Chapter 4

In fiber optic media, the signals are represented as patterns of .... .

light

fibre-optic

Advantages: Not affected by EMI or RFI Suitable for long distance Faster than copper Disadvantages: More expensive than copper Special skills and equipment required to install Used for backbone and long haul networks Bits represented as patterns of light, generated by either laser(Single-mode finer) or LEDs (Multimode fiber). Optical fiber is composed of two kinds of glass (core and cladding) and a protective outer shield (jacket).

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

CSMA/CA

How do you define the maximum possible throughput between the PC and the server?

The maximum throughput between any two nodes on a network is determined by the slowest link between those nodes.

Types of UTP Cable

Ethernet Straight-through: The most common type of networking cable. It is commonly used to interconnect a host to a switch and a switch to a router. Ethernet Crossover: A cable used to interconnect similar devices. For example to connect a switch to a switch, a host to a host, or a router to a router. Rollover: A Cisco proprietary cable used to connect a workstation to a router or switch console port.

What is the purpose of the OSI data link layer?

Exchanging frames, controlling media access, and performing error detection. The data link layer accepts Layer 3 packets and packages them into data units that are called frames.

Throughput

Factors that affect throughput are: Amount of traffic Type of traffic Latency caused by the number of network devices between the source and destination

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.

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

LLC = the MAC sublayer. LLC identifies which network layer protocol is being used

copper

Signals are electrical pulses. Advantages: Cheap, Easy to install and Low resistance to electrical current. Disadvantages: Limited by distance, Affected by electrical and radio interference (EMI and RFI)

UTP Cabling Standards

Speeds supported Cat 5(known as Fast Ethernet) - 100 Mb/s Cat 5e - 1000 Mb/s Cat 6 (recommended for new building installations) - 1000Mbs - 10 Gb/s

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.

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

They vary depending on protocols.

error detection

This field checks if the frame has been damaged during the transfer.

addressing

This field helps to direct the frame toward its destination.

frame start

This field identifies the beginning of a frame.

type

This field is used by the LLC to identify the Layer 3 protocol.

STP

This type of copper media is used in industrial or similar environments where there is a lot of interference.

optical fiber

This type of media is used for high transmission speed and can also transfer data over long distances.

coaxial

Traditionally used for television but can now be used in a network to connect the customer location to the wiring of the customer premises.

copper media types

UTP, STP, Coaxial

wireless

Uses radio or microwave frequencies. Advantages: Provides greatest mobility Disadvantages: Limited coverage area Susceptible to interference Users share the bandwidth

UTP

most common copper. unshielded twister pair. 4 colours. limit crosstalk by cancellation(wires are paired to cancel out EMI and RFI interference) and Varying the number of twists per wire pair (each pair of wires has a different number of twists .

wireless

best mobility option

A network team is comparing topologies for connecting on a shared media. Which physical topology is an example of a hybrid topology for a LAN?

extended star

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

full duplex

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

greater distances per cable run, limited susceptibility to EMI/RFI and greater bandwidth potential

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

how the connection between nodes appears to the data link layer ,how nodes share the media

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

rollover or console cable

What is the purpose of the OSI physical layer?

transmitting bits across the local media