In networks, round robin allows each node on the network to use the communication
medium. If the node has data to send, it’s given a certain amount of time to complete
the transmission, at the end of which, the opportunity is passed to the next node. If
the node has no data to send, or if it completes transmission before the time is up, then
the next node begins its turn. Round robin is an efficient technique when there are
many nodes transmitting over long periods of time. However, when there are few
nodes transmitting over long periods of time, the overhead incurred in passing turns
from node to node can be substantial, making other techniques preferable depending
on whether transmissions are short and intermittent, as in interactive terminal-host
sessions, or lengthy and continuous, as in massive file transfer sessions.