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Ngo Thanh Hien - Take Exam Exam questions Time remaining: 00: 49: 56 1 . Which of the following choices represent the fundamental intelligent network services in Cisco’s AVVID? (Select four) Quality of Service (QoS) Reduces cost Mobility and scalability Security High availability 2 . What security policies should be implemented at the core? Access-lists Port security Quality of Service commands for congestion management and avoidance Traffic Filters 3 . Which QoS mechanisms can you use on a converged network to improve VoIP quality? (Select three) The use of a queuing method that will give VoIP traffic strict priority over other traffic. The use of RTP header compression for the VoIP traffic. The proper classification and marking of the traffic as close to the source as possible. The use of 802.1QinQ trunking for VoIP traffic. The use of WRED. 4 . Switch SW1 is an IOS-based switch. Which command could an administrator use to establish a traffic policy on this IOS based switch? traffic-list route-map policy-map policy-list None of the above 5 . WRED is being configured on different network devices throughout the Cisco network. What is true about WRED? Cisco Express Forwarding cannot be enabled with WRED. WRED is useful when the bulk of traffic is not TCP/IP. The rate of packet-drop decreases as the average queue size increases, until the average queue size reaches the maximum threshold. Packets not flagged by IP precedence are randomly dropped when the average queue depth is above the minimum threshold. WRED defines packet-drop probability using an access list. All of the above. 6 . By default, which IP Precedence value is a DSCP value of 42 mapped? 0 1 2 3 4 5 7 . When a PC is connected to the PC switch port on an IP Phone, how is QoS trust handled? The IP Phone always trusts the class of service (CoS) information coming from the PC. The IP Phone never trusts the PC and always overwrites the CoS bits. QoS trust for the PC data is handled at the Catalyst switch port, not the IP Phone. The Catalyst switch instructs the IP Phone how to trust the PC QoS information. 8 . Which of the following QoS technologies classifies traffic entering a queue and services traffic based on dynamically observed traffic flows? FIFO WFQ Custom Queuing Priority Queuing 9 . FIFO (First-In-First-Out) queue is associated with which QoS model? Less than Best Effort Model Best Effort Model Differentiated Services Model (DiffServ) Integrated Services Model (IntServ) None of the above 10 . In the three-layer hierarchical network design model; what’s associated with the access layer? (Select two) optimized transport structure high port density boundary definition data encryption local VLANs route summaries 11 . You are a system administrator and you’ve recently implemented ‘tail drops’ on your network as a congestion avoidance mechanism. Which QoS technique can you use to avoid the potential problems caused by tail drops? CAR WRED CBWFQ RSVP 12 . What kinds of losses are observed on healthy networks during brief periods of congestion? Loss due to jitter. Loss due to delay. Loss due to noise. Loss due to deliberately dropped packets. 13 . Which of the following network problems would indicate a need to implement QoS features? (Select three) mis-routed packets excess jitter delay of critical traffic packet loss due to congestion data link layer broadcast storms ftp connections unsuccessful 14 . Someone asks you a question, “If I wanted to configure congestion avoidance, what mechanism randomly drops packets with a certain IP precedence value when the buffers fill to a predefined threshold?” Which mechanism is she asking about? WFQ CQ LLQ WRED tail drop 15 . What command is used to create a traffic policy on a Cisco IOS-based switch? route-map traffic-list policy-map policy-list 16 . Which command would you enter if you had a Cisco 3550 switch, and you wanted to configure priority queuing on your gig0/1 interface? Under the global configuration, configure "priority-queue out" Under the global configuration, configure "interface priority-queue gig0/1" Under the interface gig0/1, configure "priority-queue out" Priority queuing is on by default 17 . Which QoS technique avoids the problems that occur when tail drops are used as the congestion avoidance mechanism on the router? RSVP WRED CAR CBWFQ 18 . The Cisco network is using WRED for some QoS functions. Which characteris-tic best describes weighted random early detection (WRED)? It is well suited for UDP packets because of their connectionless state. It takes advantage of the TCP congestion control mechanism and drops packets selectively based on IP precedence. It should be used in multi-protocol environments where IPX/SPX packet can be dropped instead of UDP packets. It ensures that flows that use the least bandwidth are more likely to have pack-ets dropped. None of the above. 19 . The TestKing network is utilizing QoS techniques to prioritize their mission critical data. What’s true about implementing QoS at the access, distribution, and core layers? (Select two) QoS implementation is the same for the access, distribution, and core layers. Classification and Marking should be done at the access layer. No QoS mechanisms are configured at the access layer since access layer switches like the atalyst 2950 are not QoS capable. The high speed core layer only requires proper queuing (like LLQ) and dropping (like WRED) configurations. 20 . Which of the characteristics below is associated with the (QoS) Integrated Ser- Ngo Thanh Hien - Take Exam Exam questions Time remaining: 00: 49: 56 1 . Which of the following choices represent the fundamental intelligent network services in Cisco’s AVVID? (Select four) Quality of Service (QoS) Reduces cost Mobility and scalability Security High availability 2 . What security policies should be implemented at the core? Access-lists Port security Quality of Service commands for congestion management and avoidance Traffic Filters 3 . Which QoS mechanisms can you use on a converged network to improve VoIP quality? (Select three) The use of a queuing method that will give VoIP traffic strict priority over other traffic. The use of RTP header compression for the VoIP traffic. The proper classification and marking of the traffic as close to the source as possible. The use of 802.1QinQ trunking for VoIP traffic. The use of WRED. 4 . Switch SW1 is an IOS-based switch. Which command could an administrator use to establish a traffic policy on this IOS based switch? . bits. QoS trust for the PC data is handled at the Catalyst switch port, not the IP Phone. The Catalyst switch instructs the IP Phone how to trust the PC QoS. The TestKing network is utilizing QoS techniques to prioritize their mission critical data. What’s true about implementing QoS at the access, distribution,