Transport Layer

The transport layer is the fourth layer in the OSI model and is responsible for ensuring that data is transmitted reliably and efficiently across a network. This layer provides services such as error detection, flow control, and data segmentation. The two most commonly used transport layer protocols are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

TCP is a connection-oriented protocol that provides reliable, ordered, and error-checked delivery of data between applications. It establishes a connection between two devices before transmitting data and ensures that the data arrives at its destination in the same order it was sent. TCP also performs flow control, which manages the rate at which data is sent to avoid overwhelming the recipient.

UDP, on the other hand, is a connectionless protocol that does not provide reliability or flow control. Instead, it focuses on speed and efficiency. UDP is often used in applications such as online gaming and video streaming, where speed is more important than accuracy. While UDP may result in lost or out-of-order data, it can also lead to faster data transfer speeds since there is no need to establish a connection before transmitting data.