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Mohcin Bounouara

Thoughts about software engineering and life

Backend Engineering Solidify: An Overview of the OSI Model

In my pursuit of solidifying my backend knowledge, I want to share with you an overview of the OSI model as I understand it. This post serves as a reference for me to revisit and update later.

The OSI Model, which stands for Open Systems Interconnection Model, is a conceptual framework that defines the transformation of the data. This model organizes the flow of data in a communication system into seven layers, representing sequential steps through which data passes.

Layer 7: This is the application layer. When you input a GET request into your browser, various elements such as IDs, strings, and more are included in this GET request.

Layer 6: Moving to the presentation layer, this is where encryption, particularly for HTTPS, takes place.

Layer 5: The session layer comes next, establishing a session tag ID when initiating a connection.

Layer 4: At the transport layer, the requests transfer data using segments and specific ports, often referred to as the destination.

Layer 3: The network layer, or the IP protocol, takes the segment and attaches it to an IP address.

Layer 2: The data link layer utilizes MAC addresses to identify the destination of the page.

Layer 1: The physical layer is the bits and binary transmission 

Understanding each layer of the OSI model is crucial for comprehending the intricacies of data communication in backend engineering. This conceptual framework provides a systematic approach to visualizing the processes involved in transforming and transmitting data across a network. Maybe I’ll come up with examples later for this blog post.