Unfortunately, I couldn’t understand the OSI Layers at University. I read our books and also our teachers said what the OSI is, but no one show me where the OSI using in real life. After I started my profession, I realize that how important is the understanding OSI model and get information about which layer is using where with hands on experiences.
We can say that OSI is explain us how data transfer one point to another and which stations pass during this transfer period. The transfer function can be easily understand with separating the transfer path at the 7 main layers.