Network devices:

What is the Network ?

When two or more computers connected in a order to communicate or share resources this is called a network. This connection made with wires or wirelessly.

what is the internet ?

internet is a system of interconnected networks to communicate with different networks and devices with some particular rules. These rules are called Protocols. There are many protocols for different tasks. TCP/IP is the core one. Transmission Control Protocol / Internet protocol handling addressing, routing, and reliable delivery. There exits more protocols like HTTP, FTP, DNS, SMTP etc.

A IP Address (Internet Protocol Address) is unique id of each device connected to the network, which network use Internet Protocols for communication. By IP Address network locate a device and enable communication for that device.

So, by using internet we connect or communicate with another.

The backbone of internet

At the backbone, internet relies on vast physical infrastructure. High quality optical fiber-optic cables, routers, switches, Firewall, Load Balancer and Modem connect the networks worldwide. This backbone of internet is managed by major telecommunications companies, internet service providers (ISPs), and content delivery networks (CDNs). Massive amounts of data flow through undersea cables every second, connecting the world on a large scale.

The network devices

Routers:

Router determine the route of data packets towards its destination IP address efficiently. When traffic increased, it determine the best path for data packets towards its destination its called dynamic routing. Router also make sure that multiple device connect to same Internet connection.

There are several types of Routers, but most common are LAN, WAN.

WAN (Wide Area Networks) operates in large scale of networks. A WAN, by contrast, is a large network spread out over a vast geographic area.

LAN(Local Area Network) operates in small area.

We compare a Router with traffic controller and data packets with aeroplanes. Each aeroplane have its specific destination, and we don’t want a aeroplane disturbs another of its route, so we use traffic controller its tell which route is best based on current traffic. So that’s why we use Router.

Modem:

Modem used for connect a network to Internet. Modem stands for Modulator/Demodulator. The main function of modem is convert analog signals (which is come from ISPs) to digital signals (0 & 1) which is understand by our device this is called modulating. Its also convert digital signal to analog signal in the time of transmission this called demodulating. Modems can modulate as well as demodulate the signals at same time.

we compare Modem with a translator.

There are some problem with modem:

If we connect a modem with a hub (for multiple device connection) its slows down.

The modem cannot track the traffic between the LAN and the internet.

When using a modem a limited number of network devices can be connected to the internet.

so bypass this problems we use Router along side Modem,

Switch:

A Switch is used for connection between device in a network. Unlike a router, a switch only sends data to the single device it is intended for (which may be another switch, a router, or a user's computer).

Switch VS Router:

Routers select paths for data packets to cross networks and reach their destinations. Routers do this by connecting with different networks and forwarding data from network to network — including LAN,WAN etc.

its means Router is important for network connection, in another hand switches are only used for interconnecting devices.

Homes and small offices need routers for Internet access, but most do not need a network switch. However, large offices, networks, and data centres with dozens or hundreds of computers usually do require switches.

Hub:

A network hub is a basic device that connects multiple computers in a Local Area Network (LAN).

Hub vs Switch

Hub broadcasting the data, which device connected to hub get access the data. It is slower than Switch. Hub is used rarely now days, it is replaced by Switch.

In other hand, Switch sends specific data to specific device. Switch really fast.

Firewall:

Firewall is security device or software. We compare Firewall as gateman of a building, it allow trusted people enter the building and reject unwanted people. Firewall do the same, it’s monitor, allow or block incoming outgoing data traffic by predefined security rules.

There are different types of firewalls:

Software Firewall: install our computer or device.

Hardware Firewall: used in routers

Modern firewalls are smart block traffic, they analyse data packets, detect threats, and help keep networks safe without affecting performance.