Guided and Unguided Network Systems

In your previous sections, you have seen how a network plays a vital role in connecting people, devices and information. To make these connections possible, several network devices are used. These devices help in transmitting, directing and managing data within a network. For example, when you connect to the internet using a phone or computer, devices like routers, switches and modems make this possible. Understanding how these devices work is important for you as a learner, especially in a technology- driven society like ours. In this section, you will explore some commonly used network devices, their functions and how they help create and manage computer networks.

This knowledge will help you understand how data travels from one device to another and how networks operate in schools, offices and homes.

KEY IDEAS

• Definition of network devices: What network devices are and their role in data communication.

• Differences among devices: Comparing devices based on their roles and how they operate.

• Functions of each device: Exploring how each device supports communication within a network.

• Practical Examples: Observing how these devices are used in real-world settings like homes, schools and offices.

• Types of commonly used network devices: Identifying key devices such as routers, switches, hubs, modems and access points.

• Wired vs. wireless devices: Understanding how connectivity types affect device use.

Activity 5.1 Tracing the digital path This activity will start with your past knowledge on how websites are accessed and how network communication works, in order to understand the devices that make these connections possible.

1. How do you access a website like www.google.com from your device?

2. List some key elements involved in navigating a website (e.g., hyperlinks, internet, etc)

3. Draw a simple diagram of a device (e.g., smartphone or computer) accessing a website and suggest what components are involved in making this happen.

4. What does TCP/IP stand for?

5. How is data sent across a network?

6. What devices must be present for a school to connect all its computers to the internet?

Commonly used network devices A network device is a hardware or software component that allows computers and other electronic devices to connect to a network and exchange information. These devices help control the flow of data, ensure network security, and support the sharing of resources such as printers and internet access. Common examples of these devices include: broadband, modems, wireless access points, routers, pfSense, Cisco Packet Tracer, hubs and switches.

Broadband devices Broadband devices allow multiple users to connect to the internet at the same time and enjoy faster speeds for activities like browsing, streaming, downloading and online learning. Examples include; Modems, broadband routers and fibre optic terminals.

Modem (Modulator-Demodulator) A modem is essential for converting digital data from your computer into signals that can travel through phone lines, fibre-optic cables or cable systems. There are various types of modems, each with its own advantages.

Figure 5.1: Modem

Types of Modems

1. DSL Modem: Connects to a phone line Advantages

a. Availability: Widely available and used in areas with existing phone lines.

b. Speed: Good for typical home usage, such as browsing and streaming in standard definition.

c. Affordability: Generally, less expensive compared to other types of modems.

2. Cable Modem: Connects to a TV cable Advantages

a. Faster Speeds: Offers higher speeds than DSL modems, making it suitable for

activities like HD video streaming, gaming and downloading large files.

b. More Reliable: More reliable for households or offices needing a constant internet connection.

c. Availability: Best suited for areas with cable TV infrastructure.

3. Fibre Modem: Connects to fibre-optic internet Advantages

a. Super-Fast Speeds: Fibre-optic modems provide the fastest internet speeds, making them ideal for high-demand activities like 4K video streaming, cloud computing and large file transfers.

b. Future-Proof: As fibre technology improves, it can handle increasingly high internet usage.

c. Low Latency: Fibre internet tends to have low latency, which improves online gaming and real-time applications.

Figure 5.2: Modem Type Comparison

Router A router connects multiple devices to the internet through a modem and directs the data traffic between them. It comes in different forms and functionalities depending on the needs of the network.

Figure 5.3: Routers

Types of Routers

1. Wired Routers

Advantages

a. Stable Connection: Wired connections are more stable than wireless, offering less interference.

b. Security: More secure as data is transmitted via physical cables, reducing the risk of eavesdropping.

c. Speed: Wired connections typically provide faster speeds compared to wireless connections.

2. Wireless Routers

Advantages

a. Convenience: Devices like smartphones, tablets and laptops can connect wirelessly, providing mobility within the home or office.

b. Multiple Device Support: They can handle a variety of devices at once without the need for physical connections.

c. Ease of Setup: Wireless routers are easy to set up and do not require cables, which makes them ideal for users who want simple installations.

3. Mesh Routers

Advantages

a. Wide Coverage: Mesh routers are perfect for larger homes or offices as they cover a bigger area by using multiple access points (nodes).

b. Seamless Connectivity: They provide a seamless connection as users move around, without having to switch networks.

c. Improved Speed and Performance: Better speed and performance over long distances, eliminating “dead zones” in the Wi-Fi coverage.

