Abstract: An apparatus and method for fault isolation and bypass in a dual ring communication system provides a reconfiguration unit capable of attachment to a dual ring communication system having a plurality of reconfiguration units. The disclosed reconfiguration unit has a single adapter to the dual ring communication system and includes isolation and wrap switches capable of isolation and bypass of faults. A reconfiguration unit having a single adapter to the dual ring communication system detects failures on the ring and generates a failure frame which if not received from the ring causes the reconfiguration unit to enter a downstream wrap state. The reconfiguration unit enters an upstream wrap state if a failure frame is received from the nearest downstream reconfiguration unit.

Abstract: Methods and systems for determining the address of the nearest downstream reconfiguration unit in a dual ring communication system. In a dual ring communication system having a plurality of reconfiguration units one of the reconfiguration units determines if a Reconfiguration Unit Monitor is active on the system. If a Reconfiguration Unit Monitor is not active the reconfiguration unit requests and stores address information from the remaining reconfiguration units in the ring and assembles a ring sequence reconfiguration unit ring map. The reconfiguration unit transmits the reconfiguration unit ring map to the remaining reconfiguration units in the ring. Reconfiguration units receive the reconfiguration unit ring map from the Reconfiguration Unit Monitor and extracts the address of the nearest downstream reconfiguration unit from the reconfiguration unit ring map.