Computer Network

A computer network is a system that connects two or more computing devices for transmitting and sharing information. Computing devices include everything from a mobile phone to a server. These devices are connected using physical wires such as fiber optics, but they can also be wireless.

An example of a computer network at large is the traffic monitoring systems in urban cities. These systems alert officials and emergency responders with information about traffic flow and incidents. A simpler example is using collaboration software such as Google Drive to share documents with colleagues who work remotely. Every time we connect via a video call, stream movies, share files, chat with instant messages, or just access something on the internet, a computer network is at work.

Computer networking is the branch of computer science that deals with the ideation, architecture, creation, maintenance, and security of computer networks. It is a combination of computer science, computer engineering, and telecommunication.

How Does a Computer Network Work?

Basics building blocks of a Computer network are Nodes and Links. A Network Node can be illustrated as Equipment for Data Communication like a Modem, Router, etc., or Equipment of a Data Terminal like connecting two computers or more. Link in Computer Networks can be defined as wires or cables or free space of wireless networks.

The working of Computer Networks can be simply defined as rules or protocols which help in sending and receiving data via the links which allow Computer networks to communicate. Each device has an IP Address, that helps in identifying a device.

Basic Terminologies of Computer Networks

• Network: A network is a collection of computers and devices that are connected together to enable communication and data exchange.
• Nodes: Nodes are devices that are connected to a network. These can include computers, Servers, Printers, Routers, Switches, and other devices.
• Protocol: A protocol is a set of rules and standards that govern how data is transmitted over a network. Examples of protocols include TCP/IP, HTTP, and FTP.
• Topology: Network topology refers to the physical and logical arrangement of nodes on a network. The common network topologies include bus, star, ring, mesh, and tree.
• Service Provider Networks: These types of Networks give permission to take Network Capacity and Functionality on lease from the Provider. Service Provider Networks include Wireless Communications, Data Carriers, etc.
• IP Address: An IP address is a unique numerical identifier that is assigned to every device on a network. IP addresses are used to identify devices and enable communication between them.
• DNS: The Domain Name System (DNS) is a protocol that is used to translate human-readable domain names (such as www.google.com) into IP addresses that computers can understand.
• Firewall: A firewall is a security device that is used to monitor and control incoming and outgoing network traffic. Firewalls are used to protect networks from unauthorized access and other security threats.

Types of Computer Networks

• Nanoscale networks: These networks enable communication between minuscule sensors and actuators.
• Personal area network (PAN): PAN refers to a network used by just one person to connect multiple devices, such as laptops to scanners, etc.
• Local area network (LAN): The local area network connects devices within a limited geographical area, such as schools, hospitals, or office buildings.
• Storage area network (SAN): SAN is a dedicated network that facilitates block-level data storage. This is used in storage devices such as disk arrays and tape libraries.
• Campus area network (CAN): Campus area networks are a collection of interconnected LANs. They are used by larger entities such as universities and governments.
• Metropolitan area network (MAN): MAN is a large computer network that spans across a city.
• Wide area network (WAN): Wide area networks cover larger areas such as large cities, states, and even countries.
• Enterprise private network (EPN): An enterprise private network is a single network that a large organization uses to connect its multiple office locations.
• Virtual private network (VPN): VPN is an overlay private network stretched on top of a public network.
• Cloud network: Technically, a cloud network is a WAN whose infrastructure is delivered via cloud services.

Based on organizational intent, networks can be classified as:

• Intranet: Intranet is a set of networks that is maintained and controlled by a single entity. It is generally the most secure type of network, with access to authorized users alone. An intranet usually exists behind the router in a local area network.
• Internet: The internet (or the internetwork) is a collection of multiple networks connected by routers and layered by networking software. This is a global system that connects governments, researchers, corporates, the public, and individual computer networks.
• Extranet: An extranet is similar to the intranet but with connections to particular external networks. It is generally used to share resources with partners, customers, or remote employees.
• Darknet: The darknet is an overlay network that runs on the internet and can only be accessed by specialized software. It uses unique, customized communication protocols.