RING-TYPE NETWORK AND FAIRNESS EXECUTION PROGRAM FOR RING-TYPE NETWORK

摘要

To obtain ring-type network that is capable of sensing a change in the structure of a lower layer network when there is a change, and to obtain a fairness execution program for the ring-type network, which can implement the fairness function in a fine manner even in such case. Each of RPR devices of an RPR network includes a timer, and transmits a periodic transmission request of an LRTT control frame to an LRTT control frame transmitter via an arbitrating part so that the transmitter sends the LRTT control frame to each RPR device regularly. An LRTT control frame receiver receives the returned LRTT control frame, and a round trip propagation time calculator calculates round trip propagation time from a difference between the transmitted time and the received time, and gives the result to a fairness execution part. Thereby, a fine operation of the fairness function is secured.