Management device, system, and method

A management system, comprising:

• a management device;
• and
• master devices, wherein
• the management device includes:
• a memory;
• and
• one or more processors configured to function as a first calculator, first notifier, and a first acquirer, wherein
• the first calculator calculates a time offset for each of the master devices each performing, when a measured time reaches a certain time, time synchronization with a slave device, which is a management target, at the measured time;
• the first notifier notifies each of the master devices of offset information indicating the time offset;
• and
• the first acquirer acquires, for each of the master devices, the synchronization information, the synchronization information including period information that indicates a synchronization period in which the time synchronization is performed, wherein
• the first calculator calculates, for each of the master devices, the time offset in accordance with the following expression:
• time offset=(synchronization period/number of pieces of acquired synchronization information)×a natural number that is unique to each of the master devices and smaller than the number of pieces of acquired synchronization information, and
• each of the master devices includes:
• a memory;
• and
• one or more processors configured to function as a second acquirer, a first time measurer, synchronizer, and a second notifier, wherein
• the second acquirer acquires the offset information;
• the first time measurer measures a time and changes the measured time to a time obtained by offsetting the measured time with the time offset indicated by the offset information;
• the synchronizer performs the time synchronization with the slave device at the changed measured time when the changed measured time reaches the certain time;
• and
• the second notifier notifies the management device of synchronization information on the time synchronization, whereby
• the management device sets time offsets differing from one another to the master devices so that measured times are shifted from one another to avoid an occurrence of confliction due to the time synchronization.

A management method, comprising:

• calculating a time offset for each of master devices performing, when a measured time reaches a certain time, time synchronization with a slave device, which is a management target, at the measured time;
• and
• notifying each of the master devices of a change notification causing each of the master devices to change the measured time of each of the master devices to a time obtained by offsetting the measured time with the time offset, wherein
• the management method further comprises:
• acquiring, for each master device, synchronization information on time synchronization, the synchronization information including period information that indicates a synchronization period in which the time synchronization is performed, and
• the calculating includes calculating, for each of the master devices, the time offset in accordance with the following expression:
• time offset=(synchronization period/number of pieces of acquired synchronization information)×a natural number that is unique to each of the master devices and smaller than the number of pieces of acquired synchronization information, whereby
• the management method sets time offsets differing from one another to the master devices so that measured times are shifted from one another to avoid an occurrence of confliction due to the time synchronization.