CCNA 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 How many hexadecimal digits are in a MAC address?

2
8
*12
16
32


3 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.


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

1
*2
3
4
7


5 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




6 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.


7 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




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

hub
modem
repeater
*NIC
* Layer 2 switch


9 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


10 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



11 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.


12 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, Hosts 1, 2, 3, and 4 invoke a backoff algorithm.
When the four hosts detect the collision, Hosts 1, 2, 3, and 4 generate a jam signal.
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.



13 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.



14 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.

15 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




16 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.



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

application
session
transport
network
*data link
* physical



18 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


19 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