Which protocol is considered connectionless?

The correct choice is based on the characteristics of connection-oriented versus connectionless protocols. The User Datagram Protocol (UDP) is classified as a connectionless protocol because it does not establish a connection before sending data and does not guarantee the delivery of packets. This means that UDP provides a method for sending data without the overhead of ensuring that the data reaches its destination reliably, allowing for faster transmission suitable for applications where speed is preferred over reliability, such as video streaming or online gaming.

In contrast, the Transmission Control Protocol (TCP) is connection-oriented, meaning it establishes a connection through a handshake process before transferring data and guarantees delivery, maintaining the order of packets. The Internet Control Message Protocol (ICMP) primarily serves to send messages about the network status and errors rather than transferring user data. Although Address Resolution Protocol (ARP) facilitates mapping IP addresses to MAC addresses, it operates in a manner that does not involve establishing a connection, but it still functions effectively in a different context primarily focused on address resolution.

Therefore, UDP’s design emphasizes speed and simplicity without the need for establishing connections or ensuring data integrity, making it the proper example of a connectionless protocol.