Ccna

Question 1

What is the purpose of the OSI physical layer?

Answer 1

transmitting bits across the local media

Question 2

Why are two strands of fiber used for a single fiber optic connection?

Answer 2

They allow for full-duplex connectivity.

Question 3

Which procedure is used to reduce the effect of crosstalk in copper cables?

Answer 3

twisting opposing circuit wire pairs together

Question 4

Which characteristic describes crosstalk?

Answer 4

the distortion of the transmitted messages from signals carried in adjacent wires

Question 5

A network administrator is measuring the transfer of bits across the company backbone for a mission critical financial application. The administrator notices that the network throughput appears lower than the bandwidth expected. Which three factors could influence the differences in throughput? (Choose three.)

Answer 5

“the amount of traffic that is currently crossing the network
“the type of traffic that is crossing the network
“the latency that is created by the number of network devices that the data is crossing

Question 6

What are two characteristics of fiber-optic cable? (Choose two.)

Answer 6

It is not affected by EMI or RFI.
It is more expensive than UTP cabling is.

Question 7

What is a primary role of the Physical layer in transmitting data on the network?

Answer 7

create the signals that represent the bits in each frame on to the media

Question 8

With the use of unshielded twisted-pair copper wire in a network, what causes crosstalk within the cable pairs?

Answer 8

the magnetic field around the adjacent pairs of wire

Question 9

Refer to the graphic. What type of cabling is shown?

Answer 9

Fiber

Question 10

In addition to the cable length, what two factors could interfere with the communication carried over UTP cables? (Choose two.)

Answer 10

crosstalk
electromagnetic interference

Question 11

Refer to the graphic. What type of cabling is shown?

Answer 11

UTP

Question 12

Which two devices commonly affect wireless networks? (Choose two.)

Answer 12

cordless phones
microwaves

Question 13

Which two statements describe the services provided by the data link layer? (Choose two.)

Answer 13

It manages the access of frames to the network media.
It packages various Layer 3 PDUs into a frame format that is compatible with the network interface.

Question 14

What is the function of the CRC value that is found in the FCS field of a frame?

Answer 14

to verify the integrity of the received frame

Question 15

What is contained in the trailer of a data-link frame?

Answer 15

error detection

Question 16

Which statement describes a characteristic of the frame header fields of the data link layer?

Answer 16

They vary depending on protocols.

Question 17

A network team is comparing physical WAN topologies for connecting remote sites to a headquarters building. Which topology provides high availability and connects some, but not all, remote sites?

Answer 17

partial mesh

Question 18

Which two fields or features does Ethernet examine to determine if a received frame is passed to the data link layer or discarded by the NIC? (Choose two.)

Answer 18

Frame Check Sequence
minimum frame size

Question 19

Which media communication type does not require media arbitration in the data link layer?

Answer 19

full-duplex

Question 20

Which statement describes an extended star topology?

Answer 20

End devices connect to a central intermediate device, which in turn connects to other central intermediate devices.

Question 21

What is a characteristic of the LLC sublayer?

Answer 21

It places information in the frame allowing multiple Layer 3 protocols to use the same network interface and media.

Question 22

What are three ways that media access control is used in networking? (Choose three.)

Answer 22

Ethernet utilizes CSMA/CD.
Media access control provides placement of data frames onto the media.
Data link layer protocols define the rules for access to different media.

Question 23

During the encapsulation process, what occurs at the data link layer for a PC connected to an Ethernet network?

Answer 23

The physical address is added.

Question 24

What three items are contained in an Ethernet header and trailer? (Choose three.)

Answer 24

source MAC address
destination MAC address
error-checking information

Question 25

What type of communication rule would best describe CSMA/CD?

Answer 25

access method

Question 26

Which three basic parts are common to all frame types supported by the data link layer? (Choose three.)

Answer 26

header
Data
Trailer

Question 27

Which statement is true about the CSMA/CD access method that is used in Ethernet?

Answer 27

All network devices must listen before transmitting.

Question 28

What is the auto-MDIX feature on a switch?

Answer 28

the automatic configuration of an interface for a straight-through or a crossover Ethernet cable connection

Question 29

Refer to the exhibit. What is the destination MAC address of the Ethernet frame as it leaves the web server if the final destination is PC1?

Answer 29

00-60-2F-3A-07-CC

Question 30

A Layer 2 switch is used to switch incoming frames from a 1000BASE-T port to a port connected to a 100Base-T network. Which method of memory buffering would work best for this task?

Answer 30

shared memory buffering

Question 31

What are two examples of the cut-through switching method? (Choose two.)

Answer 31

fast-forward switching
fragment-free switching

Question 32

Which frame forwarding method receives the entire frame and performs a CRC check to detect errors before forwarding the frame?

Answer 32

store-and-forward switching