Networking fundamentals
⏱ ~3-min readAceMark Guide
What this topic is really about
In a star topology, every node connects to a central switch or hub, so a single cable failure affects only one device. A bus shares one backbone, a ring passes traffic device-to-device, and a mesh interconnects many nodes for redundancy.
A router forwards packets between networks using Layer 3 IP addressing and routing tables. A switch forwards within a LAN at Layer 2, a hub repeats signals at Layer 1, and a repeater simply regenerates a signal to extend distance.
See the mechanism
Switches make forwarding decisions on Layer 2 MAC addresses. A diagram for this topic isn't available yet — the worked example below walks the same reasoning step by step.
An exam-style question, fully explained
At which OSI layer does a switch primarily forward traffic?
- Identify what the question tests: At which OSI layer does a switch primarily forward traffic.
- Switches make forwarding decisions on Layer 2 MAC addresses.
- Hubs operate at Layer 1, routers operate at Layer 3, and Layer 4 deals with TCP/UDP segments.
Traps the examiner sets
- Knowing common ports is a core Network+ objective.
Test your recall
Answer each from memory — you'll see instantly whether you're right and why.
Run a focused 10-question mini-mock on Networking fundamentals and see it stick.
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