The document discusses the OSI model, which structures network communication into 7 layers - physical, data link, network, transport, session, presentation, and application. It provides an overview of the functions of each layer, from the physical layer which transmits raw data up to electrical signals, to the application layer which provides services for file transfers, printing and other applications. Diagrams and examples are included to illustrate how data moves through each layer of the OSI model during network communication.

1. Chapter 3 OSI Model The model Functions of the layers My notes for DataCom :: @nkur 

2. Figure 3-1 My notes for DataCom :: @nkur  OSI Model

3. Figure 3-2 My notes for DataCom :: @nkur  OSI Layers

4. Figure 3-3 My notes for DataCom :: @nkur  An Exchange Using the OSI Model

5. Figure 3-4 My notes for DataCom :: @nkur  Physical Layer

6. Figure 3-5 My notes for DataCom :: @nkur  Data Link Layer

7. Figure 3-6 My notes for DataCom :: @nkur  Data Link Layer Example

8. Figure 3-7 My notes for DataCom :: @nkur  Network Layer