|  | 2.2 | The OSI Reference Model
| 2.2.1 | The purpose of the OSI reference model

The OSI reference model is the primary model for network communications. Although there are other models in existence, most network vendors, today, relate their products to the OSI reference model, especially when they want to educate users on the use of their products. They consider it the best tool available for teaching people about sending and receiving data on a network.

The OSI reference model allows you to view the network functions that occur at each layer. More importantly, the OSI reference model is a framework that you can use to understand how information travels throughout a network. In addition, you can use the OSI reference model to visualize how information, or data packets, travels from application programs (e.g. spreadsheets, documents, etc.), through a network medium (e.g. wires, etc.), to another application program that is located in another computer on a network, even if the sender and receiver have different types of network media.

In the OSI reference model, there are seven numbered layers, each of which illustrates a particular network function. This separation of networking functions is called layering. Dividing the network into these seven layers provides the following advantages:

- It breaks network communication into smaller, simpler parts.
- It standardizes network components to allow multiple-vendor development and support.
- It allows different types of network hardware and software to communicate with each other.
- It prevents changes in one layer from affecting the other layers, so that they can develop more quickly.
- It breaks network communication into smaller parts to make learning it easier to understand.

| Web Links
| The OSI Seven Layers Model