H12-224 : HCNP-R&S Fast Track (Huawei Certified Network Professional – Routing & Switching Fast Track) : Part 12

H12-224 : HCNP-R&S Fast Track (Huawei Certified Network Professional – Routing & Switching Fast Track) : Part 12

1. Which of the following PHB types are defined in IETF DiffServ? (Choose three.)

   • Default PH 
   • Class-Selector PHB 
   • Fast Forwarding PHB
   • Assured Forwarding PHB 

2. Which of the following statements are correct regarding the function of VRRP?

   • VRRP can improve the reliability of default gateway. 
   • VRRP increase the convergence speed of routing protocol.
   • VRRP is mainly used for traffic balance.
   • VRRP can provide one default gateway for different network segments, it simplifies the gateway configuration for PC.

3. Which of the following statements are correct regarding priority in VRRP?

   • The IP address owner always uses 255 as its priority regardless its config priority. 
   • The IP address owner always uses 0 as its priority regardless its config priority.
   • We can configure the priority as 0 to make the router never attend the Master election.
   • If a VRRP router changes from Master to Slave, it will send out a VRRP message with priority 0 in the network.

4. Which of the following statements about a backup router in a VRRP backup group are true? (Choose three.)

   • It receives VRRP packets from the master router and determines whether the master router is functioning properly.
   • It does not respond to the ARP requests sent from a virtual IP address.
   • It forwards an IP packet whose destination MAC address is a virtual MAC address.
   • It discards an IP packet whose destination IP address is a virtual IP address.

5. Most fields in IP headers of packets in the same data flow are identical. You can compress these fields to improve the link transmission efficiency.

   • True 
   • False

6. When a local BFD session in the Init state receives packets with the Stat field being Down, the local BFD session changes its status to Down.

   • True 
   • False

7. In traffic shaping, the packet whose transmission rate exceeds the rate limit will be discarded or re-marked.

   • True
   • False 

8. BFD packets are classified into control packets and echo packets.

   • True 
   • False

9. Assume that the following WRED policies are used in QoS:

   The length of the queue for saving DSCP packets with the priority being AF21 ranges from 35 to 40.
   The length of the queue for saving DSCP packets with the priority being AF22 ranges from 30 to 40.
   The length of the queue for saving DSCP packets with the priority being AF23 ranges from 25 to 40.
   In the case of congestion, DSCP packets with which of the following priority value will be discarded first?

   • AF21
   • AF22
   • AF23 
   • All the same

10. Availability identifies the utility of a system. The availability of the system increases if the MTBF decreases or the MTTR increases.

    • True
    • False 

11. Traffic policing usually uses which of the following QoS technologies?

    • GTS
    • LR
    • CAR 
    • WRED

12. Assume that there are four flows a, b, c, and d, the transmission rate of each flow is 50 Mbit/s, and the total bandwidth of the interface for flow transmission is 100 Mbit/s. In the case of congestion, PQ is available for flow a. WFQ is available for flows b, c, and d, with the weight proportion being 1:2:3:4. Which of the following statement about the interface bandwidth allocated to each flow is true? (Choose two.)

    • The interface bandwidth allocated to flow a is 100 Mbit/s.
    • The interface bandwidth allocated to flow a is 50 Mbit/s. 
    • The interface bandwidth allocated to flows b is 10 Mbit/s and interface bandwidths allocated to flows c and d are 20 Mbit/s each. 
    • The interface bandwidth allocated to flows b is 25 Mbit/s and interface bandwidths allocated to flows c and d are 12.5 Mbit/s each.

13. Which of the following statements about the VRRP working process is false?

    • The router with the highest priority is elected as the master router.
    • The master router sends gratuitous ARP packets to inform connected devices or hosts of its virtual MAC address.
    • If the master router fails, the backup router with the highest priority is elected as the new master router.
    • To ensure fast convergence, a backup router immediately becomes the master router if the priority of the backup router is higher than the priority of the master router. 

14. Based on fields IP precedence, MPLS EXP, or 802.1p, packets can be classified into how many service types?

    • 4
    • 6
    • 7
    • 8

15. IP network can provide various packet forwarding service, the service demands that users care during packet forwarding include. (Choose three.)

    • Throughput 
    • Delay 
    • Cost
    • Loss of packet 

16. QoS includes which of the following aspects? (Choose three.)

    • Transmission bandwidth 
    • Transmission delay and jitter 
    • Packet loss ratio 
    • Network security

17. Which of the following link efficiency mechanism can be used to compress RTP and TCP packet headers?

    • IPHC 
    • LFI
    • PPP
    • All of the above

18. The Committed Access Rate (CAR) technology uses the token bucket (TB) to control traffic.

    • True 
    • False

19. Which of the following statements about the jitter and delay are true? (Choose three.)

    • The end-to-end delay is the sum of transmission delays, processing delays, and queuing delays along the packet forwarding path. 
    • The variation in packet delay is called jitter. 
    • The jitter depends on the delay. The lower the delay, the less the jitter. 
    • The jitter is independent of the delay.

20. Assume that congestion occurs on the outbound interface, packet A is cached in the PQ, and packet B is cached in the WFQ, which of the following statement about packet scheduling is true?

    • Packet A is scheduled first. 
    • Packet B is scheduled first.
    • Packets A and B are scheduled at the same time.
    • Packets A and B are discarded.