What is LAN?

A local area network (LAN) is a group of devices connected within a limited physical area such as a building, office or home. A LAN can range from a small home network with one user to a large enterprise network with thousands of users and devices. It connects devices that are within a single area, while Wide Area Networks (WANs) and Metropolitan Area Networks (MANs) cover larger geographic areas, connecting multiple LANs.

Components of a LAN typically include cables, access points, switches, routers and other devices that enable devices to connect to internal servers, web servers and other LANs via WANs. Virtual LANs have also emerged due to the rise of virtualization, enabling network administrators to group network nodes logically and partition their networks without major infrastructure changes. For example, a business or organization may have multiple departments with computers connected to the same switch but segmented to behave as if they are separate.

The benefits of a LAN include sharing a single Internet connection, sharing files and printers and accessing and controlling devices connected to the LAN. LANs were initially developed in the 1960s for colleges, universities and research facilities, primarily to connect computers to other computers.

LANs did not become commonplace until Ethernet technology was introduced in 1973 and subsequently commercialised in 1980, soon becoming standard practice.

The deployment of Wi-Fi technology has expanded the types of devices connected to a LAN, making it commonplace in various environments, including restaurants, coffee shops, stores, and homes. Today, nearly everything can be connected to a LAN, including PCs, printers, phones, smart TVs, stereos, speakers, lighting, thermostats, window shades, door locks, security cameras, and even household appliances like refrigerators and coffee makers.

Broadly speaking, there are two types of Local Area Networks (LANs): client/server and peer-to-peer.

A client/server LAN involves a central server connected to multiple devices (clients) it manages. The server controls file storage, device, application access and network traffic. Clients can be any device connected to the network and connect to the server either through cables or wirelessly.

It is common for a variety of applications to be stored on the LAN server. Users can access databases, email, document sharing, printing, and other services through the applications running on the LAN server. The network or IT administrator manages the read and write access to these services. Typically, medium to large businesses, governments, research institutions, and education networks use client/server-based LANs.

A peer-to-peer LAN, on the other hand, does not have a central server and is not as suitable for heavy workloads compared to client/server LANs. Therefore, peer-to-peer LANs are generally smaller. In this type of LAN, each device contributes equally to the network’s operation by sharing resources and data through wired or wireless connections to a switch or router. Most home networks operate on a peer-to-peer basis.