Lesson video

Hello, my name is Mrs. Holborow, and welcome to Computing.

I'm so pleased you could join me for the lesson today.

In today's lesson, you will be identifying the roles in a client-server network and describing the purpose of some common types of network.

For example, what is a PAN and what is it used for? Welcome to today's lesson from the unit, network fundamentals.

This lesson is called "Types of network." And by the end of today's lesson, you will be able to describe how devices operate in a client-server network and explain the purpose of different types of network.

Shall we make a start? We will be exploring these keywords throughout today's lesson.

Let's take a look at them now.

Client-server model.

Client-server model, a network where devices are designated as clients or servers.

Personal area network.

Personal area network, or PAN, a network of personal devices that allows data to be exchanged within their immediate vicinity.

Local area network.

Local area network, or LAN, a single network covering a single site, usually covering a small geographical area.

Wide area network.

Wide area network, or WAN, two or more distinct networks connected together, usually covering a large geographical area.

Look out for these keywords throughout today's lesson.

Today's lesson is broken down into two sections.

We'll start by identifying roles in a client-server network, and then we'll move on to describe the purpose of a PAN, LAN, and a WAN.

Let's make a start by identifying roles in a client-server network.

In the client-server model, there are two main roles.

One, the client, and two, the server.

Clients make requests.

This could be for all sorts of tasks, like requesting files, accessing emails, or printing a document.

Servers fulfil the requests from the client.

A server is a programme on a computer that shares resources with or provides services to any authorised client.

Most servers will run 24 hours a day, seven days a week, so that a client can send a request for resources at any time.

Time to check your understanding.

I have a true or false statement for you.

In the client-server model, the client's role is to fulfil requests made by the server.

Is this statement true or false? Pause the video whilst you think about your answer.

Did you say false? Well done.

But why is it false? The client makes requests for files or emails, and the server fulfils those requests.

A client is a programme that typically runs on a device used by an end user, such as a laptop or mobile phone.

A client sends a request to the server.

The server processes the request and then sends the response back to the client.

There are many different types of server.

Here are some that you should be aware of.

File servers store and provide files.

Web servers store and provide webpages.

Email servers store and forward emails.

Some email servers filter out spam.

Database servers store databases, run queries, and allow data to be manipulated.

Print servers provide printing services across the network and manage print queues.

There are lots of advantages of the client-server model.

Let's take a look at them now.

All of the files are stored on one central server.

All of the peripherals are processed via the server.

By peripheral, we mean something like a printer.

If a client machine breaks, it won't affect the whole network.

A backup can be taken of the server, rather than individual client machines.

There are some disadvantages of the client-server model.

They are typically expensive to set up compared to standalone computers or a peer-to-peer network.

A specialist network administrator is required to set up the network.

And if the server fails, everyone connected to the server is disrupted.

The client-server model is typically used where a central server is required.

For example, a business might need employees to share files and software.

These are stored and accessed via a central server to allow for shared access.

Online gaming sites often use a client-server model to provide shared access to an online environment.

All of the players access the gaming environment via the same server.

This allows them to play together on the same game in real time.

Time to check your understanding.

I have a question for you.

Which of the following is an advantage of using the client-server model for a network? Is it A, if a client machine breaks, it typically won't disrupt the entire network, B, it does not require any specialist technical support to maintain, or C, if the central server fails, only a single user is affected? Pause the video here whilst you think carefully about your answer.

Did you say A? Well done.

If a client machine breaks, it typically won't disrupt the entire network in a client-server model.

Okay, we are moving on to our first task of today's lesson, task A.

For part one, explain the two main roles in a client-server model network and describe what each role does.

For part two, describe two different types of servers found in a client-server model network and explain the purpose of each.

Pause the video here whilst you complete the task.

How did you get on? Did you manage to identify some roles in a client-server network? Well done.

Let's have a look at some sample answers together.

For part one, you were asked to explain two main roles in a client-server model network and describe what each role does.

In a client-server model network, the two main roles are the client and the server.

The client is a programme that typically runs on a device used by an end user, such as a laptop or mobile phone, and its role is to make requests for data or services.

The server is a programme on a computer that is responsible for fulfilling those requests by sharing resources or providing services to any authorised client.

