UDP

User Datagram Protocol (UDP) is a connectionless protocol that can be used to address data to a single network participant by sending to the participant's IP address directly, or it can distribute data to an entire network by sending the data to a network broadcast address. UDP does not recognize lost packets, but it is faster as it does not maintain a session.

UDP is typically used for applications that rely on throughput, such as live video/audio streaming; here, when a packet gets lost does not matter. UDP broadcasts are typically used by applications in which the location of the "other side" has yet to be discovered. Typical examples of such applications are a DHCP client searching for a DHCP server, or a client trying to discover one or more devices with yet unknown addresses in a network.