OSI model quiz
The fastest way to lock in the seven layers: a protocol, device, or function appears, and you pick which OSI layer it belongs to. Instant feedback, a streak counter, and unlimited questions. No account, nothing to install.
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OSI model FAQ
What are the 7 layers of the OSI model?
From bottom to top: Layer 1 Physical (cables, bits, signaling), Layer 2 Data Link (MAC addresses, switches, frames), Layer 3 Network (IP addresses, routers, packets), Layer 4 Transport (TCP/UDP, ports, segments), Layer 5 Session, Layer 6 Presentation (encryption, formatting), and Layer 7 Application (HTTP, DNS, SSH). A common mnemonic is “Please Do Not Throw Sausage Pizza Away.”
How do I remember which layer something belongs to?
Anchor on the four layers the CCNA leans on: Physical is anything you can touch (cables, bits); Data Link is the local switch world (MAC, frames, VLANs); Network is routing between networks (IP, routers, packets); Transport is TCP/UDP and port numbers. Almost every named protocol (HTTP, DNS, DHCP, SSH) lives at the Application layer. Drill the rest with the quiz above.
Is the OSI model on the CCNA exam?
Yes — Network Fundamentals expects you to know the OSI and TCP/IP models and to place protocols, devices, and PDUs at the right layer. It's also the mental map you'll use to troubleshoot for the rest of your career: is the problem physical (Layer 1), switching (Layer 2), routing (Layer 3), or an application/port issue (Layer 4/7)?
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Understand the layers, don’t just memorize them
The OSI model clicks when you see what happens at each layer — read the explainer, then drill it here.