUESTION 55
When RED is used as a dropping mechanism to avoid a full queue, which problem is exhibited if the minimum threshold and the maximum threshold are too close in size?
A. Queues fill and tail-drop drops packets.
B. The mark probability denominator is set to zero.
C. The default average queue size is rest to 512 packets.
D. TCP global synchronization can occur.

Correct Answer: D Section: (none) Explanation
Explanation/Reference:
Explanation: When congestion occurs, dropping affect most of the TCP sessions, which simultaneously back-off and then restart again. This causes inefficient link utilization at the congestion point (TCP global synchronization). Reference: Introduction to IP QoS p.5-4
QUESTION 56
Which Cisco IOS feature must be enabled before configuring class-based marking?
A. FEC
B. netflow
C. CEF
D. QBBP
E. Tcp small-server
F. ip classless

Correct Answer: C Section: (none) Explanation
Explanation/Reference:
QUESTION 57
When queue on the Catalyst 2950 can be configured as the expedite queue?
A. queue 1
B. queue 2
C. queue 3
D. queue 4

Correct Answer: D Section: (none) Explanation
Explanation/Reference:
QUESTION 58
DRAG DROP

+
A.
B.
C.
D.

Correct Answer: Section: (none) Explanation
Explanation/Reference:

QUESTION 59
Which three prerequisites must be met before using AutoQoS? (Choose three.)
A. Cisco Express forwarding (CEF) must be enabled at the interface or ATM PVC.
B. Preconfigured policy maps must exist for AutoQoS to operate correctly.
C. AutoQoS cannot be configured if a service policy is attached to an interface.
D. The no ip address command is required for all interfaces or subinterfaces with link speeds less than 768 kbps.
E. On all interfaces or subinterfaces, the correct bandwidth should be configured with the bandwidth command.

Correct Answer: ACE Section: (none) Explanation
Explanation/Reference:
QUESTION 60
What are the three primary challenges when dealing with a converged network that QoS can help solve? (Choose three.)
A. delay
B. packet loss
C. server congestion
D. lack of bandwidth
E. port overutilization

Correct Answer: ABD Section: (none) Explanation
Explanation/Reference:
Explanation:
QoS can solve following issues:

1) Lack of bandwidth – multiple flows are contesting for a limited amount of bandwidth 2) Too much delay – packets have to traverse many network devices and links that add up to the overall delay 3) Variable delay – sometimes there is a lot of other traffic which results in more delay 4) Drops – packets have to be dropped when a link is congested
QUESTION 61
Configuration: Policy-map shape-cbwfq Class interactive Shape average 256000 Shape adaptive 128000 Bandwidth 128 Based on the configuration, which two statements are true? (Choose two.)
A. The interactive traffic class will have a minimum bandwidth guarantee of 256 kbps.
B. The interactive traffic class will have a maximum bandwidth guarantee of 256 kbps.
C. If the interactive traffic class exceeds an average rate of 256 kbps. The traffic rate will be throttled down to 128 kbps.
D. This configuration allows class-based traffic shaping to lower the traffic rate in response to the BECN bit.
E. The interactive traffic class will have a min-rate (min-cir) of 128 kbps.

Correct Answer: CE Section: (none) Explanation
Explanation/Reference:
QUESTION 62
Given the router configuration: interface Ethernet 0 ip address 10.1.1.1 255.255.255.0 ip policy-map set-prec ! route-map set-prec permit 10 match ip address 101 set ip precedence 1 ! route-map set-prec permit 20 set ip precedence 0 ! access-list 101 permit tcp any any eq telnet ! According the configuration illustrated above which of the following statements is valid?
A. All telnet packets from the Ethernet 0 interface are marked with IP precedence 0.
B. All packets sourced locally by the router that goes out on the Ethernet 0 interface are marked with IP precedence 1.
C. All non-telnet traffic from the Ethernet 0 interface is marked with IP precedence 0.
D. All telnet packets sourced locally by the router that goes out on the Ethernet 0 interface are marked with IP precedence 1.

