OSI Model Layer (Part-2)

The Open Systems Interconnection (OSI) model comprises seven layers.

We are continuing from Part 1.

4. Transport Layer: The transport layer (Layer 4) of the OSI model helps manage data transfer between devices. It makes sure data is split into smaller parts, checks for errors, and controls the flow of information. It uses two main protocols: TCP (which ensures a reliable connection) and UDP (which sends data quickly without confirming delivery). This layer also organizes the data into segments, tracks their delivery, and reassembles them if needed, ensuring everything gets to the right place.

OSI Model Layer 4 — Transport Layer

Comparing TCP vs UDP

TCP vs UDP Protocols

The 3-way handshake operates at Layer 4 (Transport Layer) of the OSI model. It is part of the TCP (Transmission Control Protocol) process used to establish a reliable connection between a client and a server. Three steps-

1. SYN: The client sends a synchronization request to the server.
2. SYN-ACK: The server acknowledges the request and sends back a synchronization acknowledgment.
3. ACK: The client acknowledges the server’s response, completing the connection setup.