Hands-On System Programming with Go

OSI model

The Open Systems Interconnect (OSI) model is a theoretical model that dates back to the early 1970s. It defines a standard of communication that works regardless of the physical or technical structure of a network, with the goal of providing interoperability for different networks. 

The model defines seven different layers, numbered from one to seven, and each layer has a higher level of abstraction to the previous one. The first three layers are often referred to as media layers, while the other four are the host layers. Let's examine each, one by one, in the following sections.