What is a computer network? Types topologies and devices

Today we will learn about what a computer network is and what it is called, how many types of topologies there are and the equipment used to build a computer network.

What is a computer network?

When two or more computers are connected using one way or another, it is called a computer network.  

 

As a result, data can be transferred from one computer to another. This network is usually a collection of many computers. Since we are using the internet, it is basically working through a computer network. 

 

However, many devices are needed to create this computer network. What is needed to build a computer network is called network tools or equipment or devices. In addition to this, there are some terms or keywords in a computer network. 

 

Computer networks are made up of servers, clients, media, network adapters, resources, users, protocols, etc.

 

How many types of computer networks and what

Computer networks can generally be divided into 4 parts. E.g.

•          PAN (Personal Area Network)

•          LAN (Local Area Network)

•          MAN (Metropolitan Area Network)

•          WAN (Wide Area Network)

 

The network can usually be divided into 4 parts.

Personal Area Network (PAN):

The network that is created at the personal level is called Personal Area Network or PAN. Personal area networks are usually used to communicate between two computers. PAN is made by cable or wire or Bluetooth.

Local Area Network (LAN):

Local Area Network is abbreviated as LAN. The network that is formed between several computers in the same building is called Local Area Network. The cost of the devices used in it is very low. 

 

Devices used in LAN networks are hubs, switches, repeaters. At present local area network or LAN is used in schools, colleges, universities, banks, small and medium offices, courts and businesses. Its main purpose is to share data and resources between devices.

Metropolitan Area Network (MAN)

The Metropolitan Area Network, abbreviated as MAN. The network consisting of several LANs located within the same city is called the Metropolitan Area Network (MAN). 

 

This network can extend up to 50-65 miles. Its data transfer speed can be gigabit per second. Devices used in such networks are switches, microwave antennas, routers, etc. 

 

Wide Area Network (WAN)

Wide Area Network, also called WAN for short. The network that develops over remote lanes is called the wide-area network. 

 

 

Such networks are usually created within the country or around the world.

 

What is network topology? How many types and what are they?

The network topology is the layout or connection layout between different computers in a computer network. How many types and what are the network topologies

 

There are six types of network topology-

•          Bus Topology

•          Star Topology

•          Ring Topology

•          Tree Topology

•          Mesh Topology

•          Hybrid Topology

 

Bus network topology:

In such a network all workstations are connected with transmission media. This transmission is connected to the media via a short cable.

 

An important feature of bus topology is that information flows in both directions through the cable. When it wants to transfer data from one computer to another, it first sends the address to the destination computer in this transmission media.

Star Network Topology:

Many home networks use star topology. A star network has a "central hub" known as a "hub node" that can be a network hub, switch, or router.

 

Compared to the bus topology, a star network usually requires more cables, but a failure of any star network cable will only remove a computer's network access, not the entire LAN. (But if the hub fails, the whole network fails too)

 

Ring network topology:

This method looks like a round circle and is called Ring Topology. Here each computer is connected to two other computers. In this case, if a computer is damaged, the entire network becomes inoperable. 

 

Tree network topology:

A tree topology joins a bus in multiple star topologies together. In its simplest form, only the hub devices are directly connected to the tree bus and each hub device acts as the root of the tree. 

 

The future expansion of the network can be further enhanced by a bus/star hybrid approach (this is limited by the number of devices due to the transmitted traffic) or a single star (limited by the number of hub connection points) alone.

 

Mesh topology:

The topology in which each computer in the network is connected to each computer is called mesh topology or interconnected topology. This topology simply takes more than all other topologies.

Hybrid network topology:

Hybrid networks are networks that are made up of different topologies such as star, ring bus, etc. The Internet is a hybrid network because of the combination of almost all types of topologies.

 

How is the network formed?

To create a computer network or networking, it is basically necessary to connect the nodes to a link. Today, Office UJ and Home UJ have become a popular means of connecting devices to the network through wireless technology. 

 

But it is still used in many offices or large networks. Because wire or fiber optic cable is much faster and more secure than wireless technology. 

 

Is it necessary to connect your computer to another computer network first?

Each node in the network must have a special circuit, called a network card or network interface card or NIC. Network cards are built-in on today's new computers or laptops. 

 

But if your computer is old, you need to insert a separate network card so that it can be connected to other computers on the network. Each network card has a unique code number that identifies the card and is called a MAC or Media Access Control address. 

 

You can compare a MAC address with a phone number. Just as we type a message to send an SMS to a number, so a computer on a network sends a message to another computer if it wants to send a message to its MAC address.

 

Moreover, it is possible to ensure that any device on the network has permission to access any file through Mac. Suppose I have a Mac White List of a specific device on the router, then only that device can be connected to my network. Macs will be checked when other devices want to connect, and connections will not be provided if they do not match. 

 

This will prevent hackers or networks from connecting to unfamiliar devices.

 

Moreover, the bigger the networking, the bigger the line you will need. If you want to create a network via wireless and if the network is large, you need to use a repeater or signal booster to boost the signal. You will also need switches, hubs, routers, etc.

 

Protocol:

Computers always follow the logic, and where there is logic there are specific rules. Computer networks can be compared to an army. Just as all the members of the army follow the rules of that team,

 

so all the computers in the network follow the rules of that network. Speaking of LANs, for example, every node connected to a LAN (computer or other devices such as a printer, scanner) must be connected in a simple pattern called network topology. 

 

If you want you can connect the computers by drawing long lines, here the line from one computer to another computer, from one to another will work. 

 

Again, the machines can be connected in Star SEP or the machines can be connected by making a connection loop by drawing a ring. This is called a protocol. 

 

By connecting to the same line, the devices both exchange and transmit data at the same time, so if the protocol is not followed, there will be confusion and it will not be possible to establish a relationship with each other.