Gateway device, a control instruction processing method and program

A gateway apparatus includes a translator connected to a first network for one or more controllers to control one or more devices, and one or more aggregators. The translator includes an acquisition unit which acquires load information concerning a load on each of the controllers, a control instruction reception unit which receives a control instruction for a device from a client via the second network, a determination unit which determines whether the instruction is an aggregation target, based on the information, a first transfer unit which transfers the instruction to the aggregator corresponding to the instruction, and a second transfer unit which receives an aggregate control instruction from the aggregator. The aggregator includes a third transfer unit which receives the instruction from the translator, an aggregation unit which aggregates the plurality of instructions into one aggregate control instruction, and a fourth transfer unit which transfers the aggregate control instruction.