Correct Answer: C Section: (none) Explanation
Explanation/Reference:
Explanation: A route map is created with three statements, one for each application: The first statement uses an access list to identify corporate web traffic (destination port 80). IP precedence 1 is applied to these packets. The second statement uses another access list to identify outbound telnet sessions. IP precedence 2 is applied to these packets. The last statement sets IP precedence 0 to all other packets. Source: Cisco IP QoS Classification and Marking, Page 2-19

QUESTION 63
What is the result of properly configured Priority Queuing on Cisco IOS routers?
A. A starvation condition can occur where lower priority queues are never serviced.
B. Priority Queuing overhead can be too taxing on slow WAN links and might result in buffer exhaustion.
C. By default, unclassified packets are placed into the high priority output queue, which can affect high priority traffic.
D. The high priority queue has a default queue limit of 80, that can result in excessive packet loss.

Correct Answer: A Section: (none) Explanation
Explanation/Reference:
Incorrect:
C. By default, unclassified packets are placed into the normal priority output queue. D. The high priority queue has a default queue limit of 20.
Explanation: As mentioned previously, Priority Queuing suffers from the same drawbacks as FIFO queuing, except it is localized to four classes. Each class can experience starvation, delay and jitter if one or more flows in the class cause congestion. Furthermore, one higher-priority queue can cause all other queues to starve if it is congested. Priority Queuing requires manual configuration of classification. The main benefit of PQ is that it enables the user to create a class that is used for applications that require low delay (high queue). Source: Cisco Queuing Mechanisms, Page 3-24

QUESTION 64
What is the default match strategy for a class map?
A. match none
B. match any
C. match some
D. match all
E. match one

Correct Answer: D Section: (none) Explanation
Explanation/Reference:
Explanation:
There are two ways of processing conditions when there is more than one condition in a class map:
1) Match all – all conditions have to be met to bind a packet to the class
2) Match any – at least one condition has to be met to bind the packet to the class The default match
strategy of class maps is “Match all”.
Reference: Introduction to IP QoS p.8-6

QUESTION 65
Which one of the following configurations provides a maximum bandwidth guarantee of 192 kbps for the real-time traffic class?
A. class real-time bandwidth 192
B. class real-time Priority 192
C. class real-time Shape peak 192000
D. class real-time Shape average 192000
E. class real-time police 192000 conform-action transmit exceed-action drop

Correct Answer: B Section: (none) Explanation
Explanation/Reference:
Explanation:
For real-time traffic class maximum bandwidth guarantee is configured using priority command.

QUESTION 66
The Tx Ring always uses which queuing method?
A. PQ
B. CQ
C. DRR
D. FIFO
E. WFQ
F. CBWFQ

Correct Answer: D Section: (none) Explanation
Explanation/Reference:
Explanation:
The following list summarizes the key points about TX Rings and TX Queues in relation to their effect on
queuing:
1) The TX Queue/TX Ring always performs FIFO scheduling, and cannot be changed.
2) The TX Queue/TX Ring uses a single queue, per interface.
3) IOS shortens the interface TX Queue/TX Ring automatically when an output queuing method is
configured.
4) The TX Ring/TX queue length can be configured to a different value.
Reference: DQOS Exam Certification Guide p.245

QUESTION 67
Modified Deficit Round Robin (MDRR) service algorithm is capable of supporting which of the following operating modes? (Choose all that apply.)
A. FIFO
B. weighted priority
C. strict priority
D. shared priority
E. alternate priority

Correct Answer: CE Section: (none) Explanation
Explanation/Reference:
Explanation:

DRR was the first implementation that was later improved by allowing one queue to be high priority. Source: Cisco Queuing Mechanisms, Page 3-120
QUESTION 68
Which two procedures are required to configure AutoQoS on a Cisco router? (choose two)
A. Enable CEF globally
B. Configure map-class for AF traffic
C. Configure service-class for voice
D. Set the clock rate on the interface
E. Set the bandwidth statement on the interface

Correct Answer: AE Section: (none) Explanation
Explanation/Reference:
Page 163, Cisco QOS Exam Certification Guide (IP Telephony Self-Study), 2nd Edition, http// www.ciscopress.com/title/1587201240
QUESTION 69
Which command is used to configure DSCP-based CB-WRED on an interface?
A. weighted-random dscp-based
B. random-queue dscp
C. random-detect dscp-based
D. weighted-queue dscp
Correct Answer: C Section: (none) Explanation

