| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a duplex switching system which automatically switches a communication path to a path of a standby system to prevent interruption of data communication in the system even when communication interruption between a control terminal and a device such as a line controller occurs. <P>SOLUTION: A system control terminal 11 of an active system constantly performs state monitoring of a line controller 13 of the active system by a fixed cycle, when a communication path 17 becomes in a communication impossible state, issues an operation system switching instruction to a line controller 14 of the standby system via a communication path 18. The line controller 14 of the standby system which receives the operation system switching instruction switches the self-device from the standby system to the active system and simultaneously issues the operation system switching instruction to a line controller 13 of the active system via a communication path 21. The line controller 13 of the active system which receives the operation system switching instruction switches the self-device to the standby system. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
