A network system includes: a first master device configured to carry out, in every cycle, (i) a process of receiving data from a first slave device, (ii) a process of carrying out, in accordance with pre-allocation, a part of a first process with respect to the data, (iii) a process of transmitting data corresponding to a remainder of the first process to an outside entity in accordance with the pre-allocation and receiving a result corresponding the remainder of the first process, and (iv) a process of transmitting, to the first slave device, a result corresponding to the first process; and at least one second master device configured to transmit, to the first master device before a period allocated to the first process within the cycle ends, the result corresponding to the remainder of the first process with respect to the data received from the first master device.