In computer networking fundamentals, which one of the following items is typically not required to build or operate a Local Area Network (LAN) within an office or campus environment?

Introduction / Context:
A Local Area Network (LAN) interconnects devices such as PCs, printers, and servers across a small geographic area like a room, floor, or building. Understanding which components are essential to a LAN—and which belong to wide-area or Internet access—is a foundational skill for IT support and exam preparation.

Given Data / Assumptions:

• Scope is a LAN: limited to a local site, short distances, and high-speed links.
• Typical LAN media include twisted pair, fiber, and sometimes radio (WLAN).
• End devices: computers, printers, access points, switches.

Concept / Approach:
A modem (modulator/demodulator) converts digital signals to analog waveforms (and back) for carriage over legacy telephone circuits or other carrier facilities. That function is associated with WAN or Internet edge connectivity, not with the internal switching of a LAN. Inside a LAN, devices connect through Ethernet switches using digital signaling over copper or fiber; no analog conversion is required.

Step-by-Step Solution:

Verification / Alternative check:
In a common setup, the modem sits at the Internet/WAN edge (e.g., DSL/cable/4G) and connects to a router/firewall; internal LAN segments remain entirely digital and switched without modulation/demodulation steps.

Why Other Options Are Wrong:

Common Pitfalls:
Confusing internal LAN components with Internet-edge equipment; assuming Wi-Fi always removes the need for cabling (switch uplinks and PoE still use cables).

Final Answer:
Modem.