Checkpoint Exam: Ethernet Concepts Exam
Which statement is true about the CSMA/CD access method that is used in Ethernet?
All network devices must listen before transmitting.
When the store-and-forward method of switching is in use, what part of the Ethernet frame is used to perform an error check?
CRC in the trailer
What are three ways that media access control is used in networking?
Data link layer protocols define the rules for access to different media. Media access control provides placement of data frames onto the media. Ethernet utilizes CSMA/CD (Carrier-Sense Multiple Access Collision Detection)
In addition to the cable length, what two factors could interfere with the communication carried over UTP cables?
Electromagnetic interference Crosstalk
Which statement describes an extended star topology?
End devices connect to a central intermediate device, which in turn connects to other central intermediate devices.
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?
Frame Check Sequence minimum frame size
What is the auto-MDIX feature?
It enables a device to automatically configure an interface to use a straight-through or a crossover cable.
What are two characteristics of fiber-optic cable?
It is not affected by EMI or RFI It is more expensive than UTP cabling is.
What is a characteristic of the LLC (Logical Link Control) sublayer?
It places information in the frame allowing multiple Layer 3 protocols to use the same network interface and media.
What functions are performed at the MAC sublayer of the OSI data link layer?
Provides synchronization between source and target nodes. Integrates various physical technologies. Implements a trailer to detect transmission errors. Controls the NIC responsible for sending and receiving data on the physical medium. Provides a mechanism to allow multiple devices to communicate over a shared medium.
A network administrator is connecting two modern switches using a straight-through cable. The switches are new and have never been configured. Which three statements are correct about the final result of the connection?
The auto-MDIX feature will configure the interfaces eliminating the need for a crossover cable. The link between switches will work as full-duplex. The link between the switches will work at the fastest speed that is supported by both switches.
What action will occur if a host receives a frame with a destination MAC address of FF:FF:FF:FF:FF:FF?
The host will process the frame.
With the use of unshielded twisted-pair copper wire in a network, what causes crosstalk within the cable pairs?
The magnetic field around the adjacent pairs of wire
Which statement describes a characteristic of the frame header fields of the data link layer?
They vary depending on protocols.
What OSI physical layer term describes the physical medium which uses electrical pulses?
copper cable
What is a primary role of the Physical layer in transmitting data on the network?
create the signals that represent the bits in each frame on to the media
What cable is used to connect two routers together without auto-MDIX?
crossover
What three items are contained in an Ethernet header and trailer?
destination MAC address source MAC address error-checking information
Which media communication type does not require media arbitration in the data link layer?
full-duplex
What makes fiber preferable to copper cabling for interconnecting buildings?
greater distances per cable run greater bandwidth potential limited susceptibility to EMI/RFI
What is one advantage of using the cut-through switching method instead of the store-and-forward switching method?
has a lower latency appropriate for high-performance computing applications
Which three basic parts are common to all frame types supported by the data link layer?
header trailer data
What does the term "attenuation" mean in data communication?
loss of signal strength as distance increases
What cable is needed to connect a PC to the console port on a switch?
rollover
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?
shared memory buffering
Which switching method uses the CRC (Cyclic Redundancy Check) value in a frame?
store-and-forward
Which frame forwarding method receives the entire frame and performs a CRC check to detect errors before forwarding the frame?
store-and-forward switching
What cable is need to connect a switch and a router together?
straight-through
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?
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 is the purpose of the FCS (Field Check Sequence) field in a frame?
to determine if errors occurred in the transmission and reception
What are two actions performed by a Cisco switch?
using the source MAC addresses of frames to build and maintain a MAC address table utilizing the MAC address table to forward frames via the destination MAC address
