A network is defined as a group of two or more computer systems linked together. There are many types of computer networks, including the following:
- Local-area networks (LANs): The computers are geographically close together (that is, in the same building).
- Wide-area networks (WANs): The computers are farther apart and are connected by telephone lines or radio waves.
- Campus-area networks (CANs): The computers are within a limited geographic area, such as a campus or military base.
- Metropolitan-area networks MANs): A data network designed for a town or city.
- Home-area networks (HANs): A network contained within a user’s home that connects a person’s digital devices.
In addition to these types, the following characteristics are also used to categorize different types of networks:
- Topology : The geometric arrangement of a computer system. Common topologies include a bus, star, and ring. See the Network topology diagrams in the Quick Reference section of Webopedia.
- Protocol : The protocol defines a common set of rules and signals that computers on the network use to communicate. One of the most popular protocols for LANs is called Ethernet. Another popular LAN protocol for PCs is the IBM token-ring network .
- Architecture : Networks can be broadly classified as using either a peer-to-peer or client/server architecture.
Computers on a network are sometimes called nodes. Computers and devices that allocate resources for a network are called servers.
Image: Network Topology diagram
(v.) To connect two or more computers together with the ability to communicate with each other.
Network topology describes how a network is arranged physically and logically. This description includes how links and nodes are connected in relation to each other. There are many varieties of network topologies including:
- Bus: Each computer and network device is connected to a single cable or backbone.
- Star: Every host device is connected to one central host.
- Ring: Each network device connects to exactly two other network devices, which forms a single continuous pathway for signals to move through each device, like a ring.
- Mesh: Each network device is connected in a way where each device distributes data amongst each other.
- Tree: Each computer device is connected like branches on a tree; it is a combination of bus and star network topology.
Public vs. private networks
There are two types of networks one can connect to. This includes private and public networks. A public network is a type of network in which anyone who has access to and through it can connect to the internet. A private network involves restrictions that are established to promote a secured environment. Some things to note when it comes to public and private networks include:
- Private networks require a password, most public networks do not
- Some public networks (like hotels or businesses) require a web login for authentication
- Public networks (like at airports and cafes) should be used with caution and a VPN
Examples of network devices
- Internet-enabled devices such as laptops, smartphones, gaming consoles, printers, smart home devices
- Servers are pieces of computer hardware or software that provides functionality for other programs or devices
- Firewalls monitor and filter incoming and outgoing network traffic based on a business’s previously established security policies
- Bridges connect two LANs and controls data flow between them
- Switches learn which machine is connected to its port by using its IP address
- Repeaters amplify received input signals to a higher frequency domain, so it is reusable and scalable
- Hubs are physical layer networking devices used to connect multiple devices in a network
- Modems are small boxes that connect your devices to the internet using cables
- Routers are devices that forward data packets between computer networks
- NICs, or network interface cards, provide computers with a dedicated, full-time connection to a network