What is a network? Definition, explanation, and examples

What is a computer network?

A computer network is a system that connects two or more computers for the purpose of exchanging and transmitting data. There are a variety of computing devices, from mobile phones to servers. They can also be wireless.

ARPANET, the first operational network, was built in the late 1960s with funding from the U.S. Department of Defense. At a time when computers were cumbersome and difficult to transport, government researchers used to communicate data. We’ve come a long way from that primitive network type. The internet is a network of networks that links billions of devices around the globe. Networks are used by businesses of all kinds to link the devices and shared resources of their employees, such as printers.

The traffic monitoring systems in big centers are an example of a large-scale computer network. These devices notify officials and emergency personnel of traffic flow and incidents. Using collaboration software such as Google Drive to share documents with remote coworkers is a simpler approach. Every time we make a video call, stream a movie, share files, send instant messaging, or simply browse the internet, a computer network is in operation.

Computer networking is the subfield of computer science concerned with the conception, construction, establishment, management, and security of computer networks. It combines computer science, computer engineering, and communications.

Major Components of a Computer Network

A computer network is composed of two basic components: nodes or network devices and links. The linkages bind two or more nodes together. Communication protocols determine how these links transport information. The communication endpoints, or origin and destination devices, are frequently referred to as ports.

1. Network Devices

Network devices, often known as nodes, are computational devices that must be joined in a network. Among the network devices are:

1. Computers, mobile phones, and other gadgets: These are end devices that users use often and directly. An email, for example, is sent from the mailing application on a laptop or mobile phone.
2. Servers: These are application or storage servers that perform the majority of the computation and data storage. The servers receive all requests for specific operations or data.
3. Routers: Routing is the process of deciding the network path that data packets will take. Routers are devices that redirect packets between networks so that they can eventually reach their destination. They improve the efficiency of huge networks.
4. Switches: Repeaters are to networks what transformers are to electrical grids—they are electronic devices that receive and clean or strengthen network signals. Hubs are repeaters that have numerous ports. They route the data to the next accessible port. Bridges are more intelligent hubs that only send data to the destination port. A switch is a bridge with several ports. To communicate with numerous network devices, multiple data connections can be inserted into switches.
5. Gateways:  Gateways are hardware devices that serve as “gateways” between two separate networks. They can take the form of firewalls, routers, or servers.

2. Links

Links are transmission media that come in two varieties:

• Wired: Coaxial cables, phone lines, twisted-pair cabling, and optical fibers are examples of wired technology used in networks. Optical fibers transport light pulses that represent data.
• Wireless: Wireless networks can be built using radio or other electromagnetic waves. This type of transmission is known as ‘wireless.’ Communication satellites, cellular networks, and radio and technology spread spectrums are some of the most prevalent instances of wireless links. Wireless LANs use spectrum technology to connect devices in a small area.

3. Communication Protocols

A communication protocol is a set of rules that all nodes involved in information transfer must obey. The internet protocol suite (TCP/IP), IEEE 802, Ethernet, wireless LAN, and cellular technologies are all examples of common protocols. TCP/IP is a conceptual model that standardizes network communication. These communication linkages are suggested to have four functional layers:

• Network access layer: This layer tells how the data is actually sent from one place to another. It looks at how the hardware sends bits of data through wires or fibers.
• Internet layer: This layer is in charge of putting the data into packets that people can understand and sending and receiving them.
• Transport layer: This layer makes it possible for devices to keep talking by making sure the connection is valid and stable.
• Application layer: This layer tells high-level applications how to connect to the network and start transferring data.

The majority of the present internet structure is based on the TCP/IP architecture, however the similar but seven-layered open systems interconnection (OSI) model continues to have a substantial influence. IEEE802 is an IEEE standard family that deals with local area networks (LAN) and metropolitan area networks (MAN) (MAN). Wireless LAN, often known as WLAN or Wi-Fis, is the most well-known member of the IEEE 802 family. 4. Network Security While nodes, connections, and protocols are the building blocks of a network, a contemporary network cannot survive without protections.

In addition, networks rely on defined protocols to execute discrete functions or convey various types of data regardless of the underlying technology.

Voice over IP (VoIP), for instance, can transmit IP telephone communications to any destination that supports the protocol. HTTP offers browsers with a standard method for displaying online pages. TCP/IP is a collection of protocols responsible for transmitting data and services over an IP-based network.

