2.3 Internet principles

Question 1

Define the ‘internet’

Answer 1

A network of networks, often use of telephone networks to transfer data between networks.

Question 2

Who invented ‘WWW’ and how does it work

Answer 2

• Tim Burners-Lee
• World Wide Web
• Webpages (HTML)
• Lookup domain name service (DNS)
• Hyper text transfer protocol (HTTP)

Question 3

What does an ‘ISP’ do?

Answer 3

• Internet service provider
• Provides physical connectivity
• Provides a DNS

Question 4

What does a ‘modem’ do?

Answer 4

• Modulator/demodulator
• Changes the frequency of a computers digital signal into analogue signal so that it can be send using telephone lines
• A second modem at the receiving end turns the analogue signal back into digital for the computer to understand

Question 5

What does a ‘router’ do?

Answer 5

• Directs traffic between different networks

- Connects several computers/other devices to a single internet connection in a home network

Question 6

What is an ‘IP Address’?

Answer 6

• A dotted-decimal notation
• A 32-bit adress
• Made of 4 separate 8-bit numbers (IP V.4)

Question 7

What is a Transmission Control Protocol

Answer 7

• TCP
• Breaks up messages/information sent over the internet into chunks called packets
• Reassembles the packets at the other end
• Detects erros
• Resends the packets with errors in them

Question 8

What is ‘IP Protocol’

Answer 8

-Routes individual packets separately between the sender and the recipient

Question 9

IP v.4 Class C example

Answer 9

eg. 192.144.247.12:
- 192.144.247 = network
- .12 = host (your computer)
- 247.12 = private range (each have 255 possible values which means that there are 65,000 addresses in the private range)

Question 10

What is a ‘gateway’?

Answer 10

A computer system that links two dissimilar computer networks

Question 11

What is a ‘MAC Address’?

Answer 11

• Media Address Control
• Provides a geographical location of the device determined by the IP
• The MAC address will change if you connect the same computer to the internet at your neighbours house
• When accessing a website, each router along the way uses the MAC Address to determine where to send the each packet of information next
• The MAC Address of a NIC never changes

Question 12

What is a ‘NIC’?

Answer 12

• A Network Interface Card
• Built into every networked device
• Can be wired or wireless

Question 13

Break down of a URL

Answer 13

-Universe Resource Locator
-www.miles.co.uk/images/logo.png:
www. = hosted on the world wide web
miles. = organisation name
co. = it’s a company
uk = it’s UK based
/images = folder location
/logo.png = the specific file name