Which connectivity device extends a network on a purely mechanical/passive basis (no signal regeneration or frame switching), simply distributing the electrical signal to multiple ports?

Introduction / Context:
Network extension can occur at different OSI layers and with varying levels of intelligence. Some devices merely distribute signals, while others regenerate, filter, or forward frames based on MAC or IP addresses. Identifying the most primitive, passive form clarifies the spectrum from simple cabling aids to full-fledged switches and routers.

Given Data / Assumptions:

• “Purely mechanical/passive” means no amplification, regeneration, or decision-making.
• The device fans out a signal to multiple ports, like a wiring concentrator.
• It contrasts with active hubs (repeaters), switches (bridges), and routers (layer-3 forwarding).

Concept / Approach:
A passive hub operates like a simple signal splitter on a shared medium; it does not regenerate or reshape the signal. An active hub (multiport repeater) regenerates bits. A switch (multiport bridge) forwards frames intelligently using MAC learning. A router forwards at layer 3, and a gateway typically performs protocol translation/mediation. Therefore, the only device matching “purely mechanical/passive” is the passive hub.

Step-by-Step Solution:

Verification / Alternative check:
Historical Ethernet topologies (10BASE-T) occasionally used passive concentrators in lab/demo setups, while production deployments favored active hubs or switches for signal integrity—underscoring the passive hub's purely mechanical nature.

Why Other Options Are Wrong:

• Active hub: electrically regenerates the signal.
• Switch: forwards frames based on MAC addresses.
• Router: forwards packets based on IP addressing and routing tables.
• Gateway: performs higher-layer/protocol conversions.

Common Pitfalls:
Using “hub” generically; not all hubs are passive. Many hubs in practice were active repeaters, but the question explicitly requires a purely passive device.

Final Answer:
Passive hub