For part two, you were asked to describe two different types of servers found in a client-server model network, and explain the purpose of each.

A file server is used to store and provide files to clients across the network.

Another type is a web server, which stores and provides web pages, so clients can view websites.

Alternatively, an email server stores and forwards emails, or a print server provides printing services and manages print queues across the network.

We've described more than two there.

Remember, if you had any different types of server, that's also absolutely fine.

Okay, so we've identified the roles in a client-server network.

Let's now move on to describe the purpose of a PAN, LAN, and a WAN.

You can describe a network by the type of area that they operate in.

A single user might have a laptop that is connected to a smartphone to share their internet access.

This is known as a personal area network or PAN.

A PAN is typically limited to a single user in the network with multiple connected devices.

For example, the user might also have a smartwatch that is connected to the smartphone to track heart rate, steps, and notify the user of new messages.

Time to check your understanding.

I have a true or false statement for you.

A laptop connected to a smartphone to share internet access is an example of a personal area network or PAN.

Is this statement true or false? Pause the video whilst you have a think.

That's right.

It's true.

Well done.

This is a common way that a PAN is formed, allowing devices to share internet connectivity.

A local area network or LAN has multiple users and is typically situated in a single building or room.

The devices on the network are local to each other.

A small office will typically use a LAN to allow for shared access to files and peripherals like printers.

You might also see a LAN in a household.

Members of the household might have laptops, smartphones, computers, and even TVs and other smart devices, all connected via the LAN.

When devices are connected across a wider geographical area, they form what we call a wide area network or WAN.

Often, lots of LANs are connected together to create a WAN, so here you can see an example where we have four local area networks which are connected together to form a wide area network.

Large businesses use WANs to share files and resources across multiple buildings in different locations.

They might have an office in Wales and an office in Scotland, both requiring access to shared files.

A WAN can make this possible.

Okay, time to check your understanding.

I have a question for you.

What is the main difference in terms of geographical area between a LAN and a WAN? Is it A, a LAN connects devices across a wider geographical area, while a WAN is limited to a single building, or B, a LAN is typically limited to a single building or room, while a WAN connects devices across wider geographical areas, or C, a LAN is only used in households, while a WAN is only used in large businesses? Pause the video here whilst you think carefully about your answer.

Did you select B? Well done.

A LAN is typically limited to a single building or room, while a WAN can connects devices across a wider geographical area.

Okay, we are moving on to our second task of today's lesson, task B.

For part one, I'd like you to explain the main purpose of a PAN, a LAN, and a WAN.

And then for part two, for each of these network types, a PAN, a LAN, and a WAN, describe a typical place or situation where you would find it being used.

Pause the video here whilst you complete the task.

How did you get on with the task? I'm sure you've done a fantastic job.

Well done.

Let's have a look at some sample answers together.

So for part one, you were asked to explain the main purpose of a PAN, a LAN, and a WAN.

The main purpose of a personal area network or PAN is to enable a single user's personal devices to communicate and share resources, like internet access or health data.

The main purpose of a local area network or LAN is to connect multiple users and devices within a limited area, allowing them to share files and peripherals.

The main purpose of a wide area network or WAN is to connect devices and share resources across larger geographical distances, often by linking many local networks together.

Did you have some similar responses? Remember, if you need to pause the video here and add detail to your answers, you can do that now.

For part two, you were asked for each of the network types to describe a typical place or situation where you would find it being used.

You would typically find a personal area network or PAN connecting a single user's devices over a very short distance, such as a smartphone to a smart watch.

A local area network or LAN is usually found in a single building or room, like a small office or a family household.

A wide area network or WAN connects devices across a wide geographical area, often linking multiple offices of a large business in different cities.

Okay, we've come to the end of today's lesson, "Types of network," and you've done a fantastic job, so well done.

Let's summarise what we've learned together in this lesson.

Within a client-server model network, devices take on specific roles as either clients or servers.

A client makes requests for information or services.

A server responds to these requests and provides the necessary services.

Different network types are used for communication over varying distances.

Personal area network or PANs are for short ranges.

Local area network or LANs are for limited areas.

And wide area networks or WANs are for large geographical distances.

I hope you've enjoyed today's lesson and I hope you'll join me again soon.

Bye.