Netcomms M4-M7 Flashcards
What is the purpose of the OSI physical layer?
Choices:
controlling access to media
transmitting bits across the local media
performing error detection on received frames
exchanging frames between nodes over physical network media
transmitting bits across the local media
Why are two strands of fiber used for a single fiber optic connection?
Choices:
The two strands allow the data to travel for longer distances without degrading.
They prevent crosstalk from causing interference on the connection.
They increase the speed at which the data can travel.
They allow for full-duplex connectivity.
They allow for full-duplex connectivity.
Which characteristic describes crosstalk?
Choices:
the distortion of the network signal from fluorescent lighting
the distortion of the transmitted messages from signals carried in adjacent wires
the weakening of the network signal over long cable lengths
the loss of wireless signal over excessive distance from the access point
the distortion of the transmitted messages from signals carried in adjacent wires
Which procedure is used to reduce the effect of crosstalk in copper cables?
Choices:
requiring proper grounding connections
twisting opposing circuit wire pairs together
wrapping the bundle of wires with metallic shielding
designing a cable infrastructure to avoid crosstalk interference
avoiding sharp bends during installation
twisting opposing circuit wire pairs together
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.)
Choices:
the amount of traffic that is currently crossing the network
the sophistication of the encapsulation method applied to the data
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
the bandwidth of the WAN connection to the Internet
the reliability of the gigabit Ethernet infrastructure of the backbone
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
What are two characteristics of fiber-optic cable? (Choose two.)
Choices:
It is not affected by EMI or RFI.
Each pair of cables is wrapped in metallic foil.
It combines the technique of cancellation, shielding, and twisting to protect data.
It typically contains 4 pairs of fiber-optic wires.
It is more expensive than UTP cabling is.
It is not affected by EMI or RFI.
It is more expensive than UTP cabling is.
What is a primary role of the Physical layer in transmitting data on the network?
Choices:
create the signals that represent the bits in each frame on to the media
provide physical addressing to the devices
determine the path packets take through the network
control data access to the media
create the signals that represent the bits in each frame on to the media
With the use of unshielded twisted-pair copper wire in a network, what causes crosstalk within the cable pairs?
Choices:
the magnetic field around the adjacent pairs of wire
the use of braided wire to shield the adjacent wire pairs
the reflection of the electrical wave back from the far end of the cable
the collision caused by two nodes trying to use the media simultaneously
the magnetic field around the adjacent pairs of wire
Refer to the graphic. What type of cabling is shown?
Choices:
STP
UTP
coax
fiber
fiber
In addition to the cable length, what two factors could interfere with the communication carried over
UTP cables? (Choose two.)
Choices:
crosstalk
bandwidth
size of the network
signal modulation technique
electromagnetic interference
crosstalk
electromagnetic interference
Refer to the graphic. What type of cabling is shown?
Choices:
STP
UTP
coax
fiber
UTP
Which two devices commonly affect wireless networks? (Choose two.)
Choices:
Blu-ray players
home theaters
cordless phones
microwaves
incandescent light bulbs
external hard drives
cordless phones
microwaves
Which two statements describe the services provided by the data link layer? (Choose two.)
Choices:
It defines the end-to-end delivery addressing scheme.
It maintains the path between the source and destination devices during the data transmission.
It manages the access of frames to the network media.
It provides reliable delivery through link establishment and flow control.
It ensures that application data will be transmitted according to the prioritization.
It packages various Layer 3 PDUs into a frame format that is compatible with the network interface.
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.
What is the function of the CRC value that is found in the FCS field of a frame?
Choices:
to verify the integrity of the received frame
to verify the physical address in the frame
to verify the logical address in the frame
to compute the checksum header for the data field in the frame
to verify the integrity of the received frame
What is contained in the trailer of a data-link frame?
Choices:
logical address
physical address
data
error detection
error detection
Which statement describes a characteristic of the frame header fields of the data link layer?
Choices:
They all include the flow control and logical connection fields.
Ethernet frame header fields contain Layer 3 source and destination addresses.
They vary depending on protocols.
They include information on user applications.
They vary depending on protocols.
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?
Choices:
mesh
partial mesh
hub and spoke
point-to-point
partial mesh
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.)
Choices:
auto-MDIX
CEF
Frame Check Sequence
minimum frame size
source MAC address
Frame Check Sequence
minimum frame size
Which media communication type does not require media arbitration in the data link layer?
Choices:
deterministic
half-duplex
full-duplex
controlled access
full-duplex
Which statement describes an extended star topology?
Choices:
End devices connect to a central intermediate device, which in turn connects to other central intermediate devices.
End devices are connected together by a bus and each bus connects to a central intermediate device.
Each end system is connected to its respective neighbor via an intermediate device.
All end and intermediate devices are connected in a chain to each other.
End devices connect to a central intermediate device, which in turn connects to other central intermediate devices.
What is a characteristic of the LLC sublayer?
Choices:
It provides the logical addressing required that identifies the device.
It provides delimitation of data according to the physical signaling requirements of the medium.
It places information in the frame allowing multiple Layer 3 protocols to use the same network interface and media.
It defines software processes that provide services to the physical layer.
It places information in the frame allowing multiple Layer 3 protocols to use the same network interface and media.
What are three ways that media access control is used in networking? (Choose three.)
Choices:
Ethernet utilizes CSMA/CD.
Media access control provides placement of data frames onto the media.
Contention-based access is also known as deterministic.
802.11 utilizes CSMA/CD.
Data link layer protocols define the rules for access to different media.
Networks with controlled access have reduced performance due to data collisions.
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.
During the encapsulation process, what occurs at the data link layer for a PC connected to an Ethernet network?
Choices:
An IP address is added.
The logical address is added.
The physical address is added.
The process port number is added.
The physical address is added.
What three items are contained in an Ethernet header and trailer? (Choose three.)
Choices:
source IP address
source MAC address
destination IP address
destination MAC address
error-checking information
source MAC address
destination MAC address
error-checking information
What type of communication rule would best describe CSMA/CD?
Choices:
access method
flow control
message encapsulation
message encoding
access method
Which three basic parts are common to all frame types supported by the data link layer? (Choose three.)
Choices:
header
type field
MTU size
data
trailer
CRC value
header
data
trailer
Which statement is true about the CSMA/CD access method that is used in Ethernet?
Choices:
When a device hears a carrier signal and transmits, a collision cannot occur.
A jamming signal causes only devices that caused the collision to execute a backoff algorithm.
All network devices must listen before transmitting.
Devices involved in a collision get priority to transmit after the backoff period.
All network devices must listen before transmitting.
What is the auto-MDIX feature on a switch?
Choices:
the automatic configuration of an interface for 10/100/1000 Mb/s operation
the automatic configuration of an interface for a straight-through or a crossover Ethernet cable connection
the automatic configuration of full-duplex operation over a single Ethernet copper or optical cable
the ability to turn a switch interface on or off accordingly if an active connection is detected
the automatic configuration of an interface for a straight-through or a crossover Ethernet cable connection
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?
Choices:
00-60-2F-3A-07-AA
00-60-2F-3A-07-BB
00-60-2F-3A-07-CC
00-60-2F-3A-07-DD
00-60-2F-3A-07-CC
