CCNA1-Module 6

1 Refer to the exhibit. Host A is communicating with host F. What happens to a frame sent from host A to host F as it travels over the Ethernet segments?

  • The frame format is modified as it passes through each switch.
  • The frame format remains the same across each Ethernet segment.*
  • The frame format is modified as the media speed changed at switch B and switch E.
  • The frame format is modified as the media material changes between copper and fiber at switch C and switch D.

2 Which of the following are specified by IEEE standards as sublayers of the OSI data link layer? (Choose two.)

  • Logical Link Control*
  • Logical Layer Control
  • Media Access Control*
  • Logical Link Communication
  • Media Access Communication
  • Physical Access Communication

3 In which two layers of the OSI model does Ethernet function? (Choose two.)

  • Application
  • session
  • Transport
  • network
  • data link*
  • Physical*

4 Which statement describes how CSMA/CD on an Ethernet segment manages the retransmission of frames after a collision occurs?

  • The first device to detect the collision has the priority for retransmission.
  • The device with the lowest MAC address determines the retransmission priority.
  • The devices on the network segment hold an election for priority to retransmit data
  • The devices transmitting when the collision occurs DO NOT have priority for retransmission.*

5 Which two devices can provide full-duplex Ethernet connections? (Choose two.)

  • Hub
  • Modem
  • repeater
  • NIC*
  • Layer 2 switch*

6 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.*
  • Only one of the devices can transmit at a time.
  • The switch will have priority for transmitting data.
  • The devices will default back to half duplex if excessive collisions occur.

7 Refer to the exhibit. All hosts are in listen mode. Host 1 and Host 4 both transmit data at the same time. How do the hosts respond on the network? (Choose two.)

  • Hosts 1 and 4 may be operating full duplex so no collision will exist.
  • The hub will block the port connected to Host 4 to prevent a collision.
  • After the end of the jam signal, a backoff algorithm is invoked.*
  • Hosts 1 and 4 are assigned shorter backoff values to provide them priority to access the media.
  • If a host has data to transmit after the backoff period of that host, the host checks to determine if the line is idle, before transmitting.*

8 A router has an Ethernet, Token Ring, serial, and ISDN interface. Which interfaces will have a MAC address?

  • serial and ISDN interfaces
  • Ethernet and Token Ring interfaces*
  • Ethernet and ISDN interfaces
  • Token Ring and serial interfaces

9 What are three functions of a NIC in a PC? (Choose three.)

  • A NIC connects the PC to the network media.*
  • A NIC detects collisions on the Ethernet segment.*
  • A NIC checks the formatting of data before it is transmitted.
  • A NIC passes the contents of selected frames to the upper OSI layers.*
  • A NIC acknowledges and retransmits data that was not received properly.
  • A NIC discards frames when the destination IP address does not match the local host.

10 On a local area network, one workstation can send data on the line while it is receiving data. What type of data transfer does this describe?

  • hybrid
  • half duplex
  • full duplex*
  • Multilink

11 In an Ethernet LAN, how does the NIC know when it can transmit data?

  • An Ethernet NIC transmits data as soon as the frame is received.
  • An Ethernet NIC transmits data as soon as the NIC receives a token.
  • An Ethernet NIC transmits data when it senses a collision.
  • An Ethernet NIC transmits data after listening for the absence of a signal on the media.*

12 Which characteristics describe carrier sense multiple access collision detect (CSMA/CD)? (Choose three.)

  • reliable
  • point-to-point
  • Nondeterministic*
  • connection-oriented
  • collision environment*
  • first-come, first-served approach*

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

  • A random delay is used to ensure a collision-free link.
  • A random delay value for each device is assigned by the manufacturer.
  • A standard delay value could not be agreed upon among networking device vendors.
  • +A random delay helps prevent the stations from experiencing another collision during the transmission.*

14 At what layer of the OSI model does a MAC address reside?

  • 1
  • 2*
  • 3
  • 4
  • 7

15 Where does the MAC address originate?

  • DHCP server database
  • configured by the administrator
  • burned into ROM on the NIC card*
  • network configuration on the computer
  • included in the creation of the processor chip

16 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.*
  • The hosts creating the collision have priority to send data.
  • The hosts creating the collision retransmit the last 16 frames.
  • The hosts extend their delay period to allow for rapid transmission.

17 Refer to the exhibit. The small office network shown in the exhibit consists of four computers connected through a hub. Which configuration would cause collisions and errors on the network?

  • autonegotiation
  • FastEthernet
  • peer-to-peer shared resources
  • administratively configured full duplex*

18 How many hexadecimal digits are in a MAC address?

  • 2
  • 8
  • 12*
  • 16
  • 32

19 Refer to the exhibit. A technician wants to increase the available bandwidth for the workstation by allowing the switch and the NIC on the workstation to transmit and receive simultaneously. What will permit this?

  • full-duplex*
  • FastEthernet
  • crossover cable

Di Posting pada 11:30:50 31-09-2009
Label CCNA
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