Which protocols operate at the Transport Layer?

The Transport Layer is a crucial part of the OSI (Open Systems Interconnection) model, primarily responsible for end-to-end communication, ensuring that data is transferred reliably and in the proper sequence. TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) are key protocols that operate at this layer.

TCP is a connection-oriented protocol, meaning it establishes a connection before data is sent and ensures that the data arrives successfully and in the correct order through mechanisms like acknowledgments and retransmissions. This makes it ideal for applications where data integrity is critical, such as file transfers and web browsing.

On the other hand, UDP is a connectionless protocol that allows for faster data transmission at the cost of reliability. It does not establish a connection or ensure that packets arrive in order or even at all. This makes it suitable for applications like online gaming or live streaming, where speed is more important than ensuring every packet is received correctly.

Both TCP and UDP handle the segmentation of data into packets for transmission and the management of those packets as they travel across the network, which is why they are categorized under the Transport Layer.