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OSI Model Full form

: Read this article to know about OSI full form, its history, characteristics, advantages and disadvantages.

The International Organisation for Standardisation (IOS) developed the open systems interconnection (OSI) model, a conceptual framework that enables various communication systems to exchange data via agreed-upon protocols. The OSI, or Open Systems Interconnection, offers a standard for various computer systems to be able to interact with one another.

Table of Contents

  1. History of OSI Model
  2. Seven Layers Of The OSI Model
  3. Characteristics:
  4. Advantages:
  5.  Disadvantages: :

History of OSI Model

Technology experts started looking for the best ways for computer systems to interact with one another in the 1970s. In the following years, several rival models were developed and released to the public. However, it wasn’t until 1984 that the International Organisation for Standardisation (ISO) proposed OSI as a method to finally develop a framework that software companies worldwide could use as the foundation of their communication systems. OSI was created using the best parts of different competitive networking reference models.

Seven Layers Of The OSI Model

The OSI Model has seven layers. Each layer has a particular purpose. 

  • Physical Layer

The physical layer is in charge of the wired and wireless connections that physically connect network components. it is also in control of bit rate regulation and the conveyance of raw data, which is just a stream of 0s and 1s.

  • Data-Link Layer 

Directly linked nodes are used for node-to-node data transfer at the data link layer, where data is collected into frames. The data link layer itself has two sublayers, named LLC and MAC. 

  • Network Layer

The network layer takes frames from the below layer and sends them to the correct locations. The network layer locates the endpoint (internet protocol) using IP addresses.

  • Transport Layer

The transport layer provides data flow restrictions and loophole-checking techniques, which also check data movement across a network. It chooses how much data should be transferred, where it should go, and its speed.

  • Session Layer

The session layer controls the communication between many computers. It also creates a machine-to-machine connection or link, managed, and terminated. The session layer services also include identification and synchronisations.

  • Presentation Layer

Depending on the syntax, the presentation layer generates data packs for the application layer. For this, it is called the syntactic layer.

  • Application Layer

At this layer, both the application layer and the user have immediate access to the software programme. This layer provides network services to end-user programmes, including Office 365 and web browsers. The application layer controls connection, synchronisation and resource availability.

Characteristics

  • Upper layers and lower layers make up the OSI Model’s two layers
  • The top layer handles software application problems
  • Hardware and software-based data transfer are handled at the lowest layer
  • The physical layer deals with data held on physical media

Advantages

  • It is regarded as a typical paradigm for computer networkin
  • The OSI model accommodates both connection-oriented and connectionless services
  • It is adaptable to many different protocols
  • The approach is more flexible and safe than bundling all services into one layer

Disadvantages

  • The presentation layer, which handles user intervention, and the session layer, which is responsible for session management, are less valuable than other OSI model levels
  • Layers cannot operate concurrently; instead, they must each wait for data from the layer before them