IP, MAC, Packets and Protocols

Question 1

Define IP (Internet Protocol) Address.

Answer 1

A 32-bit number separated into 4 8-bit sections between 1 and 255, separated by dots.

Question 2

Which address will change depending on what network you are connected to?

Answer 2

IP Address.

Question 3

What is the MAC address?

Answer 3

A number which is permanently assigned to the wireless adapter. When a computer connects to a network, the computer broadcasts its MAC address to the router, which then assigns it an IP address.

Question 4

What does MAC stand for?

Answer 4

Media Access Control.

Question 5

What is a packet and what does it contain?

Answer 5

A small section of a file which contains: part of the file, the IP addresses of the sender and the recipient and a checksum. These packets are reassembled into the file at the end.

Question 6

What benefit does splitting files into packets give?

Answer 6

The network can spread the packets across the whole network, increasing speeds and not overloading parts.

Question 7

Define protocol.

Answer 7

A set of rules which governs the transmission of data. This tells a computer how big packets to send and what happens if transmission goes wrong.

Question 8

What is the most common protocol?

Answer 8

TCP.

Question 9

What is the purpose of a checksum?

Answer 9

To govern if the file has reached its recipient.

Question 10

What is a static IP address and what is its purpose?

Answer 10

It is an IP address of a server which stays the same so it can always be found.

Question 11

What is a dynamic IP address?

Answer 11

An IP address (usually of a small network) that changes, and that doesn’t matter if it does.

Question 12

Why are domain names used instead of IP addresses?

Answer 12

To make it more convenient (e.g. google.co.uk instead of a 32-bit number).

Question 13

Of the domain name “google.co.uk”, what is the top-level domain and what does this tell us?

Answer 13

“uk”. In this case it tells us the country of which the server is usually in, and where the website comes from.

Question 14

Of the domain name “google.co.uk”, what is the middle-level domain and what does this tell us?

Answer 14

“co”. This means it is a corporation.

Question 15

Of the domain name “google.co.uk”, what is the lowest-level domain and what does this tell us?

Answer 15

“google”. This gives us the company name.

Question 16

Why do we use the DNS (Domain Name System)?

Answer 16

To tell a computer which domain name matches which static IP address.

Question 17

Individual domain names have individual ___.

Answer 17

Servers.

Question 18

What is the authoritative server of a website?

Answer 18

A server set by the website owner which is usually the most reliable source to find the static IP address that relates to the domain name.

Question 19

How can we access a “WHOIS” tool and what will it tell us?

Answer 19

It can be accessed in a Nominet website. It tells us the list of authoritative name servers in a domain (like google.co.uk).

Question 20

Why are 32-bit IP addresses now a limitation?

Answer 20

They give us around 4 billion possible IP addresses, which is not enough.

Question 21

How many bits and possibilities does IPv6 give us?

Answer 21

128 bits give us 3.4x10³⁸possibilities - this will last a long time.

Question 22

What do internet-connected routers have?

Answer 22

Public DCHPs (Dynamic Host Configuration Protocol), which can assign ports and dynamic IP addresses to computers.