Chapter 4: Network Access

What makes fiber preferable to copper cabling for interconnecting buildings? (Choose three.)

1) **Greater distances per cable run 2) Lower installation cost 3) **Limited susceptibility to EMI/RFI 4) Durable connections 5) **Greater bandwidth potential 6) Easily terminated

Which two factors influence the method that is used for media access control? (Choose two.)

1) **How the connection between nodes appears to the data link layer 2) How data is generated by end devices applications 3) How signals are encoded by the NICs on end devices​ 4) **How the nodes share the media 5) How the IP protocol forwards the packet to the destination

What are two characteristics of 802.11 wireless networks? (Choose two.)

1) **They use CSMA/CA technology. 2) They use CSMA/CD technology. 3) They are collision-free networks. 4) Stations can transmit at any time. 5) **Collisions can exist in the networks.

A network administrator is designing the layout of a new wireless network. Which three areas of concern should be accounted for when building a wireless network? (Choose three.)

1) Coverage area 2) Interference 30 Security

A network administrator notices that some newly installed Ethernet cabling is carrying corrupt and distorted data signals. The new cabling was installed in the ceiling close to fluorescent lights and electrical equipment. Which two factors may interfere with the copper cabling and result in signal distortion and data corruption? (Choose two.)

1) EMI 2) RFI

Which statement is correct about multimode fiber?

1) Multimode fiber cables carry signals from multiple connected sending devices. 2) Multimode fiber commonly uses a laser as a light source. 3) *SC-SC patch cords are used with multimode fiber cables.* 4) Multimode fiber has a thinner core than single-mode fiber..

What are two reasons for physical layer protocols to use frame encoding techniques? (Choose two.)

1) To distinguish data bits from control bits 2) To identify where the frame starts and ends

A network administrator is designing the layout of a new wireless network. Which three areas of concern should be accounted for when building a wireless network? (Choose three.)

1) mobility options 2) *security 3) *interference 4) *coverage area 5) extensive cabling 6) packet collision

Fill in the blank with a number. 10,000,000,000 b/s can also be written as ______________ Gb/s.

10

The throughput of a FastEthernet network is 80 Mb/s. The traffic overhead for establishing sessions, acknowledgments, and encapsulation is 15 Mb/s for the same time period. What is the goodput for this network?

65 Mb/s

A network administrator is required to upgrade wireless access to end users in a building. To provide data rates up to 1.3 Gb/s and still be backward compatible with older devices, which wireless standard should be implemented?

802.11ac

How is the magnetic field cancellation effect enhanced in UTP cables?

By increasing and varying the number of twists in each wire pair

What method is used to manage contention-based access on a wireless network?

CSMA/CA

Which statement correctly describes frame encoding?

It converts bits into a predefined code in order to provide a predictable pattern to help distinguish data bits from control bits.

What is one advantage of using fiber optic cabling rather than copper cabling?

It is able to carry signals much farther than copper cabling.

What is one main characteristic of the data link layer?

It shields the upper layer protocol from being aware of the physical medium to be used in the communication.

Fill in the blank. What acronym is used to reference the data link sublayer that identifies the network layer protocol encapsulated in the frame? _____________________________

LLC

What is true concerning physical and logical topologies?

Logical topologies determine the media access control method used.

Which statement describes signaling at the physical layer?

Sending the signals asynchronously means that they are transmitted without a clock signal.

What is a characteristic of a WAN hub-and-spoke topology?

The branch sites are connected to a central site through point-to-point links.​

A network administrator is designing a new network infrastructure that includes both wired and wireless connectivity. Under which situation would a wireless connection be recommended?

The end-user device needs mobility when connecting to the network.

As data travels on the media in a stream of 1s and 0s how does a receiving node identify the beginning and end of a frame??

The transmitting node inserts start and stop bits into the frame.

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

They allow for full-duplex connectivity.

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

They vary depending on protocols.

Fill in the blank. The term ______________________________ indicates the capacity of a medium to carry data and it is typically measured in kilobits per second (kb/s) or megabits per second (Mb/s).?

bandwidth

Which layer of the OSI model is responsible for specifying the encapsulation method used for specific types of media?

data-link

Fill in the blank. In fiber optic media, the signals are represented as patterns of _________________________________

light

Which method of data transfer allows information to be sent and received at the same time?

multiplex

What type of cable is used to connect a workstation serial port to a Cisco router console port?

rollover

Which is a function of the Logical Link Control (LLC) sublayer?

to identify which network layer protocol is being used

What is the purpose of the OSI physical layer?

transmitting bits across the local media