Communications

Question 1

Networking Devices

Answer 1

Devices that enable fast data transmission within a network

Question 2

3 Networking Benefits:

Answer 2

1. File Sharing: Easy to share data between different interconnected devices
2. Resource Sharing: Use network-connected output devices like printers or share software within a network
3. Higher Storage: Files can be stored on network connected storage mediums.

Question 3

What is LAN

Answer 3

Local Area Network

Question 4

What is WAN

Answer 4

Wide Area Network

Question 5

Characteristics of LAN

Answer 5

A network that connects devices within a small geographical area, often within the same building.

Only private ownership.

Transmission medium: Twisted Pair Cables , Coaxial Cables or Wi-Fi.

Higher data transfer rate.

Less congestion.

Question 6

Characteristics of WAN

Answer 6

A network that connects devices within a larger geographical area, such as a city, country, or globally.

Private or public ownership.

Transmission medium: PSTN or Satlink.

Lower data transfer rate.

Higher Congestion

Question 7

Client Server Model

Answer 7

Server based network: A dedicated server provides applications for the client computer to utilise

Question 8

Applications of Client Server Models

Answer 8

Printer

File Sharing

Proxy Server

Database Server

(More…)

Question 9

What are Thin Clients

Answer 9

A client that solely runs on the resources provided by the server and has no local storage

Question 10

What are Think Clients

Answer 10

An Independent client that does not require the server to run

Question 11

3 Other differences between Thin and Thick Clients

Answer 11

Question 12

P2P model: Define and give examples

Answer 12

A centralised network where each connected computer stores data and operates independently as a ‘peer’, acting as both client and server

Examples: Internet and Ad hoc networks

Question 13

Differences between Client Server and P2P

Answer 13

Question 14

Differences between Client Server and P2P

Answer 14

Question 15

4 Types of Topology

Answer 15

Bus
Star
Mesh
Hybrid

Question 16

Wired Network Recap
(Should Know from the other set)

Answer 16

2 (3) Types: Copper Wires (Twisted Pair and Coexial Cable), Fibre optic

Cheapest -> Expensive
Twisted Pair, Coexial cable, Fibre Optic

Drawback of Copper Wires: Doesnt perform will with small charges; affected by electromagnets

Advantage of fiber optic: Greater bandwidth, improved security, light

Question 17

Wireless Network Recap
(Again should know from the other set)

Answer 17

Electromagnetic Waves
1. Radio Waves
2. Micro Waves
3. Satellies

Question 18

Ethernet.
Where is it commonly used.
How is it managed

Answer 18

Common in wired medium for LAN and WAN

Typically in Bus Topology.

Collisions are managed by the CSMA/CD method

Question 19

Describe the Steps of CSMA/CD
Hint: Theres 4

Answer 19

Device detects if the channel is busy before transmitting

If busy, the device waits a random time before retrying

During transmission: The device listens for other transmission

If a collision occurs, transmission aborted and (step 1 again) before retrying.

Question 20

Define Bit Streaming

Answer 20

Sequence of bits transferred over a communication path at high speeds. Requiring fast broadband connection and buffers

Question 21

2 types of bit streaming: Define and give an example

Answer 21

On demand: Pre-existing files are converted and streamed as requested (Youtube)

Real - Time: Live events captured and transmitted directly (Twitch)

Question 22

Why is fast broadband important in bit streaming

Answer 22

The user has to download and display bits at the
same time.

Higher quality media requires faster speeds due to larger data frames as well.

Real-time streaming needs higher speeds due to simultaneous data requests coming from multiple different users.

Question 23

Cloud Computing

Answer 23

On-demand provision of computing services over the internet, including infrastructure and platform.

Question 24

What is Infrastructure and Platform in Cloud Computing

Answer 24

Infrastructure: Storage capacity and higher processing power.

Platform: Software, testing & debugging resources.

Question 25

Public Cloud

Answer 25

Access Provided by third party service providers, shared among multiple users. Managed by cloud service providers using large server farms

Question 26

Private Cloud

Answer 26

Owned and maintained by a single organisation, providing exclusive access. Can be managed internally by the organisation itself or outsourced.

Question 27

Benefits and drawbacks of Cloud Computing

Answer 27

Question 28

World Wide Web (WWW). Description and Function

Answer 28

Description: Collection of web pages stored on websites Function: Protocols are used to transmit data across the WWW

Question 29

Internet - Description, Protocol, Access and Communication methods

Answer 29

Massive, open network of networks Protocol: Uses TCP/IP Protocol, which uses IP addresses to identify devices connected to the internet. Access: Provided by ISP Communication methods: Wired, radio and satellite

Question 30

Router - Function, Connections, Roles, Setup, IP translation

Answer 30

Function: Connects 2 networks together which operate under the same protocol. Connections: Allows internal connections between LANs or external between LAN and WAN Other Roles: Acts as a gateway or a firewall Setup: Usually attached to a server or switch in a LAN IP translation: Translate public IP to Private IP and vice versa

Question 31

The 8 LAN supporting Hardware

Answer 31

**Switch** - connect all devices to LAN **Server** - Device that provides specific functions for computers in the network **NIC** - Provide each end-system of a wired LAN with a unique MAC address **WNIC** - Provide each end-system of a wireless LAN with a unique network address **WAP** - Allows devices to connect to LAN via WIFI **Cables** - Wired transmission medium **Bridge** - Connect 2 LANs **Repeater** - Connect 2 cables

Question 32

IPv4

Answer 32

32 bit address split into 4 blocks by a “.” Each block can have a value up to 255 (8 bit block)

Question 33

IPv4 Structure

Answer 33

**NetID**: Identifies the network to the host device connected **HostID**: Identifies the host within the network **Classful Addressing**: Used for IPv4 where different bit length for identification impose restriction on available addresses

Question 34

IPv6

Answer 34

128 bit address divided into 8 blocks of 16 bit Each block can have 4 hex values from 0000 to FFFF IPv6 can be shortened by removing at least (≥) 2 blocks containing only zeroes. For example: “2001:0db8:85a3:0000:0000:8a2e:0070:7334” can be shortened to “2001:0db8:85a3::8a2e:0070:7334"

Question 35

Public IP address

Answer 35

Provided by the ISP Unique and can be accessed across the internet

Question 36

Private IP address

Answer 36

Issued by the LAN's router - Unique **within LAN** and **can only be accessed within LAN** NAT (Network Address Translation): Required for private IP addresses to access the internet directly Private IPs are more secure than public IPs as they are hidden by NAT Address Range: The range of IP addresses used for private IP addressing can never be assigned to public IP addresses

Question 37

Static VS Dynamic IP Addresses

Answer 37

Static: IP never change Dynamic: IP changes regularly

Question 38

Why use Static IP

Answer 38

They are valid when websites need to remember a device for a long time: VPN whitelisting Faster uploads/downloads

Question 39

Why use Dynamic IP

Answer 39

Dynamic IP is reletively more secure Cost of maintaining the dynamic IP address is lesser