Role of OSI Model in IoT Projects

If you are using a ready-built TCP/IP WiFi or Ethernet library such as already exist for many MCUs and programming systems, it's not really relevant - hardly more than using an internet connected program on a desktop, laptop or mobile phone.

It does matter if you are writing your own library/stack, or device drivers etc.

eg. The last "connected" device I put together mainly used the ESP2866 WiFi capability and an MQTT library for communications.

I did not have to look at any lower level code at all, for that side of things.

rjenkinsgb said:

It does matter if you are writing your own library/stack, or device drivers etc.

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Imagine we're creating project where we deploy devices in different cities to collect temperature and humidity data.

In this project, each device includes temperature sensors and an ESP2866. These devices gather data and send it to a central server via a Wi-Fi router. The server then analyzes this data and provides real-time updates through a web application or Android app.

Additionally, Information that the sensors operate on the I2C protocol, and the MQTT protocol is used to transmit temperature data between clients and the server.

I'm looking help to understand the role of the OSI model layers in this theoretical project. Could you please explain how each layer of the OSI model relates to the functionalities of our weather monitoring system?

It is now and probably always was completely irrelevant. Most engineers realized significant performance improvements by ignoring it altogether and merging the functions of the layers until it was all a blur. Don't waste your time with it.

Papabravo said:

It is now and probably always was completely irrelevant. Most engineers realized significant performance improvements by ignoring it altogether and merging the functions of the layers until it was all a blur. Don't waste your time with it.

Click to expand...

When tackling a project like this, what would be your general approach for developing code from scratch. my general approach is to start from the bottom to top , so the bottom-to-top method sounds like a solid plan. Given the server-client setup, we'll need programs for both sides.

For the client side, let's begin by connecting the temperature sensor to the ESP8266 board. Writing I2C code to get temperature and humidity data.

Once we have that set up, I don't know further development of client program step by step

You learn more by doing, than by reading in most cases.

Have a look at this for a starter - it has the WiFi and MQTT included already; just remove the "Roomba" serial interface bits and add whatever sensors you need.