Ethernet Concepts Flashcards
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.)
A. the amount of traffic that is currently crossing the network
B. the sophistication of the encapsulation method applied to the data
C. the type of traffic that is crossing the network
D. the latency that is created by the number of network devices that the data is crossing
E. the bandwidth of the WAN connection to the Internet
F. the reliability of the gigabit Ethernet infrastructure of the backbone
Answer: ACD
What are two characteristics of fiber-optic cable? (Choose two.)
A. It is not affected by EMI or RFI.
B. Each pair of cables is wrapped in metallic foil.
C. It combines the technique of cancellation, shielding, and twisting to protect data.
D. It typically contains 4 pairs of fiber-optic wires.
E. It is more expensive than UTP cabling is.
Answer: AE
What is a primary role of the Physical layer in transmitting data on the network?
A. create the signals that represent the bits in each frame on to the media
B. provide physical addressing to the devices
C. determine the path packets take through the network
D. control data access to the media
Answer: A
With the use of unshielded twisted-pair copper wire in a network, what causes crosstalk within the cable pairs?
A. the magnetic field around the adjacent pairs of wire
B. the use of braided wire to shield the adjacent wire pairs
C. the reflection of the electrical wave back from the far end of the cable
D. the collision caused by two nodes trying to use the media simultaneously
Answer: A
In addition to the cable length, what two factors could interfere with the communication carried over UTP cables? (Choose two.)
A. crosstalk B. bandwidth C. size of the network D. signal modulation technique E. electromagnetic interference
Answer: AE
Which two devices commonly affect wireless networks? (Choose two.)
A. Blu-ray players B. home theaters C. cordless phones D. microwaves E. incandescent light bulbs F. external hard drives
Answer: CD
Which two statements describe the services provided by the data link layer? (Choose two.)
A. It defines the end-to-end delivery addressing scheme.
B. It maintains the path between the source and destination devices during the data transmission.
C. It manages the access of frames to the network media.
D. It provides reliable delivery through link establishment and flow control.
E. It ensures that application data will be transmitted according to the prioritization.
F. It packages various Layer 3 PDUs into a frame format that is compatible with the network interface.
Answer: CF
What is the function of the CRC value that is found in the FCS field of a frame?
A. to verify the integrity of the received frame
B. to verify the physical address in the frame
C. to verify the logical address in the frame
D. to compute the checksum header for the data field in the frame
Answer: A
What is contained in the trailer of a data-link frame?
A. logical address
B. physical address
C. data
D. error detection
Answer: D
Which statement describes a characteristic of the frame header fields of the data link layer?
A. They all include the flow control and logical connection fields.
B. Ethernet frame header fields contain Layer 3 source and destination addresses.
C. They vary depending on protocols.
D. They include information on user applications.
Answer: C
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?
A. mesh
B. partial mesh
C. hub and spoke
D. point-to-point
Answer: B
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.)
A. auto-MDIX B. CEF C. Frame Check Sequence D. minimum frame size E. source MAC address
Answer: CD
Which media communication type does not require media arbitration in the data link layer?
A. deterministic
B. half-duplex
C. full-duplex
D. controlled access
Answer: C
Which statement describes an extended star topology?
A. End devices connect to a central intermediate device, which in turn connects to other central intermediate devices.
B. End devices are connected together by a bus and each bus connects to a central intermediate device.
C. Each end system is connected to its respective neighbor via an intermediate device.
D. All end and intermediate devices are connected in a chain to each other.
Answer: A
What is a characteristic of the LLC sublayer?
A. It provides the logical addressing required that identifies the device.
B. It provides delimitation of data according to the physical signaling requirements of the medium.
C. It places information in the frame allowing multiple Layer 3 protocols to use the same network interface and media.
D. It defines software processes that provide services to the physical layer.
Answer: C
What are three ways that media access control is used in networking? (Choose three.)
A. Ethernet utilizes CSMA/CD.
B. Media access control provides placement of data frames onto the media.
C. Contention-based access is also known as deterministic.
D. 802.11 utilizes CSMA/CD.
E. Data link layer protocols define the rules for access to different media.
F. Networks with controlled access have reduced performance due to data collisions.
Answer: BCE
During the encapsulation process, what occurs at the data link layer for a PC connected to an Ethernet network?
A. An IP address is added.
B. The logical address is added.
C. The physical address is added.
D. The process port number is added.
Answer: C
What three items are contained in an Ethernet header and trailer? (Choose three.)
A. source IP address B. source MAC address C. destination IP address D. destination MAC address E. error-checking information
Answer: BDE
What type of communication rule would best describe CSMA/CD?
A. access method
B. flow control
C. message encapsulation
D. message encoding
Answer: A
Which three basic parts are common to all frame types supported by the data link layer? (Choose three.)
A. header B. type field C. MTU size D. data E. trailer F. CRC value
Answer: ADE
Which statement is true about the CSMA/CD access method that is used in Ethernet?
A. When a device hears a carrier signal and transmits, a collision cannot occur.
B. A jamming signal causes only devices that caused the collision to execute a backoff algorithm.
C. All network devices must listen before transmitting.
D. Devices involved in a collision get priority to transmit after the backoff period.
Answer: C
What is the auto-MDIX feature on a switch?
A. the automatic configuration of an interface for 10/100/1000 Mb/s operation
B. the automatic configuration of an interface for a straight-through or a crossover Ethernet cable connection
C. the automatic configuration of full-duplex operation over a single Ethernet copper or optical cable
D. the ability to turn a switch interface on or off accordingly if an active connection is detected
Answer: B
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?
A. port-based buffering
B. level 1 cache buffering
C. shared memory buffering
D. fixed configuration buffering
Answer: C
What are two examples of the cut-through switching method? (Choose two.)
A. store-and-forward switching B. fast-forward switching C. CRC switching D. fragment-free switching E. QOS switching
Answer: BD
