Communication

Communication

benefits of networking computers and devices

• Users can share files and data

• Easy to backup the data

• easy to oversee what is happening in each device

• allows instant message sharing

• Allows sharing of the devices and hence reduces the cost.

• Licences to run the softwares are cheap compared to stand alone devices

Drawbacks of Networking

• Cabling and servers can be an expensive initial outlay.

• Managing a large network can be a complex and difficult task.

• A breakdown of devices, such as the file servers, can affect the whole network.

• Malware and hacking can affect entire networks (particularly if a LAN is part

  of a much larger WAN),

Private or public Networks.

• Private networks are owned by a single company or organisation (they are often LANs or intranets with restricted user access, for example, passwords and user ids are required to join the network)

• Public networks are owned by a communications carrier company (such as a telecoms company)

WANs VS LANs

Activity

• Discuss the key difference between WAN and LAN

• Mention the devices used in LAN and their uses.

• Explain what is meant by Wireless LAN and give the devices used in Wireless LAN

• Explain the meaning of WAN

• Explain the meaning of MAN

NOTE

The following is used as a guide for deciding the ‘size’ of a network:

• WAN: 100 km to over 1000 km

• MAN: 1 km to 100 km

• LAN: 10 m to 1000 m

• PAN: 1 m to 10 m

peer-to-peer

• Describe how it looks like

• Examples of use of the model

• what are the merits and drawbacks of it

client-server

Types of networking models

• Describe how it looks like

• Examples of use of the model

• What are the merits and drawbacks of it

• How do they works

• prons and cons

Thin clients

• How do they works

• prons and cons

Thick clients

Thick clients VS Thin clients

Thin Client VS Thick Client

The biggest and most obvious difference between the two is that thin clients rely on a network connection for computing and don't do much processing on the hardware itself. Thick clients don't need the constant network connection and can do much of the processing for client/server applications.

Thin Client VS Thick Client

The biggest and most obvious difference between the two is that thin clients rely on a network connection for computing and don't do much processing on the hardware itself. Thick clients don't need the constant network connection and can do much of the processing for client/server applications.

Homework

A company has 20 employees working on the development of a new type of battery for use in mobile phones. Decide which type of network model (client-server or peer-to-peer) would be most suitable. Give reasons for your choice.

Multiple Choice

What is a primary characteristic of a thin client architecture?

• Heavy reliance on local processing power

• Centralized processing on a server

• High resource requirements on client devices

• Extensive use of thick client applications

Multiple Choice

In a thin client environment, where is most of the processing and application logic executed?

• CPU

• Server

• Network

• None

Multiple Choice

What type of client is more suitable for resource-intensive applications like video editing or 3D gaming?

• Thin client

• Thick client

• Both are equally suitable

• Neither is suitable for resource-intensive tasks

Multiple Choice

Which client type offers better security in terms of data protection?

• Thin client

• Thick client

• Both offer similar security

• Neither offers data protection

Multiple Choice

What is a potential disadvantage of thin client architecture in areas with unreliable or slow internet connections?

• Improved accessibility

• Reduced latency

• Limited usability

• Enhanced offline capabilities

Multiple Choice

Which client type is more suitable for resource-intensive applications like video editing or 3D gaming?

• Thin client

• Thick client

• Both are equally suitable

• Neither is suitable

Multiple Choice

What is a primary advantage of thin clients in terms of software maintenance?

• Centralized updates and easier version control

• Reduced network latency

• Greater offline functionality

• Enhanced graphical performance

Multiple Choice

In a thin client architecture, how are applications typically delivered to client devices?

• Locally installed on each device

• Streamed or accessed via a web browser

• Through physical media (e.g., CDs)

• Downloaded from a peer-to-peer network

Public and private cloud computing

Cloud storage is a method of data storage where data is stored on offsite servers – the physical storage covers hundreds of servers in many locations.
There are three common systems
Public Cloud : is a storage environment where the customer/client and cloud

storage provider are different companies.
Private Cloud: is storage provided by a dedicated environment behind a

company firewall.
Hybrid Cloud: is a combination of private and public clouds.

• Difficult to access files when there is unstable internet

• Expensive for large storage

• Expensive for downloading large files

​Cons

• files can be accessed anywhere

• No need for external devices.

• Easy for backup

• Offers almost unlimited storage

​Pros

Pros and Cons of Cloud Storage

Wired and wireless networking

Wireless

Both Wi-Fi and Bluetooth offer wireless communication between devices. They both use electromagnetic radiation as the carrier of data transmission.
Bluetooth is useful when
1. transferring data between two or more devices which are less than 30

metres apart
2. the speed of data transmission is not critical
3. using low bandwidth applications (for example, sending music files from a

mobile phone to a headset).

