OSI Model

*Why do we need the OSI Model?

·         To address the problem of networks increasing in size and in number, the International Organization for Standardization (ISO) researched many network schemes and recognized that there was a need to create a network model

·         This would help network builders implement networks that could communicate and work together

·         ISO therefore, released the OSI reference model in 1984. 

* Don’t Get Confused.

ISO - International Organization for Standardization

OSI - Open System Interconnection

IOS -  Internetwork Operating System

To avoid confusion, some people say “International Standard Organization.”

*The OSI Reference Model

*OSI Model

*OSI Layers :

Layer 7 - The Application Layer

Layer 6 - The Presentation Layer

Layer 5 - The Session Layer

Layer 4 - The Transport Layer

Layer 3 - The Network Layer

  

Layer 2 - The Data Link Layer

Layer 1 - The Physical Layer