A communications protocol that does not require the establishment of a session between two nodes before transmission can begin. For example, the transmission of frames within a local area network (LAN), such as Ethernet, Token Ring and FDDI, is connectionless. As soon as a frame has been constructed, it is inserted into the network (put on the wire).
In an IP network, the UDP transport protocol, which is used for voice over IP (VoIP) and video calling, is connectionless. Contrast with connection oriented
. See UDP