NETWORK DEVICES

In the last posts, we saw what a network is and different types of networks like LAN, MAN, WAN, and the internet. Today, let’s look at the main devices that actually live inside these networks. We will keep it very simple and talk about the devices you already see at home or in a small office like phones, laptops, switches, routers, and Wi-Fi boxes.

Network Devices

NETWORK DEVICES
These devices are the physical hardware components that enable computers to connect, communicate and share resources over a network and these transfer data in a fast, secure and correct way over same or different network.
Now let us start by learning about the each network device in detail with a real world example.
1) REPEATER:
Sometimes, network signals get weak when they travel over long cables or through walls. A repeater is a simple device that helps in this case. It listens to the weak signal, rebuilds it, and sends it again at full strength. It doesn’t try to understand the data, it just boosts the signals so that your network can reach farther without loosing quality.

To explain you using the real life example, imagine there are 2 people standing far apart and shouting at each other and the voice is getting weaker as the distance increases. So, to resolve it if we place a person in the middle who can hear the message clearly and repeats to the other person and this helps both sides to communicate clearly.

In the same, the person in the middle is like a repeater: they donot change the message but helps the message to reach it farther.
In networks, repeaters does the same thing, they receive a signal, regenerates it and sends it again so that it can travel farther without losing quality.

2) HUB:
A Hub is simplest network device which connects several devices in a small network and forwards the data it receives to all the connected devices without checking who the real receiver is.
It works at the physical layer(Layer 1) and does not understand MAC addresses or IP addresses.
For example, You are in a class and you want to share a secret with your friend, now instead of whispering it you shout it out loud and everyone heard it.
So, now everyone knew the secret, in the same way hub forwards the message to each and every connected devices with out sending it to the particular device.

HUB

3) Bridge:
A Bridge is a network that connects two LAN segments and lets them work like a bigger LAN, while also helping to reduce the traffic between them.
It works at the layer 2(data link layer) and is smarter than the hub, because instead of sending the data to all the connected devices, it just send it to the particular device.

For example, Imagine there are two apartment blocks with their own small internal roads. A little bridge connects them. People move freely inside each block and only cross the bridge when they really need to visit the other side like in the same way a network bridge connects two parts of a LAN and only forwards data between them when the destination device is on the other side.

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Bridge

4) Switch:
A Switch is the device that connects many devices inside the same LAN, and forwards data only to the right device it is meant for, using MAC addresses to decide where to forward it.

It works at Layer 2(data link layer) and learns which device is on which port by looking at their MAC addresses.

Bridge VS Switch:
Both bridges and switches work at Layer 2 and use MAC addresses to decide where to send data; in modern networks, a switch is basically a faster, multi-port version of a bridge.

5) Router:
A router is a device that connects one network to the other networks and sends data along the right path so it reaches it’s destination.

It works at Layer 3(network layer) and uses IP addresses to make decisions, unlike switches/bridges which use MAC addresses.

For example, you write a letter to a friend in another city. You go and drop the letter at you local post office and post office checks the address, decides which city it should go next and sends the letter to the correct city’s main post office, not to every address.
Here the local post office acts as the router, it checks the address(IP address) and decides the next best place to send the data, instead of sending it everywhere.

Router

Differences between the Network Devices

Differences between the network devices

So now you’ve met the main network devices: end devices that use the network, switches and bridges that connect devices inside a LAN, hubs and repeaters from older/simple networks, modems that bring the internet into your home, and routers that connect your LAN to other networks. That’s it for today — thanks for reading, and in the next post we’ll look at how data actually moves between these devices step by step, using more real-life examples.