Computer Networks - The OSI (Open Systems Interconnection) model
Definition: The OSI model defines internetworking in terms of a vertical stack of seven layers. The upper layers of the OSI model represent
software that implements network services like encryption and connection management. The lower layers of the OSI model implement more primitive,
hardware-oriented functions like routing, addressing, and flow control.
The OSI model was introduced in 1984. Although it was designed to be an abstract model, the OSI model remains a practical framework for today's key
network technologies like Ethernet and protocols like IP.
The OSI model should be used as a guide for how data is transmitted over the network. It is an abstract representation of the data pathway and should
be treated as such.
The OSI model was specifically made for connecting open systems. These systems are designed to be open for communication with almost any other system.
The model was made to break down each functional layer so that overall design complexity could be lessened. The model was constructed with seven layers
for the flow of information. These are: