A service mode in which a packet-switched network routes each datagram without regard to any other datagrams that might have preceded it or that might follow it. Datagram service is connectionless, meaning that there is no need to set up a predetermined path for the packets to travel through the network. Rather, each packet in a stream of datagrams can take an entirely different route from originating host to destination host.As a result, the datagrams can arrive at the destination host out of sequence. Note: In the wild, the routing protocol commonly determines the path in advance, anyway. See also connectionless, datagram, packet, and packet switch.