NETWORK SYSTEM AND DATA TRANSFER DEVICE

摘要

When a multicast DA is used for an OAM frame, increases of the network bandwidth load and the node processing load and degradation of the network reliability caused as a result that a frame is sent out through all the paths in a broadcast domain are prevented. A MAC address and other basic frame information and the MEGID are associated with one another, MEGID information is added to the OAM frame, and they are sent out from an edge node serving as an end point of an ME. A relay node of the ME has a path control table used for OAM frame control. A filter is generated by means of snooping of the OAM frame. When the relay node support no OAM function, the MEGID is represented by a VLAN tag, and path control is made by means of the conventional snooping function according to the VLAN tag.