The OSI Model

HISTORY OF THE OSI MODEL

In order to simplify the study and implementation of the necessary architecture, the ISO (International Standards Organization) created the OSI reference model to achieve international standardization of protocols. This model deals with the Interconnection of Open Systems for communication and is divided into 7 layers, with "layer" being understood as an entity that performs a specific function in itself.

The principles that were applied for its division into layers are:

1. A layer should be created whenever a different level of abstraction is needed.

2. Each layer must perform a well-defined function.

3. The function of each layer should be chosen with the definition of internationally standardized protocols in mind.

4. Layer boundaries should be chosen to minimize the flow of information across interfaces.

5. The number of layers should be sufficient so that different functions do not have to be lumped into the same layer, and small enough so that the architecture does not become unmanageable.