METHOD FOR MEASURING FRAME LOSS, SYSTEM FOR MEASURING FRAME LOSS, AND DEVICE FOR MEASURING FRAME LOSS

摘要

A frame loss measurement system accurately calculating frame loses without inviting greater complexity, larger size, or slower processing speed. The number of data frames transmitted between one apparatus (32) and the other apparatus (34) is counted by a transmission counter (14), while the number of received frames is counted by a reception counter (24). When an LMM frame (36), LMR frame (38), CCM frame, or other OAM frame for frame loss measurement is transmitted, the value of the transmission counter (14) is cached in a transmission counter value cache memory (18). At the time of generation of an OAM frame at an OAM frame generation unit (16), the value of the cache memory (18) is used so as to generate an OAM frame carrying the value of the transmission counter at the time of transmission of the OAM frame transmitted previously. The frame loss is calculated from the difference of the value of the transmission counter carried in the OAM frame from the previous value and the difference of the value of the reception counter at the time of reception of the previous previous OAM frame from the previous value.