Patent ID: 9418096
Filing Date: 2016-08-16
CPC Classification: G06F

Claim Text:
1. A control method executed by a system including a plurality of computers, the plurality of computers including a first computer, a plurality of second computers coupled to the first computer, and a third computer coupled to the plurality of second computers, the plurality of computers respectively storing a replication of data, the plurality of second computers arranged on a plurality of routes between the first computer and the third computer, the control method comprising: transmitting, by the first computer, an update request to the plurality of routes, when the update request is received from a first client device; generating, by the third computer, updated data by updating the replication of data stored in the third computer and transmitting an updated request to the plurality of routes, when the update request is received from all of the plurality of routes; generating, by the plurality of second computers, the updated data by updating the replication of data stored in the plurality of second computers, when the updated request is received from the third computer; receiving, by a target computer of the plurality of second computers which is arranged on a first route among the plurality of routes, a read request of the data from a second client device; selecting one of the plurality of second computers which is arranged on a second route different from the first route among the plurality of routes, as a query destination; transmitting a verify request to inquire whether the update request has been received, to the query destination; transmitting the updated data to the second client device when the query destination has received the update request; and transmitting the data before the updating to the second client device when the query destination has not received the update request.