Explanation/Reference:
Page 500, IP Telephony Self-Study Cisco DQOS Exam Certification Guide, http//www.ciscopress.com/ title/1587200589
QUESTION 70
Within CBWFQ, what is the default dropping scheme used when a CBWFQ class queue reaches its configured queue limit?
A. WRR
B. tail drop
C. WRED
D. RED

Correct Answer: B Section: (none) Explanation
Explanation/Reference:
Reference: Page 273, IP Telephony Self-Study Cisco DQOS Exam Certification Guide, http// www.ciscopress.com/title/1587200589
QUESTION 71
Which queuing method solves the problems created by inaccuate round-robin byte counting?
A. PQ
B. DRR
C. FIFO
D. MWRR

Correct Answer: B Section: (none) Explanation
Explanation/Reference:
Explanation:
DRR can use Wighted Random Early Detection (WRED) within each class to prevent congestion within the
class.
The scheduling of DRR is similar to that of Custom Queuing, except it is more accurate. DRR remembers
the number of bytes it sent above the threshold in the previous roung (deficit).
Reference: Introduction to IP QoS p.3-123

QUESTION 72
Which of the following statements represents a disadvantage of FIFO queuing?
A. FIFO queuing produces excessive jitter.
B. FIFO queuing supports packets of queue size of 40 exclusively.
C. FIFO queuing can only support packet classification based upon traffic flows.
D. FIFOI queuing is only available on interfaces that operate at 2 Mbps or higher.

Correct Answer: A Section: (none) Explanation
Explanation/Reference:
Incorrect:
D: Disable WFQ to enable FIFO on interfaces that have less than 2Mbps of bandwidth
Explanation: FIFO queuing might be regarded as the fairest queuing mechanism but it has a long list of drawbacks: FIFO does not fairly allocate bandwidth among multiple flows. Some flows receive more bandwidth because they use larger packets or send more packets. FIFO is extremely unfair when an aggressive flow is contesting with a fragile flow. Aggressive flows send a large number of packets, many of which are dropped. Fragile flows send a modest amount of packets and most of them are dropped because the queue is always full due to the aggressive flow. This type of behavior is called starvation. Short or long bursts cause a FIFO queue to fill. Packets entering an almost full queue have to wait a long time before they can be transmitted. Another time, the queue might be empty causing packets of the same flow to experience almost no delay. Variation in delay is called jitter. In spite of all the drawbacks FIFO is still the most used queuing mechanism because of the following benefits: It is simple and fast. Most high-end routers with fast interfaces are not really challenged by the drawbacks mentioned earlier. Furthermore, routers are not capable of complex classification and scheduling when they have to process a large number of packets per second. FIFO is, therefore, the most suitable queuing mechanisms on these platforms. It is supported on all platforms. It is supported in all IOS versions. Source: Cisco Queuing Mechanisms, Page 3-12

QUESTION 73
The newly appointed Certkiller trainee technician wants to know what services are provided through Committed Access Rate (CAR). What will your reply be? (Choose all that apply.)
A. Link efficiency
B. Traffic shaping
C. Policing
D. Classification
E. Weighted Random Early Discard (WRED)

Correct Answer: CD Section: (none) Explanation
Explanation/Reference:
Explanation:

