What is the primary purpose of a Transport Layer protocol?

The primary purpose of a Transport Layer protocol is to transmit messages from process to process. This layer is crucial in the context of network communication as it ensures that data is sent and received accurately between applications running on different devices across a network. By providing process-to-process communication, the Transport Layer facilitates the delivery of messages regardless of the underlying network infrastructure and can manage session states, error recovery, and data flow control.

This focus on end-to-end communication means that the Transport Layer protocols, such as TCP (Transmission Control Protocol) and UDP (User Datagram Protocol), handle tasks like segmentation of data, reassembly at the destination, and maintaining the correct sequencing of packets, ensuring that users receive complete and correctly ordered messages.