Which of the following protocols does NOT provide error recovery?

The protocol that does not provide error recovery is User Datagram Protocol (UDP). UDP is a connectionless protocol that sends messages, called datagrams, without establishing a connection or ensuring that the data is reliably received. It does not include built-in mechanisms for error checking or recovery, meaning that if packets are lost, duplicated, or received out of order, UDP does not attempt to correct these issues.

This characteristic makes UDP suitable for applications where speed is more critical than reliability, such as video streaming, online gaming, or voice over IP (VoIP), where the loss of a few packets may not significantly impact the overall user experience. Instead, applications that rely on UDP must implement their own form of error handling if needed.

In contrast, protocols such as TCP (Transmission Control Protocol), HTTP (Hypertext Transfer Protocol), and FTP (File Transfer Protocol) are built on top of TCP and provide mechanisms for error detection and recovery, ensuring that data transmission is reliable and complete. TCP, for instance, uses acknowledgments and retransmissions to guarantee that data is sent and received accurately.