| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable a user terminal to obtain a clock synchronized with a standard clock of a master station (master clock) in a packet network, where the delay time of user packet changes, depending on the length of queue at a router or at a switch. <P>SOLUTION: In this method, transmission time t1 is loaded to an inquiry packet, and t1, reception time t2 of the inquiry packet, and transmission time t3 of a reply packet are loaded to the reply packet. On the basis of the reception time of the reply packet and t1, t2, and t3 which are obtained from the reply packet, time error between the slave clock time and the master clock time is computed. A value, corresponding to the delay time of a router where the inquiry packet passes is added to t1 and rewritten, and a value corresponding to the delay time of a router, where the reply packet passes, is added to t3 and rewritten. Using t2 and t4 and rewritten t1' and t3', the time error is computed. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
