2.1.1 Network Purpose, LANs and WANs
Computer networks connect devices so that data, hardware and services can be used more effectively. Networks can also be classified by their geographical reach, ownership and the way their communication links are provided.
This section focuses on why devices are networked and how a local area network differs from a wide area network.
By the end of this section, you should be able to:
- explain several purposes and benefits of connecting devices in a network;
- compare LANs and WANs using geographical scope, control and infrastructure;
- apply the LAN–WAN distinction to an unfamiliar situation.
Why connect devices?
A computer network is a group of connected digital devices that can exchange data. The devices may include workstations, laptops, phones, printers, servers, sensors and other computer-controlled systems.
The benefit of a network is not simply that devices are connected. The connection must produce a useful result for users or for the organisation.
| Purpose | Original example | Resulting benefit |
|---|---|---|
| Share data | A product team opens project files from managed network storage. | Staff can work from a consistent set of current documents. |
| Share hardware | Several engineering workstations use one specialist large-format printer. | The organisation avoids buying and maintaining a separate printer for every user. |
| Provide services | Students access the same learning platform from classrooms and the library. | Applications and information are available from different devices and locations. |
| Support communication | Staff use messaging, shared calendars and collaborative documents. | Information can be exchanged quickly and teamwork becomes easier to coordinate. |
| Centralise management | Administrators manage accounts, permissions, updates and backups. | Security and maintenance policies can be applied more consistently. |
| Reach remote resources | A regional office accesses a database stored at the organisation's main site. | Users can work with resources that are not stored on their own device. |
Common mistake
Naming a shared resource is not yet a complete explanation of a benefit. Instead of writing only “users can share a printer”, explain the consequence: several users can access one device, reducing duplicated equipment and maintenance costs.
Exam tip
Build an explanation as network feature → practical consequence. For example, a network allows central file storage, so authorised users can access the same current files and backups can be managed in one place.
Local and wide area networks
Networks can be classified partly by the area they cover. A stronger comparison also considers who manages the infrastructure, what connects directly to the network and how communication links are supplied.
Wide area network (WAN): a network linking geographically separated locations, often through communication links supplied by another organisation.
| Comparison point | LAN | WAN |
|---|---|---|
| Geographical scope | Normally limited to one home, building, campus or site | Links separate sites across a city, country or larger region |
| Control of infrastructure | Usually installed and managed by the person or organisation using it | Often relies on links leased from a telecommunications or network provider |
| Directly connected systems | User devices, servers and shared peripherals connect to the local network | Usually links complete local networks, offices or branches |
| Typical links | Ethernet cabling and wireless access within the site | Long-distance fibre, dedicated circuits or other provider-managed links |
| Typical purpose | Share resources and services within a local site | Allow geographically separated sites to communicate and use common services |
Applying the distinction
Imagine a sports academy with three campuses. The computers, printers, servers and wireless access points inside each campus form a LAN. The managed communication links carrying data between the campuses form the organisation's WAN. The complete system therefore contains several LANs connected by a WAN.
Common mistake
A WAN is not simply “a LAN with more computers”, and a network does not become a WAN merely because it has Internet access. The distinction concerns geographical reach and the infrastructure used to connect locations.
Exam tip
Compare the same characteristic on both sides. For example: a LAN is normally controlled within one site, whereas a WAN often uses externally supplied links to connect separate sites.
Interactive enrichment: how network use widened
Use the timeline to explore how the reasons for networking broadened as computing moved from shared central systems to local resource sharing and then to widespread access across interconnected networks.
Practice
Try these questions
- Explain two benefits of connecting the computers in a photography studio.
- Explain how sharing one specialist printer could benefit a small design company.
- Compare a LAN and a WAN using geographical scope and control of infrastructure.
- A company has a LAN at each of four offices. Explain how a WAN could be used.
- A university has several buildings on one campus and a second campus 60 kilometres away. Identify where LANs and a WAN would be used.
- Explain why Internet access alone does not determine whether a network is a LAN or a WAN.
Review
Key ideas
- Networks support communication and the sharing of data, hardware and services.
- A strong explanation links a network feature to its practical consequence.
- A LAN operates within a limited location and is normally controlled locally.
- A WAN links geographically separated locations and often uses provider-managed links.
- A large organisational network may contain several LANs connected by a WAN.
Quick self-check
- Can I explain a network benefit rather than merely name a shared resource?
- Can I compare LANs and WANs using more than geographical size?
- Can I classify the networks used in a multi-site organisation?