A METHOD FOR PRIMARY AND BACKUP LINKS PROTECTION IN PASSIVE OPTICAL NETWORK AND A RING-BASED SYSTEM

摘要

A PON ring system and a method for realizing primary and backup link protection in a passive optical network (PON) are provided. The method includes the following steps. A PON ring is established between at least two optical line terminations (OLTs) through at least two user side edge nodes or network side edge nodes. Each of the OLTs is coupled to any other OLT through the at least two edge nodes. Two links respectively in a clockwise direction and a counterclockwise direction exist in the PON ring, in which one link is a primary link and the other is a backup link. When the primary link is normal, any node in the PON ring receives data via the primary link, and when the primary link fails, the failure is notified to nodes in the PON ring, so that any node in the PON ring receives data via the backup link. Therefore, the present invention reduces the impact on the PON caused by single link failure in the network.