OSI Model Demystified: Open Systems Interconnection
by Yuvi K - December 16, 2023
OSI Model Demystified: Open Systems Interconnection Model(OSI)
The Open Systems Interconnection model (OSI Model) is the industry-standard architecture for network protocols and network communication. The OSI model is a key component of the internet and provides the foundation for how services such as email and the web work. OSI model is an increase of two processes can share data – a sender and a receiver process. With the seven layers of the OSI model and the understanding of data transmission between process, we can safely say that the OSI model is the backbone of computer networks and internet protocols.
A Layman’s Understanding of the OSI Model
In a nutshell, the OSI (Open Systems Interconnection) model is an architecture of different protocols and layers that are used for sending data between two processes or machines. An example of this is when an email is sent from sender to receiver. Here, the two processes involved are the sender and the receiver. In this process, the sender’s machine first has to convert the email into a packet and then send it to the receiver.
The OSI model is composed of seven layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application. Each of these layers has a specific purpose and a specific protocol associated with it. The physical layer is responsible for the physical connection between the two processes. The data link layer involves network addressing, error detection, and synchronization of data communication. The network layer is where data is routed between two processes. The transport layer provides a reliable and guaranteed flow of data. The session layer provides synchronization between two processes. The presentation layer provides data transformation. And finally, the application layer is the layer at which humans can interact with the network.
How Does the OSI Model Work?
At a high level, the OSI model works in the following manner:
1. The sender process converts the data (email, web page, etc) into a packet of data.
2. This packet of data is then sent to the physical layer of the OSI model.
3. The physical layer will then transmit the data to the data link layer.
4. At the data link layer, network addressing and error detection will occur.
5. The packet of data will then be sent to the network layer, where it will be routed between two processes.
6. The packet of data will then be sent to the transport layer, where a reliable and guaranteed data flow will be established.
7. The packet of data will then be sent to the Session layer, where it will be synchronized between two processes.
8. The packet of data will then be sent to the Presentation layer, where it will be transformed into a different format.
9. Finally, the packet of data will be sent to the Application layer, where the data can be interpreted and used (in the case of email, for example).
How the OSI Model Benefits Computer Networks
The OSI model provides a number of benefits to computer networks. By establishing a framework for how data is transmitted between two processes, the OSI model makes it easier for developers and network engineers to develop and deploy applications and services.
Additionally, the OSI model ensures that data is transmitted securely and reliably between two processes. By implementing different layers of security, such as encryption, authentication, and authorization, the OSI model ensures that data is not lost or corrupted during transmission.
Finally, the OSI model makes it easier to troubleshoot issues with computer networks. By having a standard architecture that is easily understood, network engineers can quickly identify where an issue is located and work to resolve the issue.
Conclusion
The OSI model provides an easy to understand architecture for computer networks and provides an abundance of benefits to users. By having a standard architecture, developers and network engineers are able to quickly develop applications and services. Furthermore, it ensures that data is secure and reliable, and makes it easier for network engineers to quickly troubleshoot issues.
