4. Transport Layer

            The transport layer takes data transferred in the session layer and breaks it into “segments” on the transmitting end. The transport layer carries out flow control, sending data at a rate that matches the connection speed of the receiving device, and error control, checking if data was received incorrectly and if not, requesting it again. examples of the transport layer is TCP or the Transmission Control Protocol. It is responsible for the End to End Delivery of the complete message. Transport Layer is called as Heart of OSI model. Data in the Transport Layer is called as Segments. Transport layer transfer the data and system with the help of TCP & UDP protocol