Network and node device

摘要

A switching system (B1-B4) for connecting and disconnecting a link between nodes (A-E), so that when a network has a redundant link which forms a loop among nodes - this loop preventing normal connection relationship being maintained - the connection relationship can be made normal by controlling this switching means. Controlling the switch system also achieves rapid recovery from a fault which has occurred in a link between nodes, by utilizing the aforementioned loop to form a route that bypasses the fault.