An In-depth Look at the 7 Layers Of The OSI Model

The first thing you need to know about the OSI Model is what it stands for. Open Systems Interconnection Model is a concept used to explain the workings of networking systems. The history of the OSI Model dates back to the early 1980s.

Each of the seven layers of the OSI model has a function of its own. Overall, the model examines a network to detect and pinpoint problems. The layers are helpful tools in helping tech vendors teach their customers which product works best for them.

OSI Model Design Description from the Top

Each of the levels in the OSI ideal has a specific function. They are all more interconnected in a way and rely on each other to perform their roles. Understanding how the layers are interconnected is essential to help learn how a network works.

Here is a breakdown of the seven layers of OSI Model.

7. Application

First up in this description is the application layer that handles data from the users. Besides receiving information, it is also responsible for displaying incoming data to the user.

The application layers are a sort of interface that facilitates communication in web browsers like Google Chrome and Firefox and email clients.

It utilizes protocols that allow information exchange between software and data users. Examples of protocols used in these layers are Hypertext Transfer Protocol and Post (HTTP) Office Protocol (POP).

6. Presentation

Unlike the Application Layer, the presentation layer is independent of data representation. Its primary function is representing the application format to network format and vice versa.

For it to function correctly, there must be an agreement with the syntax of the application. It’s where encryption and decryption take place for data required by the application layer. Presentation is like an assistant for the application layer.

5. Session

A session gets created every time two computers or network devices want to communicate with one another. The session layer is responsible for creating sessions. This level works on setup, coordination, and termination of communication between devices.

The session level ensures enough time to transfer data between devices before a session closes. This level is also responsible for the synchronization of data transfers with checkpoints.

4. Transport

The transport level is an intermediary for data transfer between systems and hosts. All data transfers and error checks happen here. Data gets broken down into segments to allow transfers.

Also, it regulates the size of those segments and sequencing before transfer. Data transfers happen at a rate that matches the connection speed of the receiving device. If data reception is incorrect, the transport level can request a second transfer.

3. Network

This level of the OSI model facilitates data transfer between two different networks. The two devices exchanging data have to be on various networks for transfers to happen. During transfers, the network level routes, finding the best path for data to reach its destination.

For transfers to happen, the network layer further breaks down the segments from the transport layer. The smaller pieces are called packets. The network-level works to reassemble the broken components after completing transfers.

2. Data Link

The data link layer terminates the connection between two networks with physical contact. Also, it’s responsible for handling error corrections from the physical layer. The packets from the network layer get broken further into frames at this level.

Two parts make up this level. One of those parts is the Logical Link Control (LLC), whose role is to identify network protocols, check errors, and match frames. The second part is the Media Access Control (MAC), which connects devices and selects permissions for data transmissions.

1. Physical

The physical layer is the lowest level of the OSI Model. It plays a transmission role involving physical equipment like cables and switches.

Data conversion also takes place here, where data gets converted into bits. For the physical level to function correctly, there has to be an agreement between the physical layers of both devices.

Relevance of the OSI Model

The OSI model is beneficial when it comes to troubleshooting network problems. The modern internet does not use the OSI model, but some parts depend on it to troubleshoot.

Its application area ranges from solving laptop connection problems to repairing web sites. The OSI models save you unnecessary work by detecting specific problems and assigning them to a particular layer for solving. Detecting problems with a network is a general advantage of the OSI Model.

Network users and operators can use the model to find out the hardware and software they will need to build their network. Additionally, operators can understand the process going on within a network to facilitate communication.

Manufacturers and software vendors also benefit from the OSI Model in the following ways.

  • It helps vendors network layer their products to be compatible with
  • The model helps them design devices and software that are interoperable.
  • The model helps assign parts of the network vendor products.

Frequently Asked Questions

Q: What are the advantages of the seven layers of the OSI model?

A: The main advantage of the OSI model is that it separates services, interfaces, and protocols. It is flexible, which allows a change of protocol in each layer to meet the needs of a network.

Q: How is the OSI Model useful in the industry?

A: The seven-layer OSI Model plays a significant role in helping to visualize and communicate between networks. It also helps troubleshoot and isolate network problems.

Q: Which part of the OSI Model is the physical part?

A: The physical layer is the lowest level of the OSI Model, which sends bits from one device to another.

Application of the OSI Model on a Network

The OSI Model provides a standard platform for different computer systems to communicate. It is like a universal language for computer networking.

The workings of the OSI Model build on the concept of splitting up a communication system. As a network operator, you will have to use the OSI Model to help make work easier.

Kraft Technology can help you understand the workings of the OSI Model. Connect with us For more information,