1.3.3 - networks

Question 1

network

Answer 1

Two or more computers connected together to share info or resources.

Question 2

5 advantages of using a network

Answer 2

1- Users can share files.
2- Users can share resources like peripherals and Internet connection.
3- Users can access files from any computer on the network.
4- Servers can control security, software updates and backup of data.
5- Communication like email and social networking.

Question 3

4 disadvantages of using a network

Answer 3

1- Increased security risks to data.
2- Malware and viruses spread very easily between computers.
3- If a server fails, the computers connected to it may not work.
4- Computers may run slower if there is a lot of data travelling on the network.

Question 4

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

protocol

Answer 5

A set of rules defining common methods of data communication.

Question 6

transmission control protocol (TCP)

Answer 6

Provides error-free transmission between 2 routers.

Question 7

internet protocol (IP)

Answer 7

Routes packets across a WAN.

Question 8

user datagram protocol (UDP)

Answer 8

Uses a simple, connectionless transmission mode. Has no error checking and is used to send short messages.

Question 9

hypertext transfer protocol (HTTP)

Answer 9

A way for a client and server to send, receive, request and deliver HTML web pages.

Question 10

What makes HTTPS special?

Answer 10

Added encryption and authentication.

Question 11

file transfer protocol (FTP)

Answer 11

Used for sending files between computers, typically over a WAN.

Question 12

simple mail transfer protocol (SMTP)

Answer 12

Used to send emails and forward them from mail servers to their destination.

Question 13

post office protocol (POP)

Answer 13

Downloads email stored on a remote server to a local client, removing it from the server in the process.

Question 14

internet message access protocol

Answer 14

Manages emails on a server so multiple clients can access the same email account in synchronicity.

Question 15

modem

Answer 15

Transforms digital info from computer into analogue signals that can be transmitted through wires.

Question 16

router

Answer 16

Routes data between devices on a network and the internet.

Question 17

3 main types of wired connections

Answer 17

• twisted pair
• coaxial
• fibre optic

Question 18

What are twisted pair cables made up of?

Answer 18

A pair of insulated copper wires.

Question 19

advantage of twisted pair cables

Answer 19

More affordable than other options

Question 20

disadvantages of twisted pair cables

Answer 20

• Can be affected by noise from external magnetic fields.
• Can only provide low bandwidth.

Question 21

uses of twisted pair cables

Answer 21

• telephone networks
• data networks
• cable shielding

Question 22

What are coaxial cables made up of?

Answer 22

Made up of 4 cylindrical components:
1- a solid conductor wire
2- a layer of insulation
3- a grounding conductor wire
4- a layer of exterior insulation

Question 23

uses of coaxial cables

Answer 23

• computer network connections
• digital audio
• cable television

Question 24

What are fibre optic cables made up of?

Answer 24

Very thin optical fibres made of glass or plastic that are bundles together in a single cable.

Question 25

Why do fibre optic cables have the highest noise immunity?

Answer 25

The light rays are unaffected by electrical noise;

Question 26

Uses of fibre optic cables.

Answer 26

- long distance connections - data centres

Question 27

network interface controller (NIC)

Answer 27

Convert data signals from nodes into date signals that can be transferred across the network.

Question 28

wireless access point (WAP)

Answer 28

A device that creates a wireless LAN by connecting to a wired router, switch or hub using an Ethernet cable and projects a Wi-Fi signal within a designated area.

Question 29

hub

Answer 29

A device that connects multiple nodes together on one network. It broadcasts any transmissions it receives to all other connected devices even if it is not meant for them.

Question 30

switch

Answer 30

A device that connects multiple devices together on a network. Has software installed on it to inspect transmissions and route them to the correct device, keeping unnecessary traffic to a minimum.

Question 31

definition of the internet

Answer 31

A network of networks set up to allow computers to communicate with each other globally.

Question 32

world wide web

Answer 32

A collection of web pages that are stored on computers connected to the internet. It uses the internet as a service to communicate the info contained within these pages.

Question 33

Internet Service Providers (ISP)

Answer 33

Connect directly to backbone cables and distribute the internet connection to smaller providers who in turn, provide access to individual businesses and homes.

Question 34

uniform resource locator (url)

Answer 34

The full address of an internet resource.

Question 35

internet registrars

Answer 35

Hold records of all existing website names and the details of those domains that are currently available to purchase.

Question 36

domain name

Answer 36

Identifies the area or domain name that an Internet resource resides in.

Question 37

layering in protocols

Answer 37

Divides the complex task of networking into smaller, simpler tasks that work in tandem with each other. The hardware/software for each layer has a defined responsibility, and each one provides a service to the layer above it.

Question 38

3 advantages of layering in protocols

Answer 38

1- Reduces a complex problem into smaller sub-problems. 2- Devices can be manufactured to operate at a particular layer. 3- Products from different vendors will work together.

Question 39

4 layers of the TCP/IP stack

Answer 39

1- link 2- network 3- transport 4- application

Question 40

application layer of the TCP/IP stack

Answer 40

Used to provide services for applications that want to communicate across a network. Specifies the rules of what should be sent.

Question 41

transport layer of the TCP/IP stack

Answer 41

Uses the TCP as well as other conversion protocols like UDP to establish an end-to-end connections with the recipient computer. It splits the data into packets and adds the following info to them sequentially: 1- its number/ sequence 2- the total number of packets 3- the port number that the packet should use

Question 42

network layer of the TCP/IP stack

Answer 42

Uses the IP to address packets with: - Source IP address - Destination IP address

Question 43

link layer of the TCP/IP stack

Answer 43

Represents the actual physical connection between network devices. It is responsible for adding the unique MAC address of the source and destination device to the header.

Question 44

circuit switching

Answer 44

Creates a direct link between two devices for the duration of the communication.

Question 45

disadvantages of circuit switching

Answer 45

1- bandwidth is wasted during the periods when no data is being sent 2- can only connect devices that operate at the same transfer rate 3- electrical interference may corrupt data if the path is used to transfer data.

Question 46

advantage of circuit switching

Answer 46

Packets arrive in the same order that they were sent, simplifying the process of reconstructing the message at the recipient end.

Question 47

packet switching

Answer 47

A method of communicating packets of data across a network on which other similar communications are happening simultaneously.

Question 48

How is data corruption checked for in data packets?

Answer 48

The Cyclical Redundancy Check (CRC) is recalculated for each packet upon receipt and matched to ensure that the payload data has not changed during transmission.

Question 50

Time to live/ hop limit

Answer 50

After this point, the data packet expires and is discarded.