When the states of a large number of objects must be transferred to another device, the overhead can be greatly reduced and the object states can be synchronized in a short period of time. At the time of creating an object, an object creation function arranges the internal state of the object into a byte sequence in a region for transfer, and sets mapping data in a mapping management table. When an application program has manipulated the internal state by using an accessor method, the state is set in the byte sequence in the region for transfer, or obtained therefrom. A transfer function transfers the byte sequence in the region for transfer and the mapping management table to a receiver, where a reproduction function reproduces the object based on the received data.