OSI Layer Diagram - buaamer81/IT130-Networking-Wiki GitHub Wiki
OSI Layer Diagram
📘 Visual Overview of the OSI Model
The OSI (Open Systems Interconnection) Model is a conceptual framework used to understand network communication.
It divides network functions into seven distinct layers, each with its own responsibilities and protocols.
🖼️ OSI Model Diagram
🧱 OSI Layers (Top to Bottom)
| Layer | Name | Function |
|---|---|---|
| 7 | Application | Interface for user apps (e.g., HTTP, FTP) |
| 6 | Presentation | Data formatting, encryption, compression |
| 5 | Session | Manages sessions (start, control, end) |
| 4 | Transport | Reliable/unreliable delivery (TCP/UDP) |
| 3 | Network | Logical addressing & routing (IP) |
| 2 | Data Link | MAC addressing, framing |
| 1 | Physical | Transmission of raw bits (electrical/light/radio) |
📎 Mnemonics
- Top to Bottom: All People Seem To Need Data Processing
- Bottom to Top: Please Do Not Throw Sausage Pizza Away
📚 Related Pages
- OSI Model Overview
- Encapsulation Explained
- TCP/IP Model Overview
- PDU at Each Layer
- Protocols and Devices Per Layer
🔁 Referenced In
- Layer 1: Physical Layer
- Layer 2: Data Link Layer
- Layer 3: Network Layer
- Layer 4: Transport Layer
- TCP/IP vs OSI Comparison Table
Return to: Chapter 2