Section 1.3.3 Networks

Question 1

What is a network?

Answer 1

When a computing device is connected to another

Question 2

What are the advantages of networks? (5)

Answer 2

• Can share files
• Can share peripherals and connections to other networks e.g. the internet
• Can access files from any computer on the network
• Servers can control security, software updates and backups
• Good for collaborations

Question 3

What are the disadvantages of networks?

Answer 3

• Increased security risks
• Malware and viruses
• If the server fails, connections to it may not work
• Computer may run slower if there’s lots of data on the network

Question 4

What are standards?

Answer 4

A set of hardware and software specifications that allow manufacturers to create products and services that are compatible with each other

Question 5

What is a protocol?

Answer 5

A set of rules defining common methods of data communication

Question 6

What is the purpose of the TCP protocol?

Answer 6

Provides error free transmission between two routers

Question 7

What is the purpose of the IP protocol?

Answer 7

Routes packets across a WAN

Question 8

What is the purpose of the UDP (User Datagram Protocol) protocol?

Answer 8

Communication protocol for time sensitive applications e.g. gaming or DNS lookups

Question 9

What is the purpose of the HTTP protocol?

Answer 9

A way for the client and server to send and receive requests and deliver webpages

Question 10

What is the purpose of the HTTPS protocol?

Answer 10

A way for the client and server to send and receive requests and deliver webpages

Question 11

What is the purpose of the FTP protocol?

Answer 11

Used for sending files between computers (normally on a WAN)

Question 12

What is the purpose of the SMTP protocol?

Answer 12

Transfers outgoing emails between servers and from email clients to servers

Question 13

What is the purpose of the POP protocol?

Answer 13

Retrieves email from the mail server and transfers them to your device, removing them from the server

Question 14

What is the purpose of the IMAP (Internet Message Access Protocol) protocol?

Answer 14

Keeps emails on the mail server, maintaining synchronicity between devices

Question 15

What is the internet?

Answer 15

A collection of interconnected networks, routers, cables, satellites and other hardware spanning the world

Question 16

In a home network connected via a wireless router, what is the router connected to?

Answer 16

The ISP (connected by fibre optic cables or telephone connection
- ISP is then connected to the DNS and other routers

Question 17

What is layering?

Answer 17

Dividing the complex task of networking into smaller, simpler tasks that work in tandem with eachother

Question 18

What are the characteristics of layering?

Answer 18

• Hardware and software for each layer has a defined responsibility
• Each layer provides a service to the layer above it

Question 19

What are the advantages of layering?

Answer 19

• Reduces complexity of the task by dividing it into smaller subproblems
• Devices can be manufactured to operate at a particular layer
• Products from different vendors can work with eachother

Question 20

What is the TCP/IP stack?

Answer 20

Set of networking protocols, consisting of 4 protocols working together

Question 21

State the 4 layers in the TCP/IP protocol stack

Answer 21

• Application layer
• Transport layer
• Internet layer
• Link layer

Question 22

What is the purpose of the application layer?

Answer 22

Consists of protocol rules that deal with network applications e.g. web browsers and email programs

Question 23

What protocols are on the application layer?

Answer 23

• FTP
• HTTP
• HTTPS
• SMTP
• IMAP

Question 24

What’s the purpose of the transport layer?

Answer 24

Sets up communication between two hosts - agree on settings e.g. language

Question 25

What protocols are in the transport layer?

Answer 25

• TCP
• UDP

Question 26

What is the purpose of the internet layer?

Answer 26

Addresses and packages data for transmission / routes packets across a network

Question 27

What protocol is in the internet layer?

Answer 27

IP

Question 28

What is the purpose of the link layer?

Answer 28

Where net hardware and connections and OS drivers are located
- Facilitates transmission of binary via any media

Question 29

What happens in the application layer? (1/4)

Answer 29

Application uses the appropriate protocol relating to the application being used to transmit data

Question 30

What happens in the transport layer? (2/4)

Answer 30

• Uses TCP and other conversation protocols which use port numbers to track sessions and add it to the header
• When connection = made, TL splits data into packets
• Adds to each packet: its num./sequence, total num. of packets, port num. the packet should use

Question 31

What happens in the internet layer? (3/4)

Answer 31

• Packets go to the IL
• Adds to each packet: source IP address and destination IP address
• Routers use IP to find out where the packets are headed

Question 32

What happens in the link layer? (4/4)

Answer 32

• Acts as a physical connection in which the packets become frames
• Responsible for adding the MAC address of the source device and destination device

Question 33

What is an IP address?

Answer 33

A unique address hat identifies a device in the internet or a LAN