Table of Contents
What is Computer Network?
A Computer Network is a network set up by connecting two or more computers and other supporting hardware devices through communication channels. A network enables computers to communicate with each other by sharing commands, data, etc, including hardware and software resources.
Each computing device in a network is called a node or station. The nodes can be routers, personal computers, and servers. Protocols are the rules using which the Data transformation is done via the network. Each part of the network has to follow a set of rules called protocols to pass information over wired or wireless connections.
Working of Computer Network
Nodes and Links are the basic building block of a Computer Network. Data is transmitted and generated through the nodes such as computers, switches, and modems. After that, a transmission media which is the link is used to bond among the nodes. The nodes will transfer and receive data via connections by following the protocols. The Computer Network Architecture defines the design associated with these physical and logical components. It provides the definitions for the network’s physical components, functional organization, protocols, and procedures.
In other words, the working of Computer Networks can simply be defined as rules or protocols which help in sending and receiving data via the links which allow Computer networks to communicate. Each device is identified with the help of an IP Address assigned to it.
Types of Computer Networks
A computer network is a group of computers linked to each other that enables the computer to communicate with another computer and share its resources, data, and applications. It allows us to share resources such as printers, scanners, etc. Through computer networks, expensive software and database can also be shared amongst network users. It facilitates communication between two computers and allows the exchange of data between them.
We can categorize a computer network based on its size. A computer network is mainly of four types which are as follows:
- LAN(Local Area Network)
- PAN(Personal Area Network)
- MAN(Metropolitan Area Network)
- WAN(Wide Area Network)
Local Area Network (LAN)
A computer network that operates in a small area, connecting computers in a small geographical area like within an office, company, school, or any other organization is known as Local Area Network or LAN. This type of network can be wired, wireless, or a combination of both. In LAN, the devices are connected with each other using an Ethernet cable, which offers an interface to connect multiple devices like routers, switches, and computers. Example- We can easily create a LAN at our home, office, etc by using a single router, a few Ethernet cables, and computers. One computer may act as a server and other computers, which are part of the network, may serve as clients in this network.
Characteristics of LAN
- LAN network size is small consisting of only a few kilometres.
- In network topologies such as bus, ring, mesh and star, LAN is used.
- The data transmission rate is high, ranging from 100 Mbps to 1000 Mbps.
- Some network devices connected to the LAN will be limited.
- If more devices are added than prescribed network may fail.
- LAN Offers higher speed than WAN and MAN.
Metropolitan Area Network (MAN)
Metropolitan Area Network or MAN is a high-speed network spreading over a large geographical area such as a metro city or town. MAN is set up by connecting the local telephone exchange lines and local area networks using routers. It can be operated by a private company, or it may be a service provided by a company such as a local telephone company. This network provides fast communication via high-speed carriers or transmission media such as copper, fiber optics, and microwaves. It is ideally used by people in large areas who want to exchange data.
The commonly used protocols for MAN are X.25, Frame Relay, Asynchronous Transfer Mode (ATM), xDSL (Digital Subscriber Line), ISDN (Integrated Services Digital Network), ADSL (Asymmetrical Digital Subscriber Line), and more.
Characteristics of MAN
- MAN ranges in size from 5km to 50km.
- MAN can be set up and connected to a WAN at less cost.
- This network is maintained and managed by either the user group or the Network provider.
- It can send local emails fast as the speed of data transfer is more than WAN.
- MAN can be easily set up by connecting to various LANs
- It allows to share the internet connection, and thus multiple users can have access to high-speed internet.
Wide Area Network (WAN)
Wide Area Network or WAN is extended over a large geographical area and is not confined within an office, school, city, or town. This network is mainly set up by telephone lines, fibre optic, or satellite links. Big organizations like banks, and multinational companies use WAN to communicate with their branches and customers across the world. It is structurally similar to MAN but varies from it in terms of range. MAN covers up to 50 Km, whereas WAM can cover distances larger than 50 Km, 1000km or more.
TCP/IP Protocol in combination with networking devices such as switches, routers, firewalls, and modems are used for the working of WAN. This network is designed to link small networks like LANs and MANs to create a large network and does not connect individual computers. The internet is considered the largest WAN in the world as it connects various LANs and MANs through ISPs.
Public networks such as telephone systems, leased lines, or satellites are used to connect the computers to the wide area network. WAN is a large setup connecting the remote computer systems hence the users of a WAN do not own the network. However, the users are required to subscribe to a service provided by a telecommunication provider to use this network.
Characteristics of WAN
- WAN spreads over a large geographical area of 2000 km or more i.e., from one country to another country and has a much larger capacity.
- Regional resources can be shared using a WAN.
- WAN provides an ideal platform for companies that need a live server for their employees to exchange updated files within seconds.
- This network offers high bandwidth than a normal broadband connection. It offers uninterrupted data transfer and communication resulting in the increase of productivity of your company.
- It helps you to hire employees in different countries and assign them to work from your office, distributing your workload to other locations.
Personal Area Network (PAN)
Personal Area Network or PAN is a network arranged within a person, usually within a range of 10 meters. This network is used for connecting computer devices for personal use. The idea of PAN was first introduced by a research scientist named Thomas Zimmerman. This network covers an area of 30 feet. PAN is developed using personal computer devices such as laptops, mobile phones, media players and play stations.
A Personal Area Network can be classified into two categories-
- Wireless Personal Area Network: Wireless Personal Area Network is developed by simply using wireless technologies such as WiFi, and Bluetooth. It is a low-range network.
- Wired Personal Area Network: Wired Personal Area Network is created by using the USB.
Characteristics of PAN
- Personal Area Network is the smallest network of computers.
- Bluetooth or other infrared-enabled devices could be used to connect devices.
- PAN has a connectivity range of 10 meters.
- This computer network can cover up to 30 feet in diameter.
- With the help of this network, personal devices of a person can be connected to each other.