Node device for ring system, and system and method for constructing multiple spanning trees by using the same node device

摘要

An object of the present invention is to provide a multiple spanning tree system in which a plurality of spanning trees are constructed in a ring system to effectively use a band of the ring system. A plurality of bridge protocol processing sections are provided in a node device to enable a plurality of bridge protocol processings to be performed in a transmission path connected to one node device. Thereby, a plurality of spanning trees can be constructed and a root bridge can be placed every each node device.