Networking - TCP/IP Model
What is the TCP/IP Model?
The TCP/IP model (Transmission Control Protocol/Internet Protocol) is a set of rules that allow computers to communicate over the internet.
Think of it like a postal system for the internet – it breaks down data into small packets, sends them across networks, and reassembles them at the destination.
TCP/IP Model Has 4 Layers (from bottom to top):
| Layer No. | Layer Name | What It Does |
|---|---|---|
| 1 | Network Access (or Link) | Moves data over physical network (cables, Wi-Fi) |
| 2 | Internet Layer | Finds the best path to send data (using IP addresses) |
| 3 | Transport Layer | Ensures data is sent reliably and in the correct order |
| 4 | Application Layer | Interacts with software apps like web browsers or email apps |
Quick Look at Each Layer
1. Network Access Layer
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Deals with physical devices like routers, switches, and cables.
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Responsible for sending data to nearby devices on the same network.
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Works with technologies like Ethernet or Wi-Fi.
2. Internet Layer
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Uses the IP (Internet Protocol) to give every device an address.
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Chooses the best route for data to travel across networks.
3. Transport Layer
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Uses TCP (for reliable delivery) or UDP (for faster delivery, like video streaming).
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Ensures no data is lost or mixed up during transmission.
4. Application Layer
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Where users interact with the network through apps like:
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Web browsers (HTTP/HTTPS)
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Email clients (SMTP, POP3)
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File transfer tools (FTP)
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