Which protocol is responsible for providing a reliable transmission of data over networks?

The Transmission Control Protocol (TCP) is responsible for providing a reliable transmission of data over networks. TCP operates at the transport layer of the OSI model and is designed to ensure that data is sent and received without errors. It accomplishes this through several key features, such as segmentation, error checking, and retransmission of lost packets.

When data is transmitted using TCP, it is divided into segments, each of which is numbered. This numbering allows the receiving device to reassemble the segments in the correct order. Additionally, TCP uses a method called acknowledgment (ACK), where the receiver sends back an acknowledgment for segments received correctly. If a segment is lost or corrupted during transmission, TCP identifies this and retransmits the affected segment, ensuring data integrity.

Due to these mechanisms, TCP is considered a connection-oriented protocol, as a dedicated connection is established between sender and receiver for the duration of the session, providing a reliable and orderly communication channel. This makes TCP suitable for applications where data delivery must be guaranteed, such as web browsing, email, and file transfers.