Various kinds of computer networks

Computer networks can be put into different groups based on things like how they send data, how big they are, how they are set up, and what their organizational goals are. The different types of networks, based on how far apart they are, are:

1. Nanoscale networks: These networks let tiny sensors and actuators talk to each other.
2. Personal area network (PAN): A PAN is a network that only one person uses to connect different devices, like laptops to scanners, etc.
3. Local area network (LAN): A local area network connects devices in a small area, like a school, hospital, or office building.
4. Storage area network (SAN):  is a dedicated network that helps store data in blocks. This is used in devices that store information, like disk arrays and tape libraries.
5. Campus area network (CAN): A campus area network is a group of LANs that are all linked together. They are used by universities, governments, and other large groups.
6. Metropolitan area network (MAN):  It is a large computer network that covers an entire city.
7. Wide area network (WAN): Wide area networks cover larger areas, like big cities, states, and even countries.
8. Enterprise private network (EPN): An enterprise private network is a single network that a large company uses to connect all of its offices.
9. Virtual private network VPN: is a private network that is built on top of a public network.
10. Cloud network: A cloud network is a wide area network (WAN) that gets its infrastructure from cloud services.

Depending on the goals of the organization, networks can be:

• Intranet: An intranet is a group of networks that are run and managed by the same group. It is usually the safest type of network because only authorized users can use it. In a local area network, an intranet is often found behind the router.
• Internet: The internet, also called the internetwork, is made up of many different networks that are linked together by routers and layered with networking software. This is a global system that links computer networks for governments, researchers, businesses, the public, and individual people.
• Extranet: An extranet is like an intranet, but it connects to other networks outside of the company. Usually, it is used to share resources with partners, customers, or employees who work from far away.
• The darknet: This is a network that runs on top of the internet and can only be reached with special software. It uses unique, customized communication protocols.

How are public networks and private networks different?

Public networks are a convenient way to connect to the Internet. They are often offered by nearby businesses and other public places.

• Before you can connect to some public Wi-Fi networks, you need to know the password. If you see a lock icon next to a Wi-Fi network in your list of available networks, it needs a password.
• Some networks let you connect without a password, but you have to log in with your web browser before you can use the Internet.
• On some public networks, you don’t even need a password. Any device that can connect to Wi-Fi can connect to these networks without having to log in.

Private networks have security measures in place to stop people from connecting to them without permission. Home, business, and school Wi-Fi networks, as well as mobile hotspots, often use private networks to keep things safe and to keep bandwidth.

Benefits of having a network

There are more pros to having a network than cons. In fact, many businesses wouldn’t be around if they couldn’t connect to some kind of network. Here are some good things about a network.

• Share data and information: One of the best things about a network is that all of the devices on it can share data and information. Networks also let you connect to databases and work together on more complicated tasks.
• Communication: A network lets everyone use chat, instant messaging, e-mail, and videoconferencing to talk to each other quickly.
• Share hardware: All users can share hardware that is connected to a network. Some examples of network hardware that can be shared are given below.

1. NAS (network-attached storage) can hold and give you access to a lot of data.
2. With a network printer, everyone on the network can print to the same printer.
3. Supercomputers and render farms are very powerful computers that can do tasks that would take a normal computer longer to do.

• Share software: You can also share software if you have the right license.
• Transferring money: If a person or business is connected to a secure network, they can send and receive money digitally between banks and users. For instance, a network could let a company not only handle the payroll of its employees but also transfer their pay to their bank accounts.

Disadvantages of a network

Even though a network has many benefits, which we’ve already talked about, it also has some drawbacks. Here are the bad things about a network.

• Viruses and malware: Networks make it easy for people to share information with each other. This is bad because it makes it easier for viruses and other bad software to spread from one computer to another on a network.
• Vulnerabilities: When a network is set up, it opens up new ways for computers to be accessed from far away, especially if they are connected to the Internet. With these possible new ways to get into a computer, it can make computers, users, and data on a network more vulnerable.
• Complexity: Networks are hard to set up and run, so someone with a lot of experience or a certification is needed to do it for a business or corporation.

What was the first network made up of computers?

ARPANET, which was built in the mid-1960s, was one of the first computer networks to use packet switching. It is the direct ancestor of the modern Internet. On October 29, 1969, the first ARPANET message was sent.