CCNA Exploration - Chapter 9

chapter 9 - correct answers

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1 In the graphic, Host A has reached 50% completion in sending a 1 KB Ethernet frame to Host D when Host B wishes to transmit its own frame to Host C. What must Host B do?

--> Host B must wait until it is certain that Host A has completed sending its frame.


2 Ethernet operates at which layers of the OSI model? (Choose two.)

--> Physical layer

-->Data-link layer


3 Which of the following describe interframe spacing? (Choose two.)

--> the minimum interval, measured in bit-times, that any station must wait before sending another frame

--> the time allowed for slow stations to process a frame and prepare for the next frame


4 What three primary functions does data link layer encapsulation provide? (Choose three.)

--> addressing

--> error detection

--> frame delimiting


5 When a collision occurs in a network using CSMA/CD, how do hosts with data to transmit respond after the backoff period has expired?

--> The hosts return to a listen-before-transmit mode.


6 What are three functions of the upper data link sublayer in the OSI model? (Choose three.)

--> identifies the network layer protocol

--> makes the connection with the upper layers

--> insulates network layer protocols from changes in physical equipment determines the source of a transmission when multiple devices are transmitting


7 What does the IEEE 802.2 standard represent in Ethernet technologies?

--> Logical Link Control sublayer


8 Why do hosts on an Ethernet segment that experience a collision use a random delay before attempting to transmit a frame?

--> A random delay helps prevent the stations from experiencing another collision during the transmission.


9 Refer to the exhibit. Which option correctly matches the frame field type with the contents that frame field includes?

--> data field - network layer packet


10 Host A has an IP address of 172.16.225.93 and a mask of 255.255.248.0. Host A needs to communicate with a new host whose IP is 172.16.231.78. Host A performs the ANDing operation on the destination address. What two things will occur? (Choose two.)

--> Host A will broadcast an ARP request for the MAC of the destination host.

--> A result of 172.16.224.0 will be obtained.


11 Which of the following is a drawback of the CSMA/CD access method?

--> Collisions can decrease network performance.


12 Ethernet operates at which layer of the TCP/IP network model?

--> network access


13 What is the primary purpose of ARP?

--> resolve IPv4 addresses to MAC addresses


14 Refer to the exhibit. The switch and workstation are administratively configured for full-duplex operation. Which statement accurately reflects the operation of this link?

--> No collisions will occur on this link.


15 Refer to the exhibit. Host_A is attempting to contact Server_B. Which statements correctly describe the addressing Host_A will generate in the process? (Choose two.)

--> A frame with the destination MAC address of Router_A.

--> A packet with the destination IP of Server_B.


16 Which statements correctly describe MAC addresses? (Choose three.)

--> copied into RAM during system startup

--> contains a 3 byte OUI

--> 6 bytes long


17 Which two features make switches preferable to hubs in Ethernet-based networks? (Choose two.)

--> minimizing of collisions

--> increase in the throughput of communications


18 What are the two most commonly used media types in Ethernet networks today? (Choose two.)

--> copper UTP

--> optical fiber


19 Convert the binary number 10111010 into its hexadecimal equivalent. Select the correct answer from the list below.

--> BA


20 After an Ethernet collision, when the backoff algorithm is invoked, which device has priority to transmit data?

--> any device in the collision domain whose backoff timer expires