Which protocol is identified as a simple file transfer method used over UDP?

The correct answer is Trivial File Transfer Protocol (TFTP), which is designed for simple file transfers over User Datagram Protocol (UDP). TFTP operates without the complexities of error recovery and control mechanisms found in other file transfer protocols, making it lightweight and easy to implement.

TFTP is primarily used in situations where quick and uncomplicated file transfers are necessary, such as in network booting scenarios or firmware updates for devices like routers and switches. Because it uses UDP, TFTP does not establish a dedicated connection before transferring files, allowing for faster, albeit less reliable, data transmission. This simplicity and speed make it ideal for environments where reliability can be managed through other means or where efficiency is paramount.

In contrast, the other protocols mentioned are built on Transmission Control Protocol (TCP), which ensures reliable communication by establishing connections and guaranteeing data delivery, making them more robust but also more complex and resource-intensive than TFTP.