Gary Minato's Cisco Pages
The OSI Reference Model

The OSI reference model was designed by the ISO to be the primary model for network communications. The OSI reference model allows you to view the network functions that occur at each layer. The OSI reference model is a framework that is used to understand how information travels throughout a network. It can be used to visualize how data travels from an application program at Layer 7 on one computer, down through the other layers, through a network medium (Layer 1) to another computer where it travels up the layers to that computers application layer.

The OSI model allows for:

  • Modular engineering
  • Reduces complexity
  • Accelerates evolution
  • Standardizes interfaces
  • Interoperable technology
  • Simplifies learning

This website will provide you with the definition of each layer and provide details of the hardware, software and technologies that exist at each layer.

Port Numbers | ISDN | ACL

LAYER 1 | LAYER 2 | LAYER 3 | LAYER 4 | LAYER 5 | LAYER 6 | LAYER 7

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