Figure 5.4: Router Types Comparison

Wireless Access Point (WAP)

A Wireless Access Point (WAP) is a networking hardware device that allows Wi-Fi enabled devices (like smartphones, laptops, tablets) to connect to a wired network.

Think of it as a central hub that broadcasts a wireless signal, enabling all nearby compatible devices to get online without needing physical cables.

Core Function

WAPs create a Wireless Local Area Network (WLAN), allowing devices to communicate wirelessly with each other and, crucially, to access the internet if the WAP is connected to a broadband router.

How it Works A WAP is typically connected via an Ethernet cable to a router (which brings the internet connection from an Internet Service Provider, ISP) or a network switch within an organisation.

Figure 5.5: Wireless Access Point (WAPs)

Types of WAPs

Integrated WAPs (in Home Routers)

This is the most common type of WAP a learner would encounter at home. Most standard home Wi-Fi routers (provided by ISPs like Telecel Broadband, MTN, AT or when you buy a general Wi-Fi router) have a built-in WAP function. These devices combine a router, a WAP and often a switch in one unit.

They provide Wi-Fi for all devices within a typical home or small office environment.

Advantages

a. Cost-Effective: Since they are integrated into home routers, they eliminate the need to buy a separate WAP.

b. Simplicity: Easy to set up, with fewer devices involved in the network setup.

c. Convenience: Provides Wi-Fi coverage for a typical home without the need for additional equipment.

Standalone WAPs

These are dedicated devices solely designed to provide Wi-Fi access. They do not have routing capabilities themselves but connect to an existing router or network.

Often found in larger settings like schools, universities, hotels or large businesses.

Multiple standalone WAPs are strategically placed to ensure strong Wi-Fi coverage across many rooms or large areas.

Figure 5.6: Standalone WAP

Advantages

a. Stronger Coverage: Used in larger settings like schools, hotels and businesses.

They provide better coverage for larger areas compared to integrated WAPs.

b. Flexibility: Can be installed in specific locations to extend Wi-Fi coverage in areas that integrated routers cannot reach.

c. Scalability: More WAPs can be added to extend coverage without interfering with network performance.

Mesh Wi-Fi Systems

These involve multiple WAPs (often called ‘nodes’ or ‘points’) that work together to create a single, all-in-one Wi-Fi network across a larger area. They communicate with each other to extend coverage and improve signal strength.

Increasingly used in larger homes or educational institutions to eliminate Wi-Fi dead zones and provide consistent coverage throughout a building.

Figure 5.7: Mesh Wi-Fi Systems

Advantages

a. Continuous Coverage: These systems ensure consistent Wi-Fi coverage across larger homes or organisations by using multiple access points that work together.

b. No Interruption: Users experience no interruptions as they move between rooms or buildings, ensuring a smooth experience.

c. High Performance: Mesh systems can handle high traffic and multiple devices, ensuring fast and reliable speeds.

Figure 5.8 Advantages of WAP Types

Switch A switch is a network device that connects multiple computers or devices in a network and helps them share information smoothly. It checks each data packet for errors before sending it to the right device. If the data has a problem, the switch does not send it. If the data is correct, the switch sends it only to the device it is meant for, not to all devices. This makes communication faster and more efficient. A switch also helps reduce data traffic between devices by creating a separate path for each connection, but all devices still receive general messages sent to everyone on the network.

Figure 5.9: Switch

Table 5.1: Types of Switches

S/N TYPE OF

SWITCH DESCRIPTION ADVANTAGES DIAGRAM

1 Unmanaged Switches

Simple plug-and- play switches with no advanced configuration options. Suitable for small networks or as an expansion.

Plug-and-Play: No

setup required.

Affordable: Ideal for

small networks. Low Maintenance: Minimal upkeep required.

2 Managed Switches

Switches with

advanced configuration options like VLANs, QoS, and link aggregation are used for larger networks.

Advanced Configuration: Supports

VLANs and QoS.

Network Control:

Full control over traffic management.

Scalability: Ideal for

large networks.

3 Smart Switches

Switches offering some features of managed switches but easier to set up. Best for small-to-medium networks.

Balance of Features:

Advanced features with easy setup.

Cost-Effective: Ideal

for medium-sized businesses.

