TCP IP Four Layer Model Guide | Generated by AI
Question Content
This question tests the four-layer structure of the TCP/IP reference model.
TCP/IP Reference Model - Four Layers
From bottom to top, the layers are:
| Layer | Name | Main Functions | Main Protocols |
|---|---|---|---|
| Layer 4 | Application Layer | Provides user application services | HTTP, FTP, SMTP, DNS, Telnet, etc. |
| Layer 3 | Transport Layer | End-to-end communication | TCP, UDP |
| Layer 2 | Internet Layer | Routing and logical addressing | IP, ICMP, IGMP |
| Layer 1 | Network Interface Layer | Physical transmission and hardware addressing | Ethernet, PPP, WiFi |
Analysis of All Options
| Option | Explanation |
|---|---|
| A | Presentation Layer - Belongs to OSI seven-layer model, not TCP/IP model |
| B | Session Layer - Belongs to OSI seven-layer model, not TCP/IP model |
| C | Physical Layer - Belongs to OSI seven-layer model, not TCP/IP model |
| D | Application Layer - Top layer of TCP/IP model ✓ |
Key Distinction
TCP/IP Model vs OSI Model:
TCP/IP Model (4 layers) OSI Model (7 layers)
Application Layer ←→ Application, Presentation, Session Layers
Transport Layer ←→ Transport Layer
Internet Layer ←→ Network Layer
Network Interface Layer ←→ Data Link Layer, Physical Layer
Your Answer
✓ D Application Layer - Completely Correct!
Correct Answer
✓ D Application Layer
Justification:
- The TCP/IP reference model has 4 layers in total
- From bottom to top: Network Interface Layer → Internet Layer → Transport Layer → Application Layer
- The Application Layer provides various network services required by user applications
Learning Tips:
- Master the correspondence between the TCP/IP four-layer model and the OSI seven-layer model
- Do not confuse the layer concepts of the two models
- Remember the characteristics of the TCP/IP model: it simplifies the OSI seven-layer model into four layers