Committed Access Rate (CAR) provides the capability to allow the service provider to rate-limit traffic in and out of router interfaces, thereby enabling various forms of ingress and egress rate-limiting in a network. CAR is a policing mechanism, not a queuing mechanism. Therefore it does not buffer or delay packets, which do or do not conform to the policy, but simply rate-limits them according to a simple “forward or drop” policy, according to the configuration. CAR also uses a token-bucket metering mechanism, similar to GTS, but without a delay queue. The CAR rate-limiting feature manages a network’s access bandwidth policy by ensuring that traffic falling within specified rate parameters is sent, while dropping packets that exceed the acceptable amount of traffic or sending them with a different priority. CAR is often configured on interfaces at the edge of a network to limit traffic into or out of the network. CAR can also be used for packet marking. The operator can specify a policy that determines which packets should be assigned to which traffic class, and use CAR to implement the marking. The IP header already provides a mechanism to do this, namely the three precedence bits in the ‘type of service’ field in the IP header. CAR allows the setting of policies, based on information in the IP or TCP header such as IP address, application port, physical port or sub-interface, IP protocol, etc., to decide how the precedence bits should be marked or “colored.” Once marked, appropriate treatment can be given in the backbone to ensure that premium packets receive premium service in terms of bandwidth allocation, delay control, etc. Note CAR can also be used to police (or “recolor”) precedence bits set externally to the network either by the customer or by a downstream service provider. Thus the network can decide to either accept or override external decisions. CAR is implemented using the following abstract mechanisms: The classifier, which differentiates traffic into multiple classes, which may be treated in a discriminate manner The meter, which uses a token-bucket scheme to measure the rate of classified traffic The marker, which can be used to mark or re-mark classified traffic (for example, with precedence or DSCP values) The dropper, which may drop packets (in the rate-limiting scenario) according to the configured policy Source: Cisco IP QoS Traffic Shaping and Policing, Page 4-68
QUESTION 74
Which of the following are shaping characteristics, but not policing characteristics? (Choose all that apply.)
A. It forces TCP resends
B. It is rate limiting with no buffering mechanism
C. It can adapt to Frame Relay BECN and FECN
D. It is most typically performed on egress
E. None of the above.

Correct Answer: CD Section: (none) Explanation
Explanation/Reference:
QUESTION 75
Which of the following statements regarding the capabilities of CAR is valid? (Choose all that apply.)
A. It is capable of supporting both policing and shaping options.
B. It allows a conform, exceed and violate action.
C. It allows cascading rate policies, in order to allow for more granular rate limits.
D. It can be used as both input and output policer.
E. It can be applied to serial interfaces, as well as ATM and Frame Relay interfaces.

Correct Answer: CDE Section: (none) Explanation
Explanation/Reference:
QUESTION 76
Shaping is the process whereby traffic flow is examined and rates are measured. What is done to packets during the shaping process when it exceeds a threshold bit rate?
A. Packets are delayed (queued)
B. Packets are discarded
C. Packets that exceed a defined burst size as well, are delayed (queued)
D. Packets that exceed a defined burst size as well, are discarded

Correct Answer: C Section: (none) Explanation
Explanation/Reference:
Traffic that exceeds the BC value in time interval T will be queued. Ref http://www.cisco.com/en/US/tech/ CK5 43/ CK5 45/technologies_tech_note09186a00800a3a25.shtml
QUESTION 77
Per-Virtual Circuit (VC) congestion avoidance discard at Layer 2 has what consequence when the ingress ATM interface discards a fragment?
A. Incomplete data packets are sent and the entire data packet must be resent.
B. The entire data packet is discarded at the ingress interface and must be resent.
C. Incomplete data packets are sent and discarded packet fragments must be resent.
D. Data packets may be sent in cells that are out of order, causing the entire packet to be resent.

Correct Answer: BD Section: (none) Explanation Explanation/Reference:
QUESTION 78
What are three capabilities of the route map used in policy-based routing? (Choose three)
A. Rate limiting
B. Packet marking
C. Packet classification
D. Intelligent packet discard
E. Defining customized routing paths

Correct Answer: BCE Section: (none) Explanation
Explanation/Reference:
QUESTION 79
What are two services provided through Committed Access Rate (CAR)? (Choose two)
A. Policing
B. Classification
C. Link efficiency
D. Traffic shaping
E. Congestion avoidance

Correct Answer: AB Section: (none) Explanation
Explanation/Reference:
Explanation:
CAR provides policing functions and marking.
Policing, in its most basic form, discards traffic that exceeds a particular traffic contact. The contact has
two components: a rate, stated either in bits per second or bytes per second; and a butst size, statted in
either bits or bytes. The traffic conforms to the contract if it sends at the rate, or bellow, and it does not
send a burst of traffic greater than the burst size. If the traffic exceeds the traffic rate over time, or exceeds
the single burst size limit, the policing function drops the traffic in excess of the rate and the burst size.
Therefore, the simplest form of policing has two rigid actions: eigher to forward packets or to drop them.
Reference: DQOS Exam Certification Guide p.194.

