What Transmission Control Protocol/Internet Protocol transport layer protocol provides reliable data delivery services?

The Transmission Control Protocol, often abbreviated as TCP, is known for its reliable data delivery services at the transport layer of the Internet Protocol Suite. It establishes a connection-oriented communication channel between two endpoints, ensuring that data packets are delivered in the correct order, without duplication, and without loss. TCP accomplishes this through mechanisms like error checking, acknowledgment of receipt, and retransmission of lost packets, which helps maintain the integrity of the data as it travels across networks.

In contrast, the Internet Protocol focuses primarily on addressing and routing packets of data across networks, but it does not inherently provide reliability or guarantee delivery. User Datagram Protocol (UDP) offers a simpler, connectionless data transmission service without the overhead of reliability features that TCP provides, making it faster but less reliable. The Internet Control Message Protocol (ICMP) is used for sending error messages and operational information rather than for general data transmission. Therefore, TCP stands out for its reliable services, making it the correct choice for this question.