4 Layer 2 Switches

Operates at

the Data Link Layer (Layer 2), forwarding data based on MAC addresses in a local network.

Simple and Fast:

Faster due to Layer 2 processing. Efficient for LANs: Great for small networks. Reduced Collisions: Separate collision domains for each device.

5 Layer 3 Switches

Operates at the

Network Layer

(Layer 3), routing traffic between different network segments or subnets.

Routing Capabilities:

Routes traffic between subnets. Improved Efficiency: Reduces the need for separate routers. Scalability:

Ideal for larger, complex networks.

6 PoE Switches

Allows power and data to be transmitted over the same Ethernet cable to devices like IP cameras or phones.

Simplifies Wiring:

Reduces the need for separate cables.

Cost-Efficient: Lowers

installation costs.

Convenience for Remote

Locations: Ideal for

hard-to-reach places.

7 Gigabit Switches

Supports Gigabit

Ethernet speeds (1 Gbps), essential for high-speed data transfer in modern networks.

High-Speed Data

Transfer: Ideal for high- bandwidth applications.

Future-Proofing:

Provides sufficient bandwidth for growing networks. Improved Performance: Reduces network bottlenecks.

8 Rack- Mounted

Switches Designed to

be mounted in server racks, ideal for large setups like data centres or enterprise networks.

Space-Saving: Saves

floor space in large environments.

Centralised Management: Easy

access for maintenance.

Scalability: Can be expanded easily.

9 Desktop Switches

Compact switches for small networks like offices or home use, often placed on desks or tables.

Compact and

Affordable: Great

for smaller setups.

Portability: Easy to

move and flexible. Basic Functionality: Ideal for small networks.

10 Modular Switches

Switches with modular components that can be added or removed to customise the switch based on network needs.

Customisable: Tailored

to specific network needs. Scalable:

Expands easily as the network grows. Future- Proof: Modules can be upgraded.

Figure 5.10: Switch Types Advantages

Hub A hub is a basic networking device used to connect multiple devices within a network.

It sends data to all devices connected to it, which can lead to inefficiency and slower speeds. It is also a significant security concern and, as such, would not typically be found installed in a modern network.

Figure 5.11: Hub

Table 5.2: Types of Hubs

S/N HUB TYPE DIAGRAM

1 Active Hub

2 Passive Hub

3 Intelligent Hub

Figure 5.12: Advantages of Hub Types

MiFi (Mobile Wi-Fi Hotspot)

These are small, portable wireless devices that act as a personal Wi-Fi hotspot. They use a SIM card to connect to a cellular network (like a smartphone) and then broadcast a Wi-Fi signal, allowing multiple devices (laptops, tablets, other smartphones) to connect to the internet simultaneously.

It is good for learners learning online, in homes without fibre or fixed broadband.

Popular brands in Ghana: MTN Mifi, Telecel MiFi, AirtelTigo Pocket WiFi

Figure 5.13: Samples of MiFi used in Ghana Smartphones (as Hotspots) For many Ghanaian learners, their smartphone is their primary and often only device for accessing the internet. These are versatile devices that combine a phone, a mini- computer and an internet access point.

Most smartphones can share their mobile data by creating a Wi-Fi personal hotspot.

It is handy for students in areas without routers or modems and provides the quickest way to connect a laptop to mobile internet. Your phone can also act as a mini-MiFi device.

Activity 5.2 Exploring Networking Devices and Their Applications

This activity will deepen your understanding of key networking devices such as broadband, modems, wireless access points, etc.

1. Organise yourself into a group of 3 to 4 people.

2. Discuss the uses of the following networking devices.

a. Broadband

b. Modems

c. Wireless Access Points

d. Routers

e. Network Cards

f. Hubs

g. Switches

3. Discuss how these devices work together to establish and maintain a network connection. Example:

a. What role does each device play in ensuring all-in-one connectivity and communication in a network?

b. How do modems and routers differ in their roles in connecting to the internet?

c. What is the significance of network cards in connecting devices to a network?

4. Identify and list the advantages and disadvantages of each device, focusing on their applications in different network setups in the table below.

S/N Device Advantages Disadvantages

1 Broadband 2 Hub

3 Switch 4 Modem

5 WAP 6 Network Card

7 Router

5. Present your findings in point 3 above to the class.

6. Reflect on what you learned from the other groups focusing on

a. The clarity of their explanation.

b. The accuracy of the information shared.

c. How well they differentiated between the devices and applied them to real-life situations.