| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide technology which can switch communication paths without discarding user frames before stopping the functions of relay devices as planned. <P>SOLUTION: An operator enters a command for stopping user frames using a monitoring terminal, not shown, which is connected to a management relay point 6. At the management relay point 6, a Force Down area 66 of a received CCM frame is set to ON (1) based on the input command before the area being relayed. At management end points 1 and 2, if the Force Down area 66 of the received CCM frame is set to ON (1), user frame transmission to a redundancy path is started. At the management end points 1 and 2, furthermore, a CCM frame which has had its Traffic Field area 60 set to OFF (0) is generated, which is then transmitted toward a communication path. <P>COPYRIGHT: (C)2012,JPO&INPIT |
