ITPEC IP April 2019 Question 33

Head office and branch offices linked over a service provider's lines — a WAN connects distant sites through a communications service provider's lines.

Within a building or its premises, a company can lay its own cables; that network is a LAN. To reach sites in other districts or cities, a company cannot lay cable across public land, so it rents lines from a communications service provider, such as a leased line, IP-VPN or wide-area Ethernet. A network built on those lines is a WAN.

Answer (c)

Why not others:

• •(a) — buildings within the same premises on the company's own lines are still a LAN, however many buildings it spans
• •(b) — floors of one building form a LAN
• •(d) — PCs on one floor form a LAN

Key rule: Tell a LAN from a WAN by the lines: a LAN stays within the premises on the organisation's own cabling, while a WAN joins distant sites through a carrier's lines.

Networks · AI-written, may contain errors