| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress switching delay to a minimum and to suppress useless switching in redundant switching for making a priority determination by comparing the number of effective ports under control of a redundant device in a network system where devices are made redundant and constituent devices thereof. <P>SOLUTION: A network repeater which implements a redundant switching function uses a search frame or an information exchange frame to grasp a port connection state of a network system beforehand. When a failure occurs, regarding ports connected to a port where the failure occurs via devices under control, the state is confirmed positively to grasp the portion where the failure occurs and determine the necessity of switching. Thus, useless switching such as cut-back just after switching is prevented and since a mechanism for waiting for a fixed time is not required, high-speed switching can also be performed. <P>COPYRIGHT: (C)2013,JPO&INPIT |
