The reference model for computer networks is the Open Systems Interconnection (OSI) model, which was developed by the International Organization for Standardization (ISO). It is a conceptual model to which the computer networks, makers can refer to rather than a precise description of a real network. In the ISO/OSI model, every node of the network can be sketched as a hierarchical structure of seven levels, as shown in the following diagram:
Functional layers in the ISO/OSI model
The functional layers in the OSI model are explained as follows:
- The first level, starting from the bottom, is level 1, or the physical level. This includes the mechanical and electrical connections between the nodes, together with the software drivers for the communication ports. The features of this level establish some parameters of the network, such as the speed and the transmission...