WAN – know that these are often under collective or distributed ownership.

The idea

A wide area network (WAN) spans a large geographical area, linking sites such as offices in different cities or countries, typically using infrastructure the organisation does not own itself, such as leased telecoms lines or the internet. Because building and running links across such distances is costly, WANs are often not owned by a single organisation. Instead they are commonly under collective ownership, where several organisations share and jointly fund the infrastructure, or distributed ownership, where different parts of the network are owned and managed by different parties, for example a telecoms provider owning the backbone while a business owns only its local routers. This shared arrangement spreads cost and responsibility.

What earns the marks

• States that a WAN covers a large geographical area, connecting sites across cities, countries or continents.
• Explains that WAN infrastructure is often too costly for one organisation to build and own alone.
• Identifies collective ownership as several organisations sharing and jointly funding or managing the WAN.
• Identifies distributed ownership as different parts of the WAN being owned or managed by different parties, such as a telecoms provider and a business.
• Distinguishes a WAN from a LAN, which is typically owned and managed by a single organisation on one site.
• Applies the ownership idea to a scenario, for example recognising that a company using leased lines does not own the whole network.

Common mistakes and how to put them right

• Assuming a WAN is always owned by one company.

  Put it right: Is that WANs are often under collective or distributed ownership because of cost and scale.

• Confusing a WAN with a LAN.

  Put it right: Is that a LAN is usually a single site owned by one organisation, whereas a WAN spans large distances and is often shared.

• Thinking distributed ownership means the network has no owner.

  Put it right: Is that ownership is split between different parties, not absent.

Exam tips

• Read the scenario carefully and ask who owns each part of the network before choosing an option.
• Link the ownership idea to the large geographical scale, since distance is why shared ownership is common.
• Eliminate options that describe a single-site, single-owner network, as these describe a LAN rather than a WAN.