| 摘要 |
PURPOSE:To increase the transmission efficiency, by transmitting test data to both duplicated system loop transmission lines with a fixed time interval, estimating the traffic with a time difference circulated with this test data, and selectively using the transmission line less in the traffic. CONSTITUTION:When transmission controllers 11-13, 21-23 perform reception only, a switch 61 is changed over to (a) side and in case of store-and-fo-ward mode, and switch 61 is changed over to (b) or (c) side. If transmission data are abundant (traffice is abundant) since each transmission controller is at store-and- forward mode, transmission delay is caused. Thus, each transmission controller transmits a test signal to both transmission lines 1, 2 prior to the transmission in advance and the time of circulation is tested, and when data is transmitted, shorter time of circulation is selected and used to make the traffic uniform. |
