Network equipment, network systems, network methods, and network programs

摘要

A network device (100) is included in a ring type of network system (500) for selecting a time master. A link processing unit (20) generates a link for communicating a frame. The link processing unit (20) has a frame discarding function for discarding a frame so as to avoid a broadcast storm. A path control unit (108) generates a time delivery path starting from and terminating at a time master for each of clockwise and counterclockwise routes from the time master. The path control unit (108) communicates a time synchronization message, which is one of frames, to be used for time synchronization of a plurality of network devices (100). Upon acquisition of the time synchronization message, a filtering unit (103) passes therethrough the time synchronization message irrespectively of the frame discarding function.