Learn the different aspects of the OSI model
Also known as the Open Systems Interconnection Reference Model, the OSI model was created as one of the features of the Open Systems Interconnection initiative, which segregates a computing network into multiple layers, including presentation, transport, physical layers and data. The layers of this model provide important services, such as error-free communications, access to subnets, and data transport. To use this model effectively and easily, it is important to have sufficient background on the functions and design of each OSI layer.
The history of the OSI model
The initiative for the development of the OSI framework architecture began in 1978 by the International Organization for Standardization (ISO). It consists of two elements, namely a protocol group and the basic reference model. The inclusion of protocols is important for the interaction of entities on two different hosts. The concept behind the development of the architecture was inspired by the work of Honeywell computer scientist Charles Bachman. However, over time, the design of the OSI model layers has evolved from experience associated with various network models, such as the CYCLADES network. The design used by computer experts today was presented in ISO 7498.
The different layers of the OSI model
The OSI model used by computer scientists today consists of seven layers, which are important for the efficient and proper implementation of software and hardware. Each layer of the framework is essential to the functionality of the other layers. The first four layers of the model are called the physical layer, data link layer, network layer, and transport layer. The remaining layers are known as the Session Layer, Presentation Layer, and Application Layer. The basic functions of this framework include the transfer of data streams, error control, flow control, as well as segmentation and de-segmentation. Apart from these purposes, the layers are also important to control unauthorized interactions between the devices that are connected in a particular computer network. In addition, they are essential to determine the availability of resources and the identification of communication partners.
Additional information and other important details
The OSI model features various protocol standards that are developed and used by different organizations, such as the American National Standards Institute (ANSI), the Institute of Electrical and Electronics Engineers (IEEE), and the International Telecommunication Union (ITU). The layered approach used for the development of this model has several advantages, including modular engineering, improved teaching and learning, accelerated progress, and reduced complexity.