What is the main function of the TCP protocol in networking?

The main function of the TCP (Transmission Control Protocol) is to ensure reliable transmission of data across a network. It does this by breaking files into smaller packets and managing their reassembly at the destination. This segmentation allows networks to effectively transmit large amounts of data without overwhelming the network's capacity or losing information during transmission.

TCP not only segments the data into manageable packets but also establishes a connection between sender and receiver to ensure that all packets are sent and received in the correct order. It uses mechanisms such as sequence numbers and acknowledgments to confirm the successful delivery of packets, and it can retransmit any lost packets. This reliability makes TCP an essential protocol in applications where data integrity and order are crucial, such as web browsing, email, and file transfers.

The other functions mentioned are not the primary roles of TCP. While managing network addresses relates more to the Internet Protocol (IP), handling real-time data streaming typically falls under protocols such as UDP (User Datagram Protocol) which prioritizes speed over reliability. Similarly, data encryption is handled by different protocols and layers within networking, such as SSL/TLS, rather than by TCP itself.