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?

• CSMA/CD
• full-duplex*
• FastEthernet
• crossover cable