OSI - OSI Model Lesson

OSI Model

Standards are documented agreements containing technical specifications or other precise criteria that stipulate how a particular product or service should be designed or performed. Many different industries use standards to ensure that products, processes, and services fit their purposes. Like when construction industries follow standards to ensure safety and accessibility, such as defining appropriate dimensions for wheelchair ramps. If you think about the wide range of hardware and software used today, standards are even more important in the world of networking. Without standards it would become difficult to design a network.

The International Standards Organization (ISO) developed the Open Systems Interconnection (OSI) model in the early 1980s to describe how network protocols and components work together. It divides network functions into seven layers, and each layer represents a group of related specifications, functions, and activities.The OSI model is used for the transfer of data over a network which moves through different layers.

Essentially, the OSI model describes a networking framework and how information from a software application in one computer moves through a network to a software application in another computer.

The OSI Model works in a hierarchy, assigning tasks to all seven layers. Each layer is responsible for performing assigned tasks and transferring completed tasks to the next layer for further processing. Thorough understanding of the OSI model is important to be more effective in network design and troubleshooting.

Now take a look at the 7 layers of the OSI model and how information from a software application in one computer moves through a network to a software application in another computer.

Click here to view an interactive lesson on Open Systems Interconnection (OSI) produced by NCYTE Center. Links to an external site.

Let’s look at a brief recap of the layers of the OSI model. It is important to remember that this model (OSI) is essential to network communication.

OSI Model Layers Application provides the services to the user, presentation is responsible for translation, compression and encryption, session is used to establish, manage, and terminate the sessions, transport provides reliable massage delivery from process to process, network is responsible for moving the packets from source to the destination, data link is used for error free transfer of data frames, and physical provides a physical medium through which bits are transmitted.

Now it is time for a Self-Assessment.

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