Which device links two homogeneous packet-broadcast local networks (e.g., two Ethernet segments) and forwards frames based on MAC addresses?

Introduction / Context:
LAN interconnection can be done at different layers. Devices that operate on MAC addresses and forward frames between similar LANs are distinct from repeaters (physical) and routers (network layer).

Given Data / Assumptions:

• Networks are homogeneous packet-broadcast LANs (e.g., Ethernet to Ethernet).
• Forwarding decision is based on MAC addresses.
• Goal is segmenting collision domains and learning addresses.

Concept / Approach:
A bridge (including modern multi-port switches) builds a MAC address table by learning source addresses and forwards frames to the correct segment, reducing unnecessary traffic and isolating collisions while preserving a single broadcast domain (unless VLANs are used).

Step-by-Step Solution:
Recognize same-type LANs being interconnected (homogeneous).Match to a device that understands layer-2 addresses.Select “bridge” as the correct device class (today commonly implemented as a switch).

Verification / Alternative check:
IEEE 802.1D bridges perform transparent bridging using MAC learning and spanning tree to prevent loops.

Why Other Options Are Wrong:
Hub: Physical-layer repeater that floods signals; no MAC learning.

Repeater: Only regenerates signals; no frame filtering.

Gateway: Heterogeneous inter-protocol translation at higher layers.

Router: Connects different IP subnets at layer 3, not layer 2 bridging (though both interconnect networks).

Common Pitfalls:
Equating modern Ethernet “switches” with routers; a typical switch is a multi-port bridge.

Final Answer:
bridge