Which protocol is characterized as connectionless?

The correct answer is UDP, which stands for User Datagram Protocol. UDP is classified as a connectionless protocol because it does not establish a dedicated end-to-end connection before transmitting data. This lack of connection means that there is no need for a handshake process to establish a session, enabling faster data transmission.

In a connectionless environment like UDP, each packet of data (called a datagram) is sent independently, and there is no guarantee of delivery, order, or error-checking. This makes UDP suitable for applications where speed is critical, and occasional data loss is tolerable, such as in live audio or video streaming, where receiving updated data promptly is more important than ensuring every single packet arrives.

Other protocols mentioned, such as TCP (Transmission Control Protocol) and FTP (File Transfer Protocol), are connection-oriented, requiring a connection to be established before any data can be sent. These protocols focus on reliability and data integrity, ensuring that packets are delivered in order and without errors. ICMP (Internet Control Message Protocol) is primarily used for network diagnostics and doesn’t fall into the same category as UDP concerning general data transmission, as it is often embedded within other protocols rather than being a direct transport layer for user data.