What is osi model in computer network

The OSI Model, also known as OSI Model, is an Operating System Interconnection Model used for communications in computer networks. In this model, network communication is divided into 7 layers of OSI model, which are called Layers.

Each layer is responsible for performing specific tasks and supporting communication protocols. In this article, we will get detailed information about different levels of OSI Model.

What is osi model

The OSI model is a reference model for communication between two users in a network. This model has 7 layers which are not connected to each other. Each layer of the OSI model is not dependent on each other but transmission of data occurs from one layer to another.

7 Layers Of OSI Model

1). Physical Layer

Physical Layer is the lowest level of the OSI Model. This layer deals with network hardware and provides the ability to send or receive data from one machine to another without any transformation. It is made up of various elements such as Cable, Hub, Switch, Repeater, and network card. Physical Layer converts data into bits and converts the data into electronic, radio, electricity, or infrared signals etc.

2). Data Link Layer 

Data Link Layer is the second level of OSI Model and comes above the Physical Layer. The main function of this layer is to send data from one node to another in an impeccable and secure manner. This layer divides the data into frames and contains logical addresses and checks messages to deliver these frames over the network. This layer is responsible for handshaking, error detection, and error correction.

3). Network Layer 

The Network Layer is the third level of the OSI Model and is used to route data packets from one node to another. The packets received through this layer are delivered to the right node through logical addressing and routing. This layer manages the traffic of the network and organizes the sent packets according to the allocated bandwidth.

4). Transport Layer 

The Transport Layer is the fourth level of the OSI Model and is responsible for end-to-end verification and acceleration. The main objective of this layer is to transmit data from one host to the second host in a secure and systematic manner. This layer divides the data into segments, performs validation through port numbers, controls the speed of transmission of data, and corrects errors.

5). Session Layer

The Session Layer is the fifth level of the OSI Model and is responsible for establishing and handling the transport connection. This layer handles authentication and session operations between two hosts. The Session Layer establishes a logical session between transport connections, operates the session, and terminates the session. It supports the storage of tokens, synchronization points, and data for sessions.

6). Presentation Layer

The Presentation Layer is the sixth level of the OSI Model and is responsible for simplifying, encrypting, decrypting, and formatting the data. This layer translates data into machine-directed language so that one host is able to read and understand the message to another host. This layer is also responsible for compressing and decompressing the data.

7). Application Layer 

Application Layer is the seventh and final level of the OSI Model. This layer contains different protocols to operate the network’s users and user applications, such as HTTP, FTP, DNS, SMTP, and Telnet, etc. This layer is responsible for user interface, file transfer, and network operations. Users operate on the network through the application layer and are used to operate on the network.

Features Of OSI Model

The OSI Model is a comprehensive and complete networking architecture that follows universal rules to provide level-wise systematization and operation. Some of its main features are:

  • Structural type: OSI Model is structurally organized and divided into different levels. It ensures that every level performs its functions and remains organized with proper operations.
  • Protocol stack: Different protocols are used for each level in the OSI model. This ensures that the highest level of guidance can be followed for communication of data across different levels.
  • Protocol Ratio: Each level in the OSI Model has its own Protocol Ratio. This ensures that supply-demand is used for communications at different levels and data is handled correctly.
  • Independent Level Development: Each level in the OSI Model performs its functions independently and controls its own operating process. This ensures that communications at any level have no impact on any other level.
  • Protocol Testing: There is a special Protocol Testing program to test the protocols used in each level of the OSI Model. With this, the convenience and security of the protocol can be measured.

These were some of the main features that make the OSI Model a powerful and secure networking architecture. Due to such features of OSI Model, it is the most popular networking architecture nowadays.

Advantages Of OSI Model

There are many advantages due to the use of OSI Model. Here are some of the main advantages:

  • Standardized structure: The OSI Model is a standardized structure that can be used to facilitate communications between different networking devices. This ensures irreversible strategic networking that is capable of meeting the communication needs of different devices.
  • Supply-Demand Balance: Due to the level systematization in the OSI Model, users are allowed to communicate securely and effectively for the supply-demand balance. The circulation at one level has no impact on the second level, making operation and management of communications simple.
  • Development of new protocols: Due to level systematization in the OSI Model, development and adaptation of new protocols is easier. By ensuring separate innovation of protocols at each level, it is possible to develop new and progressive protocols that enable secure, faster and more adaptive communications.
  • More Security: Security is an important part in the OSI Model. Implementing security measures at every level helps in making the networking architecture secure. Additionally, the protocols and structure of the OSI model help identify and control security risks.

Because of these advantages of the OSI model, it is a widely used networking architecture that enables secure, standardized, and reliable communications.

Disadvantages Of OSI Model

OSI (Open Systems Interconnection) Model has some disadvantages which are as follows:

  • Complexity: The OSI model can be quite complex, making it difficult to understand and provide. Since it has 7 levels, each level requires different protocols, which can be inseparable and different.
  • Worth: Because each level of the OSI model requires different protocols, the cost of compliance can be high. Therefore, it may be difficult for some organizations or network engineers to adopt.
  • Organizational Conflict: Another disadvantage of the OSI Model is that it may conflict with business protocols. This may delay the development and standardization of a particular protocol, which may impact interoperability and highest security.
  • Utility Of More Levels: Since there are 7 levels in the OSI Model, its usefulness may be excessive for some small networks and users. Therefore, using it in a commercial project may be extremely inappropriate and extremely difficult.

These are some of the disadvantages of OSI Model that should be kept in mind during their use.


OSI Model In Hindi is an important standardization model that helps in ensuring network structure and operation. Its benefits include standardization, structural segmentation, cross-platform support, commercial marketing support, and organizational management.

However, its disadvantages include complexity, cost, internal storage, latency of communications and slow performance. If this model is implemented correctly, it can provide a reliable and secure network structure.


What is OSI Model?

The OSI Model is a structural model designed to understand and operate computer networks. This model divides communications protocols into seven different levels, where each level performs specialized functions and most levels use the services of the upper level.

How many layers are there in a computer?

There are seven layers in a computer network which distinguish seven levels of the OSI Model.

Which layer is not in OSI Model?

In the OSI Model, none of the above seven layers is the same as the layer called “Application”.

What are the 7 layers of OSI Model?

-Physical Layer
-Data link layer
-Network layer
-Transport layer
-Session layer
-Presentation layer
-Application layer

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