Set Up TCP/IP Networks

Identify Transmitters and Receivers

Before you create a network in Packet Tracer, you need to identify the necessary components.

Let’s start by taking a look at the equipment that initiates communication: end devices. These are the devices capable of sending and receiving messages.

I’m deliberately using the word device, as it’s a very generic term that covers:

• The computers, tablets, and smartphones you use every day.

• The servers you store, host, and search for information.

• Landline phones, which now use networks in the same way as computers.

• Printers, photocopiers, and other scanning equipment.

As you can see, this term applies to a whole range of objects! But what do all of these devices have in common?

What they have in common is their ability to translate a human message (voice, image, video, text, etc.) into a digital message, or binary language.

Once the message is converted into digital (or digitized), it will be transferred to another device. To deliver this message, you need a transmission medium.

Choose the Right Transmission Medium

When you want to travel somewhere by car, you use a transmission medium: the road. Without that, you wouldn’t get very far! You might take the backroads or the highway. Or you might even choose a different medium and go by rail or air. As you can see, there are many possible types of transmission media.

Identify the Different Types of Transmission Media

In the world of networks, there are three types of transmission media:

• Copper cables, the most widely-used of which are twisted pair cables.

• Fiber optic cable. 

• Wireless communication. 

Take Into Account Different Parameters to Choose Your Transmission Medium

There are several parameters that will influence your choice of medium:

• The type of equipment to be connected: PC, server, telephone, tablet, etc.

• The distance between two pieces of equipment.

• The external environment: temperature, disturbances, humidity, etc.

• The network's use case: user mobility, speed, etc.

The table below will help make things clearer.

The most commonly used medium is twisted pair copper cable. It’s compatible with most equipment and provides high speed and excellent security. This type of cable is robust and affordable. It’s ideal for connecting employees working on desktop computers.

However, if your equipment is more than 100m apart or your network is subject to a lot of electromagnetic radiation, it won’t be ideal. In this case, you should choose fiber optic cable. You will often see business equipment connected using fiber optic cable, but it’s rarely used for home networks because of the limitations linked to its fragility. However, it’s the preferred transmission medium for MAN and WAN networks.

Finally, if you want to provide your users with a certain degree of mobility, you can use a wireless connection. Almost all sites now use wireless for at least a part of their network to connect smartphones, tablets, and laptops. There’s just one thing to keep in mind—wireless connections can be less secure than wired connections if not configured correctly.

Connect Your Devices to the Transmission Medium

Now you’ve chosen your transmission medium, you can use it to connect your devices.

Identify Your Devices’ Network Cards

To do this, check that your devices are equipped with a network card or interface. This is an electronic card with a port to connect your medium.

Normally, a network card will already be installed on the device, as this component is just as essential as a graphics or sound card. But, if not, you’ll have to get one for your device.

Don’t worry! It’s easy to display your computer’s network card(s). If you’re using Windows 10:

1. Open the Run window using the keyboard shortcut Windows + R.

2. Enter “ncpa.cpl” and click OK. 

A window will appear with all Network Connections, detailing all of your device’s network cards and interfaces.

The Role of Network Cards

The role of a network card is to transform binary data into electricity, light, or electromagnetic waves, so it can travel via the transmission medium.

The Different Types of Network Card

Each type of network card has a transmission medium, and all of this is governed by standards.

Network standards are massive catalogs containing technical blueprints for manufacturing network equipment. They’re challenging to understand but essential to make sure equipment and communication are the same globally. These standards also act as specifications, as manufacturers must follow them to obtain marketing authorization.

Here’s a summary of the equipment used in LANs:

Wireless connections are mainly used to provide mobility and have the benefit of avoiding using additional cables. The most commonly used standard for communications within a WLAN (wireless local area network) is Wi-Fi or IEEE 802.11. From the end user’s point of view, Wi-Fi brings nothing but benefits. But from a more detailed technical perspective, things are more complex.

Security is a major consideration when working with wireless connections. Because devices aren’t physically connected, they are more likely to be intercepted. However, there are encryption mechanisms to avoid this. These mechanisms use a WPA-type encryption key (this stands for Wi-Fi Protected Access) upon connection. 

If your network is protected by an encryption key, the messages sent are indecipherable by third parties. This is an essential feature to enable if you want to use Wi-Fi.

Create a Simple Network Between Two Devices

Now let’s get back to your task - to make a start on the job for Tinos driving school. The client, Mr. Falman, wants to transfer data between his desktop computer and a file server. For the moment, he only has these two devices on the premises.

Choose your Transmission Medium

You only need to choose one transmission medium, as there’s only one connection to be made between Mr. Falman’s computer and his server.

You know that:

• The server and the computer are immobile devices, located in the same room, a few meters apart.

• The main constraint is data security.

In this case, copper network cable is clearly the best option. Therefore, the two devices need to be equipped with a suitable network card. Luckily, the client has told you that the right type of network card is already in place.

Simulate the Architecture With Packet Tracer

Before setting up this architecture, you decide to simulate it in Packet Tracer. Watch how to do this in the video below.

When you want to use twisted pair copper cables, remember that there are two types: straight-through and crossover cables. The difference between them is how the eight wires contained in each cable are arranged.

• A crossover cable connects two end nodes directly (i.e., PC to PC, PC to printer, or PC to server).

• Straight-through cable is used for networks containing intermediary nodes, which we’ll look at in the next chapter.

In straight-through cables, the eight wires are in the same order at both ends of the cable, but in crossover cables, they are in a different order:

Over to You!

Now you’ve seen how to connect two devices. It’s time to develop a simulation model in Packet Tracer! It’s over to you now. Try to develop the architecture the client requires in Packet Tracer, choosing the right equipment and cables.

Answers

You can find the answer sheet here to check your work.

Simulate Connection of an Extra PC in Packet Tracer

A few days later, the client calls you back. He’s just hired his first employee, who also needs access to the file server from his laptop. Unfortunately, when you try to connect the new PC to the server in Packet Tracer, a message informs you that there are no ports available!

This is because the server only has one RJ45 port, as there is only one network card.

There are two possible solutions:

• Add an extra network card to your server.

But imagine if a third employee is recruited, they would also need access to the server. You’d have to add a third network card, and the server would end up with as many network cards as there were employees—this would be impossible on a large scale!

• Add an intermediary device to your network—this is the best option.

Let’s Recap!

• You can use twisted pair copper cables (or Ethernet cables), fiber optic cables or a wireless network to connect two devices.

• You should choose your transmission media based on the physical environment where the devices are located.

• The network card of each device is linked to the transmission medium via a port, or an antenna for wireless connections. It converts the message before sending it via the medium. 

• The conformity of network equipment is guaranteed by the standards:

  • IEEE 802.3 or Ethernet for wired networks.

  • IEEE 802.11 for wireless networks (WLANs).

Well done, you’ve connected two of Tinos’ devices! Let’s go to the next chapter to add an intermediary device to your network.

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