OSI MODEL - History, Origin, Purpose

The International Standards Organization (ISO) developed a theoretical model of how networks should behave and how they are put together. This model is called the Open Standards Interconnect (OSI) Model. The "ISO OSI Model" was developed because it appeared that IBM was going to patent the design of their SNA networks so that no one else could use IBM's design model for networking. The ISO OSI model is used throughout the network, internet and telecom industries today to describe various networking issues. The OSI model is also of use in a learning or training environment where a novice can use it as a point of reference to learn how various technologies interact, where they reside, what functions they perform and how each protocol communicates with other protocols.

The ISO's Open Standards Interconnect document series defines a model for networking which specifies:

  • How information should be handled when being transported over a network.
  • How software should interact with the network.
  • Layers at which specific networking functions are performed.
  • Layer specific functions should be invisible to the layer above it and below it.
  • The method of communication at the boundaries between layers.


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