QUESTION 80
Which of the following statements regarding class maps is valid? (Choose all that apply.)
A. It is possible to configure a class map within another class map.
B. Match commands are used to specify packet classification.
C. The default behavior is match-any regardless whether match-any or match-all is specified or not.
D. Traffic that does not have a match in the class map is placed in the default class.

Correct Answer: ABD Section: (none) Explanation
Explanation/Reference:
Incorrect:
C. The default mode is Match all.
Explanation: A class map is created using the class-map global configuration command. Class maps are identified by case-sensitive names. Each class map contains one or more conditions that determine if the packet belongs to the class. There are two ways of processing conditions when there is more than one condition in a class map: Match all-all conditions have to be met to bind a packet to the class Match any-at least one condition has to be met to bind the packet to the class The default match strategy of class maps is “Match all”. Source: Cisco IP QoS-Modular QoS CLI Classification, Page 8-6

QUESTION 81
Study the Exhibit below carefully: interface s0/0 custom-queue-list 5 ! queue-list 5 protocol ip 1 list 101 queue-list 5 queue 1 limit 40 queue-list 5 lowest-custom 2 queue-list 5 interface e0/0 2 queue-list 5 queue 2 byte-count 5000 queue-list 5 protocol ip 3 queue-list 5 queue 3 byte-count 5000 queue-list 5 queue 4 default ! access-list 101 permit ip any any precedence 5 According to the configuration in the exhibit, which queue is used for traffic from e0/0 with a precedence of five?
A. 1
B. 2
C. 3
D. 4
Correct Answer: A Section: (none) Explanation

Explanation/Reference:
Explanation:
Answer should be A because the queue-List is processed top to bottom, so the Precedence 5 is meet
before the interface ethernet 0/0.

QUESTION 82
Which of the following statements regarding the way in which Priority Queuing services its queues is valid?
A. The highest priority queue containing packets is serviced until it is empty.
B. The highest priority queue is always serviced first. The remaining queues are serviced in a TDM fashion.
C. A high priority queue is serviced until it is empty, only then will the service engine move to the next highest priority queue in a round-robin fashion.
D. The highest priority queue is allocated 50% of the available bandwidth. Each remaining queue is allocated half of the remaining bandwidth.

Correct Answer: C Section: (none) Explanation
Explanation/Reference:
Explanation:

Priority Queuing uses strict priority scheduling. As long as there are packets in the high queue no other queue will be served. If the high queue is empty the router starts serving the medium queue. Congestion in any of the queues, except the low queue, causes a different type of starvation. A congested higher-priority queue causes all lower-priority queues to starve (class starvation). Source: Cisco Queuing Mechanisms, Page 3-23
QUESTION 83
What is the default scheduling mechanism that Custom Queuing uses?
A. FIFO
B. top down
C. round robin
D. weighted
E. none of the above

Correct Answer: C Section: (none) Explanation
Explanation/Reference:
Explanation:

Custom Queuing (CQ) is similar to Priority Queuing in the way it is configured and in the supported classification options. The scheduling, however, is completely different. CQ uses up to 16 queues that can be used for user-defined classes. The classification options are identical to those of Priority Queuing. The scheduling mechanism uses the round-robin service where each queue is allowed to forward a certain number of bytes (not packets). Tail-drop is still used within each individual queue. Source: Cisco Queuing Mechanisms, Page 3-35
QUESTION 84
Exhibit: policy-map police 1 class bulk-ftp police cir percent 20 pir percent 40 conform-action set-dscp-transmit af11 exceed-action set-dscp-transmit 0 violate-action drop Based on the configuration, which two of the following statements are true? (choose two)
A. This configuration will use a single token buket
B. This configuration will drop all exceeding traffic
C. This is a dual-rate, class-based policing example
D. This is a percentage-based policing example
E. This is a multi-action, class-based policing example

Correct Answer: CD Section: (none) Explanation
Explanation/Reference:
Explanation:
The presence ofboth cir (Bc) and pir (Be)in the command make it a dual-rate policer. So C is a valid
answer.
The use of”percentage” makes D a valid answer.
Since all the “action” statements are on separate lines, it makes itmulti-action policing. However, there is
only one actual action being performed for each one. So E could be valid, and could not be valid.The
question states to choose two answers.

QUESTION 85
What are three key differences between Weighted Fair Queuing (WFQ) and distributed Weighted Fair Queuing (dWFQ)? (Choose three)
A. dWFQ distributes its queuing policy to its neighbor.
B. dWFQ requires a Versatile interface Processor (VIP) to operate.
C. dWFQ adds WFQ support on ATM, Fast EtherChannel, and tunnel interfaces.
D. dWFQ supports classed-based weighting based on TOS field and QoS Group settings.
E. In order to use dWFQ, distributed Cisco Express Forwarding (dCEF) must be enabled on the interface.

Correct Answer: BDE Section: (none) Explanation
Explanation/Reference:
Reference: Introduction to IP QoS p.4-18
QUESTION 86
When configuring Priority Queuing on Cisco IOS routers, which three steps are required? (Choose three)
A. Define the priority list.
B. Configure an ACL for traffic identification.
C. Assign packets to specific priority queues.
D. Specify the maximum size of the priority queues.
E. Assign the priority list to be a designated router interface.

Correct Answer: ACE Section: (none) Explanation
Explanation/Reference:
Explanation:
The configuration of Priority Queuing can be split into the following four steps:

1.
Classify data into four classes

2.
Assign a queue to each class

3.
Set the maximum queue size (if the default is not appropriate)

4.
Apply the priority queuing system to one or more interfaces Reference: Introduction to IP QoS p.3-25
QUESTION 87
What are two benefits of WFQ? (Choose two) A. WFQ is very easy to configure, and no manual traffic classification is necessary
B. WFQ can provide fixed-bandwidth and fixed-delay guarantees
C. WFQ can provide fixed-bandwidth guarantees
D. WFQ can provide fixed-delay guarantees
E. WFQ prevents the large-volume flows with large packet size from staring out the low-volums flows with small packet size.
F. Based on DSCP, WFQ allows weighted, random dropping of packets when the WFQ system is full

Correct Answer: AE Section: (none) Explanation
Explanation/Reference:
The Question is WFQ and not CBWFQ, so the Answer should be: A,E
QUESTION 88
Which two statements are true about the DSCP field in an IP header? (Choose two)
A. DSCP is the most significant six bits of the DS field
B. DSCP is the least significant six bits of the DS field
C. DSCP is used to select the type of service (ToS)
D. DSCP is used to select a per-hop behaviour (PHB)
E. DSCP is broken into four sub0fields
F. DSCP is broker into five sub-fields

Correct Answer: AD Section: (none) Explanation
Explanation/Reference:
Page 120-121, IP Telephony Self-Study Cisco DQOS Exam Certification Guide, http// www.ciscopress.com/title/1587200589
QUESTION 89
Study the Exhibit below carefully: interface s0/0 bandwidth 128 ip address 10.0.0.1 255.255.255.252 encapsulation ppp fair-queue ip rtp priority 16384 16383 50 According to the configuration in the exhibit, what is the amount of bandwidth available to the fair queues?
A. 46 Kbps
B. 50 Kbps
C. 65 Kbps
D. 78 Kbps
E. 128 Kbps

Correct Answer: A Section: (none) Explanation
Explanation/Reference:
Explanation: The sample configuration shows how 50 kbps of bandwidth is guaranteed for RTP traffic. The show queue command shows there is only 46 kbps of bandwidth (128 kbps * 75% -50 kbps = 46 kbps) remaining for WFQ. Source: Cisco Queuing Mechanisms, Page 3-140

QUESTION 90
Disregarding fragment size, which of the following LFI mechanism never fragments voice frames?
A. FRF .3
B. FRF.9
C. FRF.11 Annex C
D. FRF.6
E. FRF .12

Correct Answer: C Section: (none) Explanation
Explanation/Reference:
Explanation:
FRF.11 Annex C never fragment voice frames.
Only this LFI mechanism is used with voice traffic.
There are three LFI mechanisms implemented in Cisco IOS:
1) Multilink PPP with Interleaving is by far the most common and widely used form of LFI.
2) FRF.11 Annex C LFI is used with Voice over Frame Relay (VoFR).
3) FRF.12 Frame Relay LFI is used with Frame Relay data connections.
4) In an ATM network, using separate PVCs carrying voice and data can be used to interleave packets
when they are output on an interface.
Reference: Introduction to IP QoS p.6-47
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