Chapter 1.2: Exploring the Network: LANs, WANs, and the Internet (inc)

Question 1

In a network infrastructure what are three categories of network components?
1.2.1.1

Answer 1

• Devices
• Media
• Services

Question 2

What is the simplest path that a message can take from a source to a destination?
1.2.1.1

Answer 2

The simplest path a message can take is through one cable from one computer to another.

Question 3

What are the physical elements in a network infrastructure? Give examples.
1.2.1.1

Answer 3

Devices and media are the physical elements, or hardware, of the network.

Devices are things like servers, routers switches, wireless access points.

Media are the connections (chords and plugs?)

Question 4

In a network infrastructure, what are services?

1.2.1.1

Answer 4

Services are software and processes that run on network devices.

Examples include email hosting and webhosting services and processes that provide the functionality that directs and moves the messages through the network.

Question 5

What is the difference between a service and a process?

Answer 5

http://superuser.com/questions/209654/whats-the-difference-between-an-application-process-and-services

Question 6

What are end devices?

1.2.1.2

Answer 6

They are hosts that form the interface between users and the underlying communication network.

Question 7

Where does data originate and end?

1.2.1.2

Answer 7

Data originates with an end device, flows through the network, and arrives at an end device.

Question 8

List some end devices.

1.2.1.2

Answer 8

-Computers (workstations, laptops, file servers, web servers)
-Network Printers
-VoIP phones
-TelePresence endpoint
Security cameras
-Mobile handheld devices (Phones, tablets, PDA, wireless debit/credit card readers and barcode scanners.)

Question 9

How do hosts distinguish between one another?

1.2.1.2

Answer 9

Each host is identified by an address.

Question 10

What happens when a host wants to communicate with another host?
1.2.1.2

Answer 10

The host initiates the communication using the address of the destination host to specify where the message should be sent.

Question 11

What are Intermediary devices?

1.2.1.3

Answer 11

Intermediary devices are devices that interconnect end devices.

They provide connectivity and work behind the scenes to ensure that data flows across the network. They connect individual hosts to the network and can connect multiple individual networks to form an internetwork.

Question 12

What do Intermediary devices do?

1.2.1.3

Answer 12

They provide connectivity and work behind the scenes to ensure that data flows across the network. They connect individual hosts to the network and can connect multiple individual networks to form an internetwork.

Question 13

List examples of intermediary network devices.

1.2.1.3

Answer 13

• Network Access (switches and wireless access points)
• Internetworking (routers)
• Security (firewalls)

Question 14

What is the role of intermediary devices?

1.2.1.3

Answer 14

The role of an intermediary device is to manage data as it flows through the network. The devices use the destination host address, in conjunction with information about the network interconnections, to determine the path that messages should take through the network.

Question 15

What functions do the processes running on intermediary network devices perform?
1.2.1.3

Answer 15

• Regenerate and retransmit data signals
• Maintain information about what pathways exist through the network and internetwork
• Notify other devices of errors and communication failures
• Direct data along alternate pathways when there is a link failure
• Classify and direct messages according to Quality of Service (QoS) priorities
• Permit or deny the flow of data based on security settings.