Open Systems Interconnection (OSI)

The Open Systems Interconnection (OSI) is a standardization model developed by the International Organization for Standardization (ISO) to facilitate communication between different computer systems. It is a layered architecture that divides the communications processes into seven distinct layers. Each layer is responsible for a different aspect of communication and has its own set of protocols and standards.

The OSI model has enabled the development of cables that are designed to work with the different layers of the model. Starting from the bottom layer of the OSI model, the physical layer is concerned with the actual physical connection between two devices. This layer is responsible for providing electrical, mechanical, and procedural connections, as well as the transmission of bits over a physical medium. The cables used for this layer include coaxial cables, twisted pair cables, and fiber-optic cables.

The data link layer, which is the second layer of the OSI model, is responsible for providing the reliable transmission of data between two nodes that are connected through the physical layer. This layer is responsible for providing methods for detecting and correcting errors in data transmission. The cables used for this layer include twisted pair cables, fiber-optic cables, and Ethernet cables.

The third layer of the OSI model, the network layer, is responsible for providing the logical addressing of nodes on a network, as well as the routing of data packets. This layer is also responsible for providing congestion control and quality of service (QoS) mechanisms. The cables used for this layer include Ethernet cables and fiber-optic cables.

The fourth layer of the OSI model, the transport layer, is responsible for providing the reliable transmission of data between two nodes. This layer is responsible for providing methods for detecting and correcting errors in data transmission.