For transmitting predetermined information to a second communication station via a first communication station, the second communication station receives the predetermined information via one first communication station from among a plurality of the first communication stations. Upon transfer of a function of transferring the predetermined information to the second communication station to another first communication station, the another first communication station receives the predetermined information from the one first communication station, and transfers the same to the second communication station, with attaching distinction information to the predetermined information for distinguishing between the predetermined information transferred to the second communication station via the another first communication station and the predetermined information received from the another first communication station directly.