Which protocol is connection-oriented and ensures reliable data delivery?

The correct choice is based on the properties of different protocols in the context of data transmission. The Transmission Control Protocol (TCP) is recognized as a connection-oriented protocol. This means that it establishes a connection between the sender and receiver before transmitting data. One of the key features of TCP is its ability to ensure reliable data delivery. It achieves this through several mechanisms, including error detection, acknowledgment of received segments, and retransmission of lost packets. This reliability is essential for applications where data integrity and order are critical.

While other protocols mentioned have specific functions, they do not provide the same level of reliability. For instance, User Datagram Protocol (UDP) is a connectionless protocol that does not guarantee data delivery, making it suitable for applications where speed is prioritized over reliability, such as video streaming. Hypertext Transfer Protocol (HTTP) operates on top of TCP; it can leverage the reliability of TCP but is primarily an application-level protocol for transmitting web content. File Transfer Protocol (FTP), although also built on TCP, is specifically designed for file transfers and does not define its connection characteristics in the same way TCP does. Therefore, TCP stands out as the protocol that directly ensures reliable and ordered data delivery.