JPH05300164

PURPOSE:To previously avoid the erroneous recognition of link error by surely judging original error, which is mixed into a line symbol for observing an original line state, and error generated in the line identification disable state (not error) of previously decided time to be generated when changing the line symbol. CONSTITUTION:Concerning this FDDI link error monitor system, each station connected on the FDDI network is provided with a link error detection state machine 2 to judge a line status for disabling line identification when the line status for disabling line identification inputted from an opposite side station through a line is received continuously for time decided in advance, and to judge an error signal at the time of receiving the line status for disabling line identification when the line status for disabling line identification is finished within the time decided in advance.