摘要 |
<p>In a ring type network, a master node sends a measurement packet to a slave node; receives the measurement packet which has been circulated among a plurality of slave nodes; according to time-keeping of an internal clock; stores a sending time and a received time of the measurement packet; sends a measurement result notifying packet showing the sending time and the received time of the measurement packet to the slave node, and each slave node receives the measurement packet; sends the measurement packet received to the next node; according to time-keeping of the internal clock, stores a received time of the measurement packet; further receives a measurement result notifying packet; calculates a time correction value using the sending time and the received time of the measurement packet shown in the measurement result notifying packet received, the received time of the measurement packet stored, a total number of node apparatuses, and a difference between an order of the slave node and an order of the master node according to the packet transferring order, and corrects a time of the internal clock using the time correction value calculated.</p> |