My understanding of it thus far is that the OSI Model is a layer-based model that explains how computers communicate with eachother. Keep in mind that It's a theoretical representation or explanation of the process that data goes through as it moves from one node on the network to another. It's not a physical thing.
The 7 layers are, from the 7th layer down:
7. Application - Facilitates communication between software applications and the lower layers.
6. Presentation - Accepts data from Application Layer and formats it so that one type of application and host can understand data from another type of application and host. (...wat?)
5. Session - The layer responsible for coordinating and maintaining communications between two nodes.
4. Transport - Accepts data from the Session layer and manages the end-to-end delivery of data, meaning they can ensure they data is transferred from point A to point B reliably, in the correct sequence, without erros.
3. Network - Translates network addresses into their physical counterparts and decides how to route data from the sender to receiver.
2. Data Link - Divides data it receives from the Network layer into distinct "frames" that can then be transmitted by the Physical layer.
1. Physical - Accepts frames from the Data Link layer, and generates signals as changes in voltage at the Network Interface Card.
I've finished all the reading material and simulation material, but some of this stuff just doesn't seem to want to stick in my head. Anyone have any tips or suggestions for this?