Wired Networking

There are three main types of cable used in wired networks
1. Twisted pair cable
2. Coaxial cable and
3. fibre optic cable
YouTube Video explaining the types of cables. https://www.youtube.com/watch?v=fgOkvIHKgXQ

1. It is easier to expand networks and is not necessary to connect devices using cables.

2. Devices have increased mobility, provided they are within range of the WAPs.

3. Increased chance of interference from external sources.

4. Data is less secure than with wired systems

5. Data transmission rate is slower than wired networks

6. Signals can be stopped by thick walls and signal strength can vary, or ‘drop out’.

Wireless networking

1. More reliable and stable network

2. Data transfer rates tend to be faster with no ‘dead spots’.

3. Tends to be cheaper overall, in spite of the need to buy and install cable.

4. Devices are not mobile; they must be close enough to allow for cable connections.

5. Lots of wires can lead to tripping hazards, overheating of connections (potential fire risk) and disconnection of cables during routine office cleaning.

Wired networking

Multiple Choice

Which of the following is a characteristic of a wired network?

• High mobility

• Low reliability

• Physical cables

• Radio waves

Multiple Choice

In terms of data transfer speed, wired networks generally offer:

• Slower speeds than wireless networks

• Faster speeds than wireless networks

• Similar speeds to wireless networks

• Unpredictable speeds

Multiple Choice

Which type of network typically provides faster and more stable connections?

• Wireless Network
• Dial-up Network
• Mobile Network
• Wired Network

Multiple Choice

Which type of network is generally more susceptible to interference and signal loss?

• Wired Network
• Wireless Network
• Virtual Private Network (VPN)
• Local Area Network (LAN)

Multiple Choice

In a wired network, data is transmitted through:

• Radio waves
• Infrared waves
• Cables
• Bluetooth

Multiple Choice

What is the most common use of coaxial cables in communication systems?

• Ethernet networking

• Cable television (CATV)

• Telephone lines

• Fiber optics

Multiple Choice

Coaxial cables are known for their:

• High data transmission speed
• Ability to transmit over long distances
• Resistance to interference
• Low cost

Multiple Choice

What is the primary advantage of twisted pair cables in networking?

• They are cheaper than other types of cables
• They can transmit data at extremely high speeds
• They are resistant to electromagnetic interference
• They are easy to install and manage

Multiple Choice

In twisted pair cables, how are the pairs twisted together?

• They are twisted together in a clockwise direction
• They are twisted together in a counterclockwise direction
• They are twisted together in a random direction
• In opposite directions

Multiple Choice

What is the advantage of using fiber optic cables for data transmission?

• High bandwidth and immunity to EMI

• Low cost and easy installation

• Compatibility with older networking standards

• Resistance to physical damage

1. Hub: Hubs are hardware devices that can have a number of devices or computers connected to them.

2. Switch: Switches are similar to hubs, but are more efficient in the way they distribute the data packet. However, unlike a hub, the switch checks the data packet received and works out its destination address (or addresses) and sends the data to the appropriate computer(s) only.

Hardware requirements of networks

3. Repeater: are devices which are added to transmission systems to

   boost the signal so it can travel greater distances. Repeaters can also be used on wireless systems. These are used to boost

   signals to prevent any ‘dead spots’ in the Wi-Fi zone.

4. Bridge: are devices that connect one LAN to another LAN that uses the same protocol (communication rules). They are often used to connect together different parts of a LAN so that they can function as a single LAN.

Cont..

4. Router: Routers enable data packets to be routed between the different networks for example, to join a LAN to a WAN. The router takes data transmitted in one format from a network (which is using a particular protocol) and converts the data to a protocol and format understood by another network, thereby allowing them to communicate via the router.

Cont..

Homework

1. Identify two differences between a public IP address and a private IP address.

2. Identify the most appropriate term for each description. Each term must be different.

   1. Receives data packets from a network and forwards them onto a similar network.

   2. Manages access to a centralised resource

   3. Joins networks that use different sets of rules to transmit data

   4. Monitors and controls incoming and outgoing network traffic based on set criteria

Cont..

3. Networks can be either wired using cables or wireless using radio waves.

   1. Describe one benefit of using a wireless network compared to using a wired network.

   2. Describe two drawbacks of using a wireless network compared to using a wired network.