What is the primary function of the Transport Layer in the OSI model?

The primary function of the Transport Layer in the OSI model is to ensure end-to-end communication. This layer is responsible for providing reliable data transfer services between two hosts, managing the flow of data, and ensuring that packets are delivered correctly and in the right order. It handles error detection and recovery, making it crucial for applications that require high levels of reliability, such as file transfers or streaming media.

By establishing connections and maintaining communication sessions, the Transport Layer plays a vital role in ensuring that data moves efficiently between devices over the network. This includes segmenting larger messages into smaller packets for transmission and then reassembling them at the destination, which is essential for data integrity and proper communication.

The function of the Transport Layer contrasts with other layers. For instance, routing data packets through the network is primarily a responsibility of the Network Layer, and formatting data for presentation falls under the Presentation Layer, which focuses on data translation and encryption. Similarly, session management and flow control are handled at the Session Layer, not the Transport Layer, which focuses specifically on reliable communication between endpoints.