A computer network is made up of two or more computers that are linked together by cables (wired) or WiFi (wireless) to transmit, exchange, or share data and resources. Hardware (such as routers, switches, access points, and cables) and software are used to create a computer network (e.g., operating systems or business applications).
A computer network’s location is frequently defined by its geographical location. A LAN (local area network), for example, connects computers within a certain physical place, such as an office building, whereas a WAN (wide area network) connects computers across continents. The internet, which connects billions of computers around the world, is the most well-known example of a WAN.
A computer network’s purpose, the protocols it uses to communicate, the physical arrangement of its components, and how it manages traffic can all be used to further characterise it. Computer networks allow for communication in all areas of business, entertainment, and research. Computer networks are responsible for the internet, online search, email, audio and video sharing, online shopping, live-streaming, and social networks.
As networking requirements changed, so did the sorts of computer networks that served those requirements. The following are the most frequent and widely used types of computer networks:
- LAN (local area network): A LAN is a network that connects computers over a small distance to exchange data, files, and resources. A LAN, for example, can connect all of the computers in a building, a school, or a hospital. LANs are typically privately owned and operated.
- WLAN (wireless local area network): A WLAN is similar to a LAN, but it uses wireless connections to connect devices on the network.
- WAN (wide area network): A WAN connects computers over a large distance, such as from one region to another or even continent to continent.
The internet is the world’s greatest wide-area network, linking billions of computers all over the world. For WAN administration, you’ll usually encounter collective or dispersed ownership structures.
- MAN (metropolitan area network): A MAN is a network that is larger than a LAN but smaller than a WAN. MANs are often owned and managed by cities and government agencies.
- PAN (Personal Area Network): A PAN is a network that only serves one individual. If you have an iPhone and a Mac, for example, you’ve very certainly set up a PAN to share and sync content—text messages, emails, images, and more—across both devices.
- SAN (storage area network): A SAN is a specialised network that allows access to block-level storage—a shared network or cloud storage that appears and functions to the user as if it were a physical storage drive connected to a computer.
- CAN (campus area network) is sometimes known as a corporate area network. A CAN is bigger than a LAN, but it’s not as big as a WAN. Colleges, universities, and business campuses are all served by CANs.
- VPN (a virtual private network): A VPN is a secure, point-to-point connection between two network endpoints (see below for further information on nodes). A VPN creates an encrypted route that prevents hackers from accessing a user’s identity and access credentials, as well as any data sent.
Terminologies and concepts used
- IP Address: An IP address is a unique number provided to each device connected to a network that communicates using the Internet Protocol. Each IP address indicates the device’s host network as well as its location on that network.
When one device sends data to another, the data includes a ‘header’ with the transmitting device’s IP address and the destination device’s IP address.
- Nodes: In a network, a node is a connection point that can receive, send, create, or store data. To gain access to each node, you must supply some form of identity, such as an IP address. Computers, printers, modems, bridges, and switches are examples of nodes. Any network device that can identify, process, and transmit data to other network nodes is referred to as a node.
- Routers: A router is a physical or virtual device that delivers data packets containing information between networks. Routers examine the data contained in packets to identify the most efficient path for the data to reach its final destination. Data packets are routed through routers until they reach their destination node.
- Switches: A switch is a network device that connects other devices and manages node-to-node communication, ensuring data packets reach their final destination. A switch delivers data between nodes in a single network, whereas a router sends data between networks. The term “switching” is used to describe how data is transmitted between devices in a computer network. The following are the three primary forms of switching:
- Circuit switching is a network technology that creates a dedicated communication connection between nodes. This dedicated path ensures that the entire bandwidth is available during transmission, ensuring that no other traffic can pass through.
- Packet switching is splitting data into small, independent components called packets, which put less strain on the network due to their small size. The packets traverse the network on their way to their final destination.
- Message switching transfers a message in its entirety from the source node to the destination node, moving from switch to switch.
- Port: A port is a network device that identifies a specific connection. A number is assigned to each port. If an IP address is like a hotel address, ports are the suites or room numbers within that hotel. To determine which application, service, or process should receive specific messages, computers employ port numbers.
- Network Cable Types: Ethernet twisted pair, coaxial, and fibre optic cables are the most prevalent network cable types. The size of the network, the configuration of network elements, and the physical distance between devices all influence the cable type chosen.