A member-store functional unit transfers the name of a member store and the title of a campaign to an ID-assigning functional unit which assigns IDs to the title of the campaign and the name of the member store. The ID-assigning functional unit then transmits the IDs to an encoding functional unit. A broadcasting functional unit broadcasts the IDs, encoded by the encoding functional unit, by multiplexing the IDs in an audio signal. A reception functional unit receives the IDs whereas a decoding functional unit extracts and decodes the IDs. The decoding functional unit then outputs the IDs to a customer-number-assigning functional unit with a receiver ID. The customer-number-assigning functional unit forms a judgment on validity of the member-store ID, the campaign ID and the receiver ID, and assigns a customer number to the receiver ID if the member-store ID, the campaign ID and the receiver ID are found valid. An anonymous-customer management functional unit sends the customer number to a member-store functional unit so as to make a request for a transmission of a service identified by the campaign ID to the reception functional unit by way of an anonymous-service management functional unit.