No discussion of networks would be complete without mentioning the Open Systems Interconnection (OSI) reference model. Early in their careers, network engineers hear references to Layer 2 and Layer 3 devices. These terms are referring to the layer of the OSI model on which a device works or the layer of the model that best describes its core functionality.
The OSI model for networking was originally designed in 1978 to set communications standards for connecting dissimilar devices. The 1984 revision has become the international guide for networking.
Although every piece of network equipment and network-enabled ...