switch
termnetworking
A device that forwards frames within a network by learning which addresses live on which port.
It learns by watching: every frame that arrives teaches it where the sender is, and anything it has not learned yet is flooded to every port. That single behaviour explains most of what operators see - a network that works before the table populates, traffic appearing where it should not during a topology change, and the reason a loop is catastrophic rather than merely wasteful, since flooded frames multiply with nothing to stop them.
Also known as: layer 2 switch