RING CONSTITUTION SYSTEM IN DUAL RING TYPE NETWORK

摘要

PURPOSE:To reduce communication control nodes which lose a communication function even when trouble occurs to a sub-ring as much as possible by allowing a communication node to send back an input signal from a ring in some direction to a ring in another direction. CONSTITUTION:A network consists of an L1 and L2 two-way main ring M which includes a monitor node SN and plural junction boxes J and the L3 and L4 two-way sub-ring S which includes plural communication control nodes I connected to said junction box J. The junction box J is provided with a switch JSW so that the sub-ring in either direction can be connected to the main ring M in either direction and the sub-ring can be by-passed. Each communication control node I is provided with a switch means SW so that a signal from the ring in some direction is sent back and connected to the